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Course Guide
Introduction
Welcome to OAN3161 Pharmacology & Nutrition!. This subject is comprised of Pharmacology and Nutrition. The basic concepts of pharmacology, its principles in administration, ordinances on dangerous drugs, as well as, different drug classifications are discussed. Nutrition topics comprised of nutritional assessment, balanced diet, as well as, other diets needed by clients with specific conditions. Self instructional materials will be available to facilitate your self directed learning. You will be required to draw upon your experience and reflect on your practice.
In this course guide, I will share the course learning outcomes, the overview of the plan of the course and the assessments. I will also share the expectations of being a student in this course. It is our intent to make this learning experience both convenient and fun while achieving the intended outcomes.
Course Learning Outcomes
A course learning outcome (CLO) is the expectation of what you should be able to do by the end of the course. It provides a guide to both the educator as well as the student to focus on achieving the intended outcomes. For this course, we have three course learning outcomes (CLO) that can be categorised into three domains; cognitive, psychomotor and affective. The CLOs are as follows:
CLO1 Explain the major classifications and the corresponding nursing responsibilities in relation to the pharmacological principles. (C2, PLO1). CLO2 Demonstrate the ability to reflect upon nursing practice for awareness and improvement. (A3, PLO9) CLO3 Apply the core elements of nutrients, the concept of a balanced diet and the various therapeutic diets when assessing and implementing nursing interventions. (C3, PLO2). Overview of the Teaching and Learning Plan
As an online course, we will use the Learning Management System (LMS) for all our communication, materials and assessments. We will have synchronous meeting via the LMS as well as Self Instructional Materials (SIM) to facilitate your learning and progress through the course. As an ODL learner, you are expected to be self directed. The SIM will provide you with a complete guide of the course materials and resources. Each topic will have topic learning outcomes followed by the lesson notes. Links to videos and other resources will be provided to support your learning process. You will also be given reading materials out of the SIM. At the end of each topic, there will be self check questions. Here you can test yourself. Review the notes and resources should you need to. We will also have scheduled online meetings. Here we will have discussions and tutorials. In this course procedures will be recorded and shared in the SIM. You will be required to watch and reflect on your own practice. Eight two-hour synchronous online sessions will be conducted to enhance your understanding and achievement of the learning outcomes.
ASSESSMENT
The assessments are planned as for a coursework as well as Final examination. The breakdown of the weightage is as follows:
A. Continuous Assessment Weightage %Test I 10% Test II 10% Reflective Essay 20%
B. Summative Assessment
Total 100%Final Examination 60%
TEST
A test will be given at a set time within the semester to test your knowledge of the content covered as well as your ability to apply the knowledge into scenarios. Test 1 will be given after week 3 and Test 2 within week 6.
ASSIGNMENT
You need to write a reflective essay about 1000 words.
FINAL EXAMINATION
For the summative assessment, a final examination will be given in a form of multiple-choice questions and short essay questions. It is to test your knowledge of the content covered as well as your ability to apply the knowledge into scenarios. The exam will be given online based on the exam schedule.Your Responsibility as an ODL Student
The concept of ODL is to be flexible and facilitate learning even while working. As an ODL student, you are expected to be self directed. Utilize the SIM provided and make full use of the resources (recorded lectures, videos, readings) provided. Attend synchronous meetings to facilitate discussion, clarification and guidance. You are expected to attend at least 85% of synchronous meeting. Should you miss the meeting, do refer to the recordings that will be uploaded after the meeting.
Academic Honesty
Cheating, in any form, is a very serious offence which could lead to severe disciplinary action. Cheating includes:
- using unauthorised materials in tests and examinations;
- letting another person take tests or examinations on one’s behalf OR taking tests or examinations on another person’s behalf;
- working jointly, copying or sharing another student’s work and presenting it as one’s own piece of work;
- inventing, copying or altering data, quotations or references;
- plagiarising, i.e. taking or using another person’s work without attributing the source and thus, giving the impression that it is one’s own work.
Any student caught and found guilty in the disciplinary hearing will be deemed to have FAILED in the subject and will be required to REPEAT the said subject. Any repeated offence may result in EXPULSION FROM THE UNIVERSITY
Closing Note
We are glad to have you with us
. Let's look forward to a fun, challenging and fruitful semester. Do contact me should you need any help. I will be gladly assist you.
Siti Noor Laila Binti Isa
siti.n@nilai.edu.myTopic 1: Basic Concepts of Pharmacology
LEARNING OUTCOMES
By the end of the topic, students will be able to;
1. Define the common terminology used in Pharmacology.
2. Explain the principles and three phases of drug action.
3. Explain the legal aspect of drug administration and its implications in nursing practice.
1.1 The terms below are commonly used in Pharmacology:
Pharmacotherapeutics: Study of how drugs may be best used in the treatment of illnesses – most or least appropriate to use for specific disease
Pharmacokinetics: The study of drug distribution rates between various body compartments: absorption, distribution, metabolism and excretion
Pharmacodynamics: The study of biochemical and physiologic effects of drugs; drugs mechanism of action
Pharmacognosy: The study of drugs that are obtained from natural plant and animal sources
Pharmacogenetics: Study of how each individual will respond to specific drugs
Toxicology: The study of poisons. Deals with the effects of drugs and chemicals in living systems, their detection and the treatment to counteract their poisonous effects
Drug: Any chemical that affects the physiologic processes of a living organism
Prescription: A written direction or order by a doctor for dispensing and administering drugs
Dosage: The amount of drug given for a desired effect
Minimum Dose: smallest amount of a drug that will produce therapeutic effect
Maximum dose: Largest amount of a drug that will produce a desired effect without producing toxicity
Loading dose: Initial high dose (often max) used to quickly elevate the level of drug in the blood (often followed by a series of lower maintenance doses)
Maintenance dose: Dose required to keep the drug blood level at a steady state in order to maintain the desired effect
Toxic dose: amount of a drug that will produce symptoms of poisoning
Lethal dose: Dose that causes death
Efficacy/ effectiveness/ action of drug: The ability to cause the expected or intended effect of a drug in the treatment of disease
Potency: Strength of a medicine ~ It is a measure of how much a drug is required in order to produce a particular effect
Interaction: When one drug modifies the action of another drug interaction occurs
Indications: a list of medical conditions or diseases for which the drug is meant to be used
Actions: a description of the cellular changes that occur as a result of the drug.
Contraindication: a list of conditions for which the drug should not be given
Warnings and cautions: a list of conditions or types of patients that require closer observation for specific side effects when given the drugs
Adverse drug reaction (ADR): Any unexpected, unintended, undesired or excessive response to a medication. May or may not be preventable. May or may not cause harm
Adverse drug event (ADE): An injury caused by a medication or failure to administer an intended medication. May or may not cause harm. May or may not be preventable. Includes all ADR and expected side effects of the drug
Medication Error: Any preventable ADE involving inappropriate medication use by a patient or health care professional; may or may not cause patient harm
Resistance: The ability to oppose
Teratogenicity effect: effect from maternal drug administration that causes the development of physical defects in a fetus.
Drug abuse: It is inappropriate intake of substance either continually or periodically.
Drug dependence: It is an individual’s physiological or psychological reliance on or need to take a drug or substance
Drug habituation: It denotes a mild form of psychological dependence. The habituated individual develops the habit of taking the substance and feels better after taking it
Tolerance: An increase in dosage may be needed to cause a therapeutic effect in persons with low metabolism in response to a drug
Generic name: When a drug is approved by the Food and Drug Administration it is given a generic (official) name and a trade (proprietary or brand) name.
The trade name is developed by the company requesting approval for the drug and identifies it as the exclusive property of that company.
OTC: Over the counter, no restriction by the FDA
Legend drug: prescription drug, because of possible harmful side effects if taken indiscriminately include birth control pills
Controlled substance: drug controlled by prescription requirement because of the danger of addiction or abuse.
1.2 During preparing and administering the medication, there are principles to follows;
Drug therapy plays a major part in the treatment of patients. It is the nursing responsibility to ensure safe and reliable administration and to monitor side effects.
PHASE ONE: PHARMACEUTICS
Dosage form design determines the rate of at which drug is dissolved and absorbed in the body. It involves two phases:
i) DISINTEGRATION
ii) DISSOLUTION
DEFINITION OF TERMS:
DISINTEGRATION – the breakdown of tablet or capsule into smaller parts
DISSOLUTION – dissolving of the smaller particles in the gastrointestinal fluid before absorption
RATE LIMITING – the time it takes the drug to disintegrate and dissolve to become available for the body to absorb it
After ingestion, a solid drug (tablet or capsule) must first disintegrate into smaller particles.
- Then the smaller particles are to dissolve into a liquid which is ready for absorption in the gastrointestinal tract.
Always remember that…
Drugs in liquid form are more rapidly available for GIT absorption than solids.
Generally, drugs are both disintegrated and absorbed faster in acidic fluids with a pH 1 or pH 2 rather than alkaline fluids.
Young and elderly have less gastric acidity, therefore drug absorption is generally slower for those drugs that are absorbed primarily in the stomach.
Food in the G.I. Tract may interfere with the dissolution and absorption of certain drugs. Some foods can also enhance absorption of other drugs; thus, some drugs should be taken with food.
Enteric-coated drugs do not disintegrate in the stomach since they are formulated to withstand gastric acidity
Disintegration of enteric-coated tablets or capsules only occurs when they reach an alkaline environment like the small intestine.
These tablets or capsules should never be crushed.
Topical applied dosage forms work directly on the surface of the skin
- Other topical dosage form, the skin acts as a barrier through which the drug must pass to get into circulation
Example: fentanyl transdermal patch for pain
Dosage forms administered via injection = parenteral forms
must have certain characteristics to be safe and effective
-> if too concentrated or corrosive, can damage arteries and veins
pH of injections must be similar to blood pH
100% absorption occurs in IV route
PHASE TWO: PHARMACOKINETIC
is what the body does to a drug
-> how a drug is altered as it travels through the body
-> the process of drug movement to achieve drug action and the study of the concentration of a drug during its 4 process (absorption, distribution, metabolism or biotransformation and excretion)
Properties that Influence Pharmacokinetic Activity:
I) Physiochemical Properties of Drugs
In general, drugs exist as weak acids or weak bases.
-They appear in either ionized or non-ionized form.
II) Physicochemical Properties of Cell Membrane
- The membrane consists of a bimolecular layer of lipids that contain protein molecules which are irregularly dispersed throughout the lipid bilayer.
- The protein molecule may act as a carrier, an enzyme, a receptor or an antigenic site
- Drugs that are lipid (fat) soluble can pass through the lipid membrane, but those that are water soluble cannot.
- In this instance, the membrane which appears to contain pores permits the passage of small water-soluble substances such as urea, alcohol, electrolytes and water itself
- Drug molecules that are free are transported from one body compartment to another by way of the plasma.
- However, these movements are limited because various sites are enclosed by membranes.
- Barriers to drug transport may consist of single layer of cell (such as the villus in intestinal epithelium) or several layers of cell (such as skin).
* Nevertheless, in order for the drug to gain access to the interior of a cell or a body compartment, it has to penetrate cell membranes
PHARMACOKINETIC ACTIVITIES
I) ABSORPTION
- the process that involves the movement of drug molecules from the site of entry until it reaches the circulating fluids & tissues.
- the movement of drug particles from the G.I. tract to body fluids by passive absorption, active absorption, or pinocytosis.
Variables That Affect Drug Absorption
a. Nature of the absorbing surface (cell membrane) through which the drug must traverse.
b. Blood flow in the site of administration.
c. Solubility of the drug.
d. Acidity of the stomach
e. Drug concentration.
f. Dosage form
Routes of Drug Administration
- Classified into:
Enteral (via the GIT):
Methods used in giving drugs:
a) oral
b) sublingual
c) buccal medications
Advantages:
-Safest (because it can be retrieved)
-Most convenient and economical route of administration
Disadvantages:
-Most unreliable
-Oral administration can lead to inactivation of certain drugs
-> e.g. Penicillin G cannot be taken orally because it would be destroyed by stomach acid)
Patient requirements:
# Conscious and cooperative patient.
-> Drugs cannot be administered to comatose individual or individual who for whatever reason (psychosis, seizures, etc.) are unable or unwilling to swallow medication
# Local Irritation.
- Some oral preparations cause local irritation of the GIT, which can result to discomfort, nausea and vomiting (e.g. aspirin)
# Rapid absorption in small intestine
# Presence of food diminishes absorption
# Absence of food increases absorption
# Liquid absorb more rapidly than solids
Absorption occurs within 3 to 5 min. with SL or buccal
Increased intestinal motility decreases available time of absorption
Absorption through the GI tract may be undependable
A) Oral preparation: Troche (lozenges)
flat, round or oval preparation that dissolves and releases a drug when held in mouth
Not for digestion.
B) Parenteral Route: Refers to the administration of drugs by injection.
It is the most rapid form of systemic therapy.
Types:
a) subcutaneous:
- Injection into the connective tissue or fat immediately underlying the dermis the site can be used only for drugs that are not irritating to the tissue
- the rate of absorption is slow and can provide a sustained effect
- have effects within 10 to 15 min
b) intramuscular:
- injection into the skeletal muscle
- absorption occurs more rapidly than with subcutaneous injection because of greater tissue blood flow
c) Intravenous:
- immediate pharmacologic response because the desired concentration of the drug is injected into the bloodstream
- drugs should be administered slowly to prevent adverse effects
- requires no absorption; effect is immediate
d) Intrathecal:
- injection directly into the spinal subarachnoid space, bypassing the blood-brain barrier
- when rapid effects of drugs are desired, as in spinal anesthesia or in treatment of acute infection of the CNS
- has effects within 10 to 15 min.
- Poor circulation may hinder IM or SQ absorption
- Shock, edema, trauma, and coolness to tissue slow absorption
- Massage and heat tissue increase absorption
C) Pulmonary Route:
- to ensure that normal gas exchange of oxygen and carbon dioxide is continuous in the lungs, drugs must be in the form of gases or fine mist (aerosols) when they are administered by inhalation
- the lung provides a large surface area for absorption
-the rich capillary network adjacent to the alveolar membrane promote ready entry of medication into the bloodstream
D) Inhalation:
- May be absorbed systemically; analgesic agents
- May be absorbed locally; corticosteroids
- Absorption enhanced because of the large surface area
E) Topical: applied topically to the skin and mucous membrane
- usually drugs applied to the skin are employed as topical remedies to produce a local effect.
- Only lipid-soluble compounds are absorbed through the skin.
Eyes: administration of drops into the eyes produces a local effect on the conjunctiva or anterior chamber.
- Eyeball movement promote the distribution of drugs over the surface of the eye
Ears: Administration of drops into the auditory canal may be chosen to treat local infection or inflammatory conditions of the external ear.
Suppository: Drugs mixed with gelatin and shaped for insertion in to a body cavity (eg: rectum), the base dissolves gradually at body temperature, releasing the drug
Pessary-is a small plastic or silicone medical device which is inserted into the vagina or rectum and held in place by the pelvic floor musculature for local effects
e.g. Nystatin Pessary
II) DISTRIBUTION
- it is the transport of a drug in body fluids from the bloodstream to various tissues of the body and ultimately to its site of action.
Factors affecting distribution:
DRUG’S LIPID SOLUBILITY- those that are not lipid soluble cannot pass through
PERFUSION OF REACTIVE TISSUES
-Rich perfusion: heart, liver, kidney and brain
-Poor perfusion: fat, muscle
DRUG RESERVOIRS
Storage reservoirs allow a drug to accumulate by binding to specific tissue in the body. This sustains the pharmacologic effect of a drug at its point of action.
- 2 General types of drug pooling:
a) Plasma protein binding: on entry into the circulatory system, drugs become attached to proteins (mainly albumin). Thus, free drugs enter the plasma. Binds to the protein to form a drug-protein complex.
Free drug + Protein = Drug protein complex
-The formula indicates that equilibrium is established between the amounts of free drug (drugs not bound to protein) and amount of drug that is bound to protein (drug-protein complex).
DEGREE OF DRUG BINDING
-Plasma protein binding (primarily with albumin) is expressed as a percentage, which refers to the percentage of total drug that is bound.
4 Categories
1) Highly Protein-bound: Drugs that are greater than 89% bound to protein
2) Moderately Highly Protein-bound: Drugs that are 61-89% bound to protein
3) Moderately Protein-bound: Drugs that are 30-60% bound to protein
4) Low Protein-bound: Drugs that are less than 30% bound to protein
Competition for binding sites.
-albumin and other plasma proteins provide a number of binding sites
- two drugs can compete with one another for the same site and displace each
E.g. Warfarin, an anticoagulant, if simultaneously given Aspirin an analgesic
b) Tissue Binding:
Fat tissue- lipid soluble drugs have a high affinity for adipose tissue. Relatively low blood flow in fat tissue makes it a stable reservoir e.g. Thiopental stays in low concentration in body fat for as long as 3 hours
Bone- Usually some drugs have an unusual affinity with bones. It is stored in the crystal lattice of bone for discoloration
Blood brain barrier: special anatomical arrangement that allows distribution of only lipid soluble drugs (e.g. general anesthetics, barbiturates)
Placental Barrier; tissue enzyme in placenta can also metabolize agents (e.g. catecholamines). Unlike blood brain barrier, it is less selective. (e.g of drugs that can cross the placental barrier: steroids, narcotics, anesthetics and antibiotics)
Fetal drug effects
- 1st trimester: teratogenic effect- physical defects in developing embryo
III) BIOTRANSFORMATION or METABOLISM
Activates a drug by converting (transforming) it into a more water-soluble compound or metabolite, that can be excreted from the body
Liver- primary site of metabolism of drugs
Other sites of metabolism include the plasma, kidneys, lungs and intestinal mucosa
Hepatic biotransformation
- The chemical alterations are produced by microsomal enzyme system, located largely in the liver, which consist of endoplasmic reticula, a series of membrane that appears as a network of canals within the cells
Hepatic first pass effect
orally administered drugs absorbed from the GIT normally travel first to the portal system.
-> However, some drugs may first be taken up by the hepatic microsomal enzyme system so that a significant amount is metabolized before the drug ever reaches the systemic circulation.
Factors that decrease metabolism:
· Cardiovascular dysfunction
· Renal insufficiency
· Starvation
· Obstructive jaundice
· Slow acetylator
· Erythromycin or ketoconazole drug therapy
IV) EXCRETION
A process whereby drugs and pharmacologically active or inactive metabolites are eliminated from the body, primary though the kidneys
Organs of excretion:
1. Kidneys;
· Glomerular Filtration= filtration moves drugs from blood to urine. Protein-bound drugs are not filtered only free, unbound, water soluble and metabolites
· Active tubular reabsorption= occurs at the level of the tubules. Substances are taken back up into the circulation and transported away from the kidneys. This is the body’s attempt to retain needed substances
· Tubular secretion= secretion of substances into the nephron from the blood vessels, surrounding it.
· Urinary pH= (4.6-8.2) affects the amount of drug reabsorbed in the renal tubule by passive diffusion
· Weak acids are secreted more readily in alkaline urine
· Urine pH may be altered
· Made more acidic with Vitamin C or Ammonium chloride resulting to increase excretion of basic drug
· Made more alkaline with sodium bicarbonate resulting to increase excretion of acidic drugs
Dialysis-substances that are completely or almost completely excreted by kidneys. It can be removed by hemodialysis. Causes rapid reduction of increase plasma levels of a drug.
2. Intestines
· after metabolism by the liver, the metabolite is secreted into the bile and passed into the duodenum. It is eliminated with the feces.
· Certain drugs such as fat-soluble agents may be reabsorbed by the bloodstream and returned to the liver. -> known as the enterohepatic cycletestines
3. Lungs
· most drugs removed by pulmonary route generally intact and not metabolized.
· Process: inspiration leads to the alveolar membrane to the bloodstream. Upon excretion from alveolar membrane results to excretion. (Increase RR= increase excretion
4. Sweat & salivary glands
· Excretion of drugs through sweat and saliva is relatively unimportant.
è This process depends on diffusion of lipid-soluble drugs through the epithelial cells of the glands
5. Mammary glands
· many drugs cross the epithelium of breast tissues. Breast milk is acidic.
· Basic compounds have increase concentration in breast milk (e.g morphine).
· While weak acids are less concentrated
Pharmacokinetic Considerations
Onset: The time it takes for the drug to elicit a therapeutic response
Peak: The time it takes for a drug to reach its maximum therapeutic response
Duration: The time a drug concentration is sufficient to elicit a therapeutic response
PHASE THREE: PHARMACODYNAMIC
· It is the study of the mechanism of drug action on living tissues
1.3 PRINCIPLES OF DRUG ACTION
1. Drugs do not create new cellular functions but alter existing ones
- Drugs may interact with the body in many different ways - some act by altering chemical composition of a body fluid
- Different drugs with molecules precisely fit into a given receptor (e.g., penicillins)
- Drugs don’t confer any new functions on a body tissue/organ. They only modify existing functions
- They do not stop the function of the body tissue but it allows it even more and modifies existing function
- It will not give a new function to the tissue /organ
Examples
Cathartics: compensate the role of large intestine
Atropine Sulfate: given before surgery (interrupts salvation in the pre-op patients)
2. Drug action results from a Physio Chemical Interaction between the drug and a functionally important molecule in the body
- Combine with macromolecular tissue components (major mechanism) receptors (Beta 1- acts more on heart and Beta 2- acts more on lungs)
- Combine with small molecules (Example: antacids will neutralize gastric acids)
- Alter cell membrane action (Example: Local anesthetics)
Therapeutic effect: a positive change in a faulty physiologic system (the goal of drug therapy)
Mechanism of Action
Once the drug is at the site of action, it can do either one of the two ways:
1. modify (increase or decrease) the rate at which that cell or tissue functions
2. modify the strength of function itself of that cell or tissue
3 Basic Ways of Drug Actions
· Through receptors
· Through enzymes
· Through nonselective interactions
1. Drug-Receptor Interactions
Receptor – a reactive site on the surface or inside of a cell
Affinity – the degree to which a drug attaches to and binds with a receptor
Efficacy – the ability of the drug to initiate biologic activity as a result of binding to a given receptor
Agonist – a drug that combines with receptors and initiates a sequence of biochemical & physiologic changes
Partial Agonist – an agent that has affinity some efficacy but may antagonize the action of other drugs that have greater efficacy
Antagonist – an agent designed to inhibit or counteract the effects produced by other drugs
Competitive Antagonist - an agent with an affinity for the same receptor site as an agonist
Noncompetitive Antagonist: an agent that combines with different parts of receptor mechanism & inactivates the receptor so that the agonist cannot be effective regardless of its concentration
What is a Drug-Receptor Interaction?
- This theory hypothesizes that drugs are selectively active substances with a high affinity for a specific chemical group or a particular constituent of a cell
2.Drug-Enzyme Interactions
- also called selective interaction
Enzymes = substances that catalyze nearly every biochemical reaction in a cell
Antimetabolites = drugs resembling enzyme substrates
What is a Drug-Enzyme Interaction?
- It occurs when the drug chemically binds to an enzyme molecule in such a way that it alters the enzymes interaction with its normal target molecules in the body.
- Antimetabolites can either block normal enzymatic action or result in the production of other substances with unique biochemical properties.
3. Nonselective Interactions
- Drugs with this action target the cell membranes and various cellular activities by either:
* interfering physically or * altering chemically
What is Nonspecific Drug Interaction?
- Drugs with this mechanism of action incorporate themselves into the normal metabolic process, thus causing a defect in the final product or state.
PHARMACOGNOSY
· The study of natural (plant and animal) drug sources
Why study drug sources?
· To identify chemical features of a substance that produce a desired clinical response
· To gain understanding of the actions and effects of natural drug sources is essential to new drug development
Main Sources of drugs:
Plants
Animals
Minerals, and
laboratory synthesis
SELF CHECK 1.1
1. Define different terminology.
2. Explain the pharmacokinetic process.
Topic 2: Drug Control
LEARNING OUTCOMES
At the end of the topic, students should be able to;
1. Define the Poison and Control Substances.
2. Explain the Act of poison and Control Substances.
3. Explain the storage and proper documentation.
• Poison Ordinance / Dangerous Drugs
Controlled Substances Act: A federal law that regulates the prescribing and dispensing of psychoactive drugs, including narcotics, hallucinogens, depressants, and stimulants.
Dangerous Drugs Act 1952 (Act 234)
An Act to make further and better provision for the regulating of the importation, exportation, manufacture, sale, and use of opium and of certain other dangerous drugs and substances to make special provision relating to the jurisdiction of courts in respect of offences there under and their trial, and the purposes connected therewith.
The Controlled Substances Act is designed to remedy the escalating problem of drug abuse including:
- the promotion of drug education and research into the prevention and treatment of drug dependence
- the strengthening of enforcement authority
- the establishment of treatment and rehabilitation facilities
- the designation of schedules, or categories, for controlled substances according to abuse liability
Schedule Categories of Controlled Substances
Signs of drug Abuse
ü Problems remembering things you recently said or did
ü Getting drunk on a regular basis
ü Lying about how much alcohol you are drinking
ü Thinking that drug is necessary to have fun
ü Having frequent hangovers
ü Feeling run-down, depressed, or even suicidal
ü Having "blackouts"--forgetting what you did while drinking
ü Having problems at work or getting in trouble with the law
The Ten Most Dangerous Substances
1. Heroin - popular street names include smack, skag, and junk.
2. Cocaine - often referred to as snow, flake, coke, and blow.
3. Barbiturates - popular slang names include yellow jackets, reds, blues, Amy's, and rainbows.
4. Street Methadone
5. Alcohol
6. Ketamine - a powerful hallucinogen, often referred to as Special K.
7. Benzodiazepines - a family of sedative drugs.
8. Amphetamines - known as greenies among baseball players.
9. Tobacco
10. Buprenorphine
Other abused substances:
1. Cannabis - includes marijuana
2. Solvents - volatile substances that can be inhaled, such as glue, nail polish remover, paints, hair spray, and lighter fuel (gas).
3. 4-MTA - is a derivative of amphetamine and has similar effects to ecstasy.
4. LSD
5. Methylphenidate - central nervous system stimulant, commonly sold as Ritalin.
6. Anabolic steroids
7. GHB - short for Gamma hydroxybutyrate, a powerful central nervous system depressant, most commonly known as the date rape drug.
8. Ecstasy
9. Alkyl nitrates - group of drugs commonly referred to as poppers.
10. Khat - an amphetamine-like stimulant.
Goals in Handling Controlled Substances
1. To provide a controlled method for acquisition and dispensing of controlled substance.
2. To maintain appropriate proof of use
3. documentation in a retrievable manner.
4. To maintain a high level of security in the storage of controlled substances.
5. Nursing Interventions on Controlled Substances
6. Account for all controlled drugs.
7. Keep special controlled substances record for required information
8. Countersign all discarded or wasted medication.
9. Ensure that records and drugs on hand match
10. Keep all controlled drugs locked up, narcotics must be kept under double lock.
11. Be certain that only authorized persons have access to the keys.
• Documentations
All usage of controlled substances will be documented appropriately on the controlled substances documentation sheet or DDA book
DDA book consists of this following information:
· Date
· Name of client and RN
· Name of Dr ordering the controlled substance
· Signature of the nurse administering the medication
· Name of drug dosage form
· Amount given
· Balance on hand
In the event of an inaccurate count:
-Report immediately
-Remain on duty and search for missing narcotics
-Sign list as incorrect
-Fill out incident report and sign with one witness
If one part of a pre-measured dose of drug is given, a second nurse witnesses disposal of the unused portion and documents such on the DDA book
In some hospitals the empty ampule is required to be returned to the pharmacy
In the event of wastage or breakage of controlled substances, it must be documented in the DDA book
The nurse must state:
The date of event
Reason for wastage eg. Accidentally broken, expired or return to pharmacy
Amount wasted
Signature of the nurse wasting the substance
Signature of witness
• Storage
Dispensed to the ward using the stock supply or floor stock
Controlled substances must be stored under a double lock system
POISONS: Substance on which ingestion, inhalation, absorption, application, injection or development within the body, relatively small amount, may cause structural damage or functional disturbance
Poison a substance that if ingested even in very small amounts can harm or kill living things.
There are some substances that are considered poisonous even they are not classified as poison because they are dangerous only in relatively large amounts.
Toxicology is the study of poisons, how they work, their effects on the body, and the treatment of the conditions.
How Poison Works
Corrosive and irritant poisons like strong acids destroy or inflame the cells they contact.
Metabolic poisons like gases and drugs (that are toxic in overdose) act mainly by disrupting the body's chemical reactions.
Type of Poisons
Hydrocyanic (prussic) acid is one of the most rapidly acting toxins which affects mammals, this toxin acts in seconds.
Metallic compounds like mercury (commonly used in dental filling) and lead if ingested in small doses, may accumulate in the body for years before causing illness or death.
Botulinus toxin is the deadliest poison, it is secreted by a bacillus that causes food poisoning. It is deadly even in extremely small amounts.
Symptoms of Poisoning:
è Smell of poison on the breath
è Burning sensation in the throat.
è Vomiting and dizziness
è Poisoning may also be the cause if the person suddenly becomes ill, faint, and acts in a confused manner.
How to manage poisoning?
Check for signs and symptoms of poisoning. Some of the more common symptoms include:
§ Nausea and vomiting
§ Diarrhea
§ Abdominal pain
§ Burns or redness around the mouth
§ Unconsciousness, or slipping into unconsciousness
SELF-CHECK 2.1
1. Define Poison and Control Substances
2. How to do proper storage and documentation.
Topic 3: Classifications of Drug
LEARNING OUTCOMES
At the end of the topic, students should be able to;
1. Explain responsibilities and implications during administration
2. Explain legal aspects of drug administration and implications in nursing practice.
Scope of Nursing Responsibilities
1. Nurses are liable for action and omission and duties delegated to others.
2. Nurses have a legal, moral and ethical responsibility for every drug they administer.
3. The law requires health professional to be safe and competent practitioners and permits compensation to those harmed or injured.
4. Actions that safeguard patients from drug-induced injury includes:
è Use correct techniques or precautions.
è Observe for and chart drug-effects explicitly.
è Keep their knowledge base current
è Refer to authoritative sources
è Question a drug order that is unclear or appears to be erroneous.
è Refuse to give a drug or refuse to allow others to order or administer a drug that may be harmful to the patient.
5. Nurses are entrusted with potent and habit-forming drugs.
6. Nurses must establish a therapeutic alliance with the client and a respectful and trusting relationship to facilitate the highest level of self-care attainable.
7. Although there are hundreds of drugs available, a knowledge base can be established by studying a drug that is representative of each classification.
8. Clinical experience is a useful tool in learning because it enables the student nurse to:
§ Note which drugs are commonly used to treat disease specific s/s.
§ Observe which drugs are most effective in relieving s/s.
§ Note the frequency with which certain drugs are administered.
§ Witness individual differences in client’s different reactions to a specific drug.
§ Relate knowledge to real life situations
Implementation: Preparing Drugs for Administration
1. Ensure cleanliness of your hands, work area, and supplies.
2. Ensure availability of supplies.
3. Ensure adequate lighting.
4. Decrease environmental distractions.
Remember the Rights of Medication Administration
1. The Right Drug
After checking the order, the nurse selects the right medication.
When using a non-unit dose system, the label on the container should be read three times: when taking the container from its location, when removing the medication from the container, and when returning the container to its storage place. For unit dose administration, the three checks should be carried out.
These are checking the medication
1) when removing it from its location in the drawer, bin, or refrigerator
2) when comparing it to the client’s medication administration record; and
(3) before administering it to the client. Use special care when administering drugs whose name sounds like another drug. Never use medication from a container that is unlabeled or whose label is illegible or defaced.
NURSING IMPLICATION:
1. Carefully check the order.
2. Check the medication against the order.
3. Do not administer a medication someone else has prepared.
4. If using a unit dose system, do not open the unit packaging until you are at the client’s bedside.
Safe administration of the right medication requires that the nurse become familiar with basic information about the drug, including its action, contraindications for use, usual dosage, and side effects. To accomplish this, current reference books should be available on the nursing unit.
2. In the Right Dose
Determining the correct amount of a drug is sometimes difficult because three measurement systems are used in ordering medications. The nurse must be familiar with household measures, the apothecary system, and the metric system and must be able to convert from one system to another
To prepare the right amount of medication, the nurse must have developed skills in using measuring devices such as medication cups, droppers, and syringes. When preparing a liquid medication for oral administration, shake all suspensions and emulsions to ensure proper distribution of the ingredients. Examine the measuring device. Most have measurements for the three systems: for example, a metric measure (mL) for milliliters; an apothecary measure (oz) for ounces; and a household measure (tsp and tbsp) for teaspoon and tablespoon, respectively.
NURSING IMPLICATION:
2.1. Be familiar with the various measurement systems and the conversions from one system to another.
2.2. Always use the appropriate measuring device and read it correctly (e.g., measure liquids for oral administration at the meniscus).
2.3. Shake all suspensions and emulsions.
2.4. When measuring drops of medication with a dropper, always hold the dropper vertically and close to the medication cup.
2.5. When removing a drug from a multiple dose vial, inject an amount of air equal to the amount of fluid to be withdrawn.
2.6. Do not attempt to divide unscored tablets and do not administer tablets which have been broken unevenly along the scoring
3. To the Right Client
Once the medication has been properly prepared, the next step is to identify the right client. Although techniques suggested for identifying the right client might seem unnecessary to the student assigned to administer medications to only one client, it is important to understand and practice the principles to avoid errors when administering medications to several clients. Nurses, therefore, should make it a habit to employ proper identification procedures regardless of the number of clients involved. In general, take every opportunity to be certain that you are administering the medication to the right client. If the client is in bed, check the name tag on the bed. Always check the client’s wrist identification band. If the client is physically and mentally able, ask him/her to state his/her name.
NURSING IMPLICATIONS:
3.1. Check the tag on the client’s bed.
3.2. Check the client’s identification band.
3.3. Ask the client to state his/her name.
3.4. Ask parents to tell you the name of their child.
3.5. Address the person by name before administering the medication.
3.6. Always double check orders that the client questions.
4. At the Right Time
The prescriber’s order will specify the number of times a day the medication is to be given. It may also state the exact hours of administration or give general guidelines such as directions to administer with meals or before meals. If no exact time is given, drug administration is frequently planned according to a standard agency administration schedule. Medication administration schedules are based on knowledge of the desired effect of the drug, the characteristics of the drug itself, possible interactions with other drugs, and the client’s daily schedule.
The schedule established for drug administration is important, and the nurse adheres to the schedule. A routine schedule helps to prevent administration of doses too close together or too far apart and is important in maintaining a relatively constant blood level of drugs that are given several times a day. As a general rule, the nurse should always be certain that a medication is administered within 1⁄2 hour of the time it is ordered to be given.
NURSING IMPLICATIONS;
4.1. To achieve maximum therapeutic effectiveness, medications are scheduled to be administered at specific times.
4. 2. The nurse should adhere, as closely as possible, to the scheduled time(s) of administration.
5. By the Right Route
The right route includes the correct route of administration, and administration in such a way that the client is able to take the entire dose of the drug and receive maximal benefit from it. The physician will usually specify the route by which the medication should be administered. If none is specified, the oral route is often intended, but for safety the nurse should check with the prescribing physician. However, any questions about the medication order should be discussed with the prescriber before administration of the first dose.
Drugs may be administered in a variety of ways. Not all drugs may be administered by all of the possible methods. Many drugs, however, are available in several forms, permitting administration by more than one route. The method by which a drug is administered affects such factors as the absorption, speed of onset, dose, and side effects.
Although nurses may not be responsible for administration by all of these routes, they need to be familiar with the terminology. Nurses assist physicians in administration of drugs by some of these routes, e.g., intraarticular. When assisting a physician in administering a medication, the nurse ensures that the seven rights of administration are followed.
Common Routes of Drug Administration
PRIMARILY FOR LOCAL EFFECTS
topical application—to mucous membranes or skin
intra-articular—within the cavity of a joint
intracardiac—into a chamber of the heart
intradermal or intracutaneous—into the dermal layer of the skin
intrathecal—into the spinal fluid
inhalation—into the respiratory tract
PRIMARILY FOR SYSTEMIC EFFECTS
By the gastrointestinal tract: buccal or transmucosal—in the cheek
oral—by mouth
sublingual—under the tongue
rectal—in the rectum
By injection: intramuscular—into a skeletal muscle
intraosseous—into the bone marrow
intratracheal—into the trachea
intravenous—into a vein
subcutaneous—into the subcutaneous tissue
The extra care taken by the nurse to ensure that the seven rights are adhered to may help to prevent mistakes, which can occur particularly when other staff members performing administration procedures are not as familiar with the client’s history and condition as the nurse is. The nurse retains responsibility for the drugs he/she prepares for administration. If the nurse has concerns about the safety of administering a particular drug to a particular client or about the route of administration, the physician should be asked to prepare and administer the medication, as well as to record the procedure on the client’s record. It is also important to provide information and support for the client during procedures that may be uncomfortable, such as intrathecal administration of medications. Always be certain to record the procedure and the client’s ability to tolerate the procedure on the client’s record. Administering a drug so that the client is able to take the entire dose and receive maximal benefit from it includes several nursing activities: 1. The nurse must gain the client’s cooperation. Explanation about the administration procedure should be given and the client’s ability to understand must be considered.
2. Special administration techniques may be required because of the client’s developmental level.
3. Some medications are administered in such small amounts or have such an unpleasant taste that they must be diluted or mixed in another vehicle, such as juice, in order for the client to take the entire dose. It is important for the nurse to know with which liquids specific drugs may be mixed without significantly altering the properties or actions of the drug. Consult with a pharmacist if questions arise about drug-vehicle compatibility.
4. If several drugs are to be administered at the same time, the order in which the nurse administers these drugs may be important. For example, it may be difficult for the client to turn for an injection. In this situation, oral medications should be administered first, followed by the injection and positioning of the client for maximum comfort. Also, some drugs have a local soothing effect on mucous membranes of the mouth or throat. Such drugs should be administered following other oral medications and should be followed by little or no water.
As a general guide, when administering oral medications, the sequence used would be:
(1) drugs that require special assessments, such as those for which an apical pulse or blood pressure assessment is required;
(2) other tablets and capsules;
(3) liquid preparations except for syrups intended for local soothing or anesthetic actions;
(4) sublingual preparations; and
(5) antacids and liquid preparations intended for local soothing or anesthetic actions which are given with instructions not to eat or drink fluids for 20 to 30 minutes.
NURSING IMPLICATIONS:
5.1. Be sure you know the prescribed route by which a medication is to be administered.
5.2. If no route is specified in the physician’s order, the prescribing physician should be questioned about the intended route.
5.3. Always gain the client’s cooperation before attempting to administer a dose of medication.
5.4. Consider the client’s developmental level during administration of medications.
5.5. The nurse must know what vehicles may be used with various drugs.
5.6. To achieve maximum effectiveness and client well-being, it is important to plan the order in which medications are administered.
6. Right Documentation
The right documentation includes the drug, the dosage administered, the time administered, the route and site if given parenterally, and the client’s response. Most facilities have an MAR for documenting this information; however, if the client is being medicated at home, this information may be documented on the client’s anecdotal note.
The right documentation is not only a legal requirement, but also a safety responsibility of the nurse. It is the primary method used to communicate medication administration from one nurse to the next nurse caring for a specific client. The basic principle of documentation is “if it isn’t documented, it wasn’t done.” Consequently, if the nurse does not document that a particular medication was given, a second dose may be administered by another nurse, causing the client to experience adverse reactions, even life-threatening responses.
NURSING IMPLICATIONS:
6 1. Be sure to document the medication and time administered on appropriate facility document.
6.2. Document site location after administering intradermal, subcutaneous, or intramuscular injection.
6.3. Document if client refuses medication, client’s reason, and reporting of refusal to physician.
7. Client Right to Refuse
The client has the right to refuse to have a medication administered. Without the client’s permission (or the permission of the legal guardian in the case of a pediatric client or a client unable to give permission who has a legal guardian), the nurse providing any treatment, including administering medications, is potentially at risk for legal complications. Because the nurse is the health care professional who most often is the one administering the medications, addressing client refusals is an important nursing function.
Most refusals by clients are the result of the client’s knowledge deficit about what the medication is and what it does. When a client refuses to take a medication, the nurse’s first action should be to assess the client’s reason for the refusal. Addressing the client’s lack of understanding of the medication will usually result in the client’s compliance.
A proactive nursing approach is to always inform all clients about their medications before attempting to administer them. Some client refusals result from the health care professionals’ lack of knowledge of a client’s allergy to the medication that the physician was unaware of when the medication was prescribed. The physician should immediately be notified about the client’s refusal and the presence of the client’s allergy. The physician will then reassess the medication order. Other refusals are due to the client experiencing adverse effects of the medication.
For example, a client receiving a laxative or stool softener for constipation begins to have loose or diarrhea stools and refuses the next dose of the medication. This is a legitimate reason for not administering the medication and contacting the physician for an order change. Some refusals are the result of the client’s feeling powerless either because of being in an acute care facility or because of the health alteration that precipitated the need for the medication. Again, this information can be retrieved from the nurse’s assessment done as a result of the client’s refusal.
NURSING IMPLICATIONS:
The Client’s Right to Refuse
7.1. Be sure to assess client’s reason for refusing medication.
7.2. If knowledge deficit underlies client’s reason for refusal, provide appropriate explanation for why medication is ordered, what medication does, and the importance of medication for treatment of client’s health alteration.
7.3. Document if client refuses medication, client’s reason, and reporting of refusal to physician.
Cultural, Legal and Ethical Considerations for Nursing Practice
Nurses need to be knowledgeable about drugs that may elicit varied responses in culturally diverse patients
Pattern of communication
- may differ based on patient’s race or ethnicity
Understanding of health beliefs
- influence how patients respond to drug therapy
- affect patient’s adherence to the drug regimen
Nursing considerations:
1. Develop good IPR and due considerations of their racial-ethnic backgrounds
2. Focus on scientific aspects of patients’ drug therapy rather than asking broad or general questions.
3. Be informed about difference communication patterns across cultures:
§ Chinese=rarely complain or
§ Asians= express problem in behavioral/somatic terms
4. Always consider the patient’s cultural beliefs, attitudes and values when administering medications & in-patient education.
5. Identify any potential conflicts between medications and cultural beliefs.
6. Identify any herbal, complimentary or alternative therapies (home or folk medicines) being used.
7. Be alert to patients’ response to medications.
LEGAL ISSUES
Standard of Professional Nursing Practice
> standards for nursing practice: scope, function and role of the nurse & establish clinical practice standards
ex. Ministry of Health Malaysia: CPGs
=> written policies and procedures
*standards of care help to determine whether the nurse is acting appropriately when performing professional duties
ETHICAL ISSUES
Based on fundamental principles:
Beneficence
The ethical principle of doing or actively promoting good, related nursing actions include determining how the patient is best served
Autonomy
Self-determination and the ability to act on one’s own related nursing actions include promoting a patient’s decision-making, supporting informed consent, and assisting in decisions or deciding when a patient is posing no harm to himself or herself.
Justice
The ethical principle of being fair or equal in one’s actions, related nursing actions include ensuring fairness in distributing resources for the care of patients and determining when to treat.
Veracity
The duty to tell the truth; related nursing actions include telling the truth with regard to placebos, investigational new drugs and informed consent
Confidentiality
The duty to respect privileged information about a patient; related nursing actions include not talking about a patient in public or outside the context of the health care setting
Non-maleficence
the duty to do no harm to a patient
related nursing actions: avoiding doing any deliberate harm while rendering nursing care
What is Medication Error (MEs)?
- a specific type of clinical problem
- a subset of adverse drug event
- potentially preventable
- common cause of adverse healthcare outcomes
- ranges in severity from having no significant effect to patient disability or death
What to consider?
Medication Administration
System Analysis Process
-examines the entire HC delivery system; health professional involved; and any other factor that has impact on the error
Factors that lead to MEs:
è Increasing number of drugs on the market
=> increasing number of drug names to keep track of
ex. SALAD= sound-alike, look-alike drugs
LASA= look-alike, sound alike drugs
è Weakness in the system within healthcare organizations
- failure to create a “just culture”
- excessive workload with minimal time for staff prevention education
- lack of interdisciplinary communication and collaboration
Psychosocial Issues that Contribute to Errors
1) Organizational Issues
- a study found, 50% of all ADRs begin at the prescribing stage
- presence of a pharmacist during medical rounds reduce the incidence of errors
- effective use of technologies (computerized prescriber)
- bar coding of medication packages
2) Educational System Issues
- rigorous cognitive and even physical challenges of HC study and practice, attract strong-willed intelligent people
=> expectations that one be smart and on top of things with clinical knowledge
=> denial, fear or shame about being wrong or not remembering a piece of information while on duty
How to address this issue?
Authoritative Sources
- current drug reference guides (less than 5 yrs. old)
examples: Mosby’s Drug Consult
Forward-Thinking Faculty Members
- learning is a life-long process
- adopting philosophy of “no question is a stupid question”
- allow staffs to begin career with greater confidence & with a healthy habit of self-monitoring during healthcare delivery
PREVENTING, RESPONDING TO, REPORTING & DOCUMENTING MEs
Preventing MEs
- any preventable event that can lead to inappropriate medication use or harm while the medication is in the control of the professional nurse, student nurse, health professional, prescriber, patient or consumer.
Strategies that can prevent MEs:
1. Multiple systems of check and balances.
2. Prescribers should write legible orders with accurate information or electronically if available.
3. Consult authoritative resources: pharmacists or current drug literature.
4. Nurses should always do “three checks” before giving the drug and consult authoritative resources.
5. Consistent use of the “Six Rights” of medication administration.
Responding to, Reporting and Documenting MEs
- a professional responsibility for which a nurse is accountable
- if an error has occurred, it must be reported
- facility policies and procedures for reporting and documenting the error should be followed closely and cautiously
Steps for the nurse to take:
1. Assess patient and attend to urgent issues of safety.
2. Report error immediately to appropriate prescriber and nursing management personnel (ex. Nurse manager or supervisor)
3. Have a fellow nurse or other qualified healthcare professional remain with the patient if pt. condition is deteriorating or close monitoring is needed.
4. Implement follow-up procedures or tests as indicated by the prescriber (ex. Antidote administration)
reminder: Highest priority at all times is, patient’s physiologic status and safety.
5. Nurse should complete all appropriate forms – including an incident report and provide needed documentation
How to document?
- only factual information about the error
- should be accurate, thorough and objective
- use of judgmental words such as “error” should be avoided
- document factual information such as:
a) medication administered
b) actual dose given
c) other details regarding the order (ex. wrong route, wrong patient and/or wrong time)
- any observed changes in the patient’s physical and mental status
- document prescriber notification, follow-up actions or orders
- patient monitoring which should be ongoing
Performing Medication Reconciliation
- a process that seeks to prevent medication errors through:
> ongoing assessment and updating of information on patient’s medication throughout the healthcare process
> timely communication of this information to both patients and their prescribers
3 Steps in Medication Reconciliation:
1. verification= collection of patient’s information
2. clarification= professional review of information to ensure that medications and dosages are appropriate for the patient
3. reconciliation= further investigation of discrepancies and documentation of relevant communication and changes in medication orders
Applicable Assessment and Education Tips:
1. Start with open-ended questions and gradually move to yes-no questions (details are important or even critical).
2. Avoid use of medical jargon.
3. Prompt patient to try to remember all applicable medications.
4. Clarify all unclear information to the extent possible.
5. Record the foregoing information in the patient’s chart as the first step in the medication reconciliation process.
6. Emphasize to the patient the importance of always maintaining current and complete medication list and bringing it to every health care visit.
SELF-CHECK 1.3
1. Explain nurses’ responsibilities and implication during administration.
2. Explain the legal impact to nursing practice.
Topic 4: Major Drugs affecting major organ systems of the human body: Nervous System – central and peripheral
Learning Outcomes
At the end of the topic, students should be able to;
1. Explain the common drug use in nervous system.
2. Differentiate drugs between stimulants and depression for CNS.
3. Explain nursing responsibilities when administering drug use in CNS.
CNS STIMULANTS
May produce dramatic effects by increasing the activity of CNS neurons.
Their therapeutic usefulness is limited because of their many general effects & side effects in the body
Can result to drug tolerance, drug dependence & drug abuse problems
Medically approved is limited to:
* Attention deficit hyperactive disorder (ADHD), NARCOLEPSY, OBESITY, Reversal of RESPIRATORY DISTRESS
Major groups:
1. Amphetamine – stimulate cerebral cortex (anti-ADHD and anti-narcoleptic)
Mechanism of action & drug effects:
Stimulate areas of the brain associated with mental alertness (cerebral cortex and thalamus)
Mimics SNS
CNS effects: mood elevation or euphoria; increased mental alertness and capacity for work; decreased fatigue and drowsiness and prolonged wakefulness
Respiratory effects: relaxation of bronchial smooth muscles; increased respiration and dilation of pulmonary arteries
CNS stimulants are potent drugs with a strong potential for tolerance and psychological dependence.
=> Classified as Schedule II under the Controlled Substance Act
NURSING RESPONSIBILITIES:
Should not be given in the evening or before bedtime because insomnia may result.
Monitor for tolerance and dependence
Monitor for drug abuse
Caffeine containing foods should be avoided
Food affects absorption rate
Instruct not to abruptly discontinue the drug to avoid withdrawal symptoms
2. Anorexiants- acts on cerebral cortex & on hypothalamus to suppress appetite
Mechanism of actions and drug effects
Suppress appetite control centers in the brain
Increase body’s basal metabolic rate: mobilization of adipose tissue stores and enhanced cellular glucose uptake and reduce dietary fat absorption
General Use:
used in the management of exogenous obesity as part of a regimen including a reduced caloric diet and exercise
Used in obese patients with a BMI of 30 or more; patients with BMI of 27 who are hypertensive or have high cholesterol or diabetes
Nursing Implications
Monitor weight and dietary intake prior to and periodically during therapy.
Advise patient that regular physical activity, approved by health care professional, should be used in conjunction with medication and diet.
3. Analeptics – acts on brainstem & medulla to stimulate respiratory center
Mode of action: Mostly stimulates the brainstem, spinal cord & cerebral cortex; inhibits the enzyme phosphodiesterase
Uses and Considerations: Used for newborns with apnea to stimulate respiration. Given through an NGT.
Nursing Implications
Assess blood pressure, pulse, respiration, lung sounds, and character of secretions before and throughout therapy.
History of cardiovascular problems should be monitored for ECG changes and chest pain.
Administer around the clock to maintain therapeutic plasma levels
CNS DEPRESSION
Drugs causing CNS depression are classified as: sedatives or hypnotics
- Sedatives reduce nervousness, excitability and irritability without causing sleep.
- Hypnotics cause sleep and have a much more potent effect on the CNS than sedatives
1.Sedative-Hypnotics
The mildest form of CNS depression is sedation
Diminishes physical and mental responses at lower dosages of certain CNS depressants (does not affect consciousness).
Increasing the drug dose can produce a hypnotic effect – not hypnosis but a form of “natural” sleep.
With very high doses of sedative-hypnotic drugs, anesthesia may be achieved.
There are short-acting hypnotics and intermediate-acting hypnotics: Short-acting hypnotics= useful in achieving sleep-> allow client to awaken early in the morning.
- Intermediate-acting hypnotics= useful for sustaining sleep
The ideal hypnotic promotes natural sleep without disrupting normal patterns of sleep and produces no hangover or undesirable effect.
Hypnotic drug therapy should be short term to prevent drug dependence and drug tolerance
Classified chemically into three main groups:
1. Barbiturates
Mechanism of Action and Drug Effects:
- acts primarily on the brainstem (reticular formation)
- hinders movement of impulses from the thalamus to the cerebral cortex creating depression in the CNS which can range from mild to severe
=> travel of impulses is inhibited due to its ability to potentiate GABA (primary inhibitory neurotransmitter of the brain)
Indications
All barbiturates have the same effect but differ in potency, time to onset of action and duration of action
Used as hypnotics, sedatives, anticonvulsants and anesthesia during surgical procedures
Therapeutic uses:
Ultrashort acting: anesthesia for short surgical procedures, anesthesia induction, control of convulsions, and reduction of ICP in neurosurgical patients
Short acting: sedation/sleep induction and control of convulsive conditions
Intermediate acting: sedation/sleep and control of convulsive conditions
Long acting: sleep induction, epileptic seizure prophylaxis
Nursing Implication:
* Because these drugs are taken approximately 1 hour for the onset of sleep, they are not prescribed for those who have trouble getting to sleep.
* Vital signs should be closely monitored in persons who take intermediate-acting barbiturates.
2. Benzodiazepines
Have anxiolytic & hypnotic dose related effects
More preferred than Barbiturates because:
1. prevents anxiety without causing much associated sedation.
2. less likely to cause dependence
Increased anxiety might be the cause of insomnia for some clients, so the following can be used to alleviate anxiety:
1. lorazepam (Ativan)
2. diazepam (Valium)
2. ANTICONVULSANTS; Also called antiepileptics
Goal: to suppress the rapid and excessive firing of neurons that start a seizure
*An excellent anticonvulsant would have few serious side effects. However, no such drug exists.
Action: Inhibit neuromuscular transmission
Uses: -
Long-term management of chronic epilepsy or recurrent seizures
Short-term management of acute isolated seizures not caused by epilepsy, such as after trauma or brain surgery.
Used in the emergency treatment of status epilepticus
Five Major Classes
Barbiturates
Benzodiazepines
Hydantoins
Iminostilbenes
Valproic acid
Assessment:
1. thorough patient history is necessary to identify the type of seizure disorder
2. Additional patient information: family history of seizures (if any) and recent drug therapy
3. other information needed: history of a head injury or a thorough medical history
4. Baseline vital signs data
5. Laboratory and diagnostic tests (EEG, CT scan, CBC, hepatic and renal tests)
6. On-going assessment:
6.1 May require frequent dose adjustments during the initial treatment period
6.2 Regular serum plasma levels of anticonvulsant are monitored for toxicity
6.3 Carefully document each seizure:
- time of occurrence
- length of the seizure
- psychic or motor activity occurring before, during, and after the seizure.
Analgesics are drugs that relieve pain without causing loss of consciousness. Although the proper analgesic may be extremely valuable in pain treatment, it is important to remember that complete masking of a pain symptom may not be desirable; masking can eliminate an important means of monitoring the progress of the underlying disease. Selection of the proper analgesic is generally based on six factors: effectiveness of the agent, duration of action, desired duration of therapy, ability to cause drug interactions, hypersensitivity of the client, and available routes of drug administration.
OPIOID ANALGESICS
Among the most potent analgesics now available are those derived from opium, a substance which is secreted from the unripe seed capsules of a species of poppy grown mostly in Turkey, India, China, and Iran. Opium has been used for thousands of years to alleviate pain and produce a sense of detachment and well-being (euphoria).
However, it was not until the sixteenth century that opium’s major component, morphine, was isolated. In the following years, many additional analgesics were naturally or synthetically derived from opium or were designed to mimic the pharmacological actions of opiate compounds. All of these agents became collectively known as the opioids or opioid analgesics.
Opioid analgesics, of which morphine is usually considered to be the prototype drug, exert a number of pharmacological actions. They are employed clinically primarily for their ability to produce analgesia. Opioids are primarily used in the treatment of moderate-to-severe pain originating from visceral sources (i.e., from the GI tract and other internal organs).
Morphine sulfate is the drug of choice for moderate-to-severe pain in children, such as postoperative pain. Some of these agents are also employed as cough suppressants and in suppressing the motility and secretion-forming ability of the gastrointestinal tract.
All of the narcotic analgesics are capable of causing dependence with regular use and are classified as controlled substances by the federal government.
Note: Do not administer opioid analgesics to clients with depressed respirations.
Severe respiratory depression that results from opioid use can be treated with naloxone (Narcan) given IV.
Instruct client to avoid activities requiring mental alertness.
Routinely evaluate the effectiveness of opioid analgesics in relieving pain.
Supportive nursing measures should be used to enhance the effectiveness of opioid analgesics (e.g., massage, positioning, emotional support, diversion, guided imagery).
Assess pain for type, location, and intensity before and 10–45 minutes after administration.
NONOPIOID ANALGESICS
Buprenorphine HCl (Buprenex), butorphanol tartrate (Stadol), nalbuphine hydrochloride (Nubain) and pentazocine hydrochloride (Talwin) were also developed to provide effective analgesic action without the abuse potential of the opioid analgesics. It has become evident that all of these agents exert some opioid antagonist activity. If they are administered to an opioid-dependent client, therefore, they may induce the development of withdrawal symptoms. Although none of these agents were initially believed to be capable of being abused, abuse of pentazocine has been frequently reported in recent years. As a result, this agent has been classified as a controlled substance by the federal government.
Note: Administer before pain becomes severe.
Assess client’s response to drug.
Be aware of possibility of dependency.
Supportive nursing measures (e.g., positioning, emotional support) should be used to enhance the effectiveness of these drugs.
early childhood socialization, and past experiences with pain. For example, older persons often tolerate chronic pain because they believe it is a natural occurrence in growing older. These factors must be taken into account when assessing pain.
KEY NURSING IMPLICATIONS:
1. Pain-relieving measures include positioning, massage, distraction, and use of analgesics.
2. Assess the onset, location, duration, intensity, and nature of pain, as well as other symptoms associated with the pain.
3. If the client is unable to provide information about pain, obtain information from the family and observe the patient for such signs of pain as anxiety, restlessness, and changes in vital signs.
4. Response to pain depends on the client’s developmental level, sex, ethnic group membership, early childhood socialization, and past experiences with pain.
5. Analgesics are most effective when given before pain becomes severe. 6. Do not undertreat pain because of a fear of producing drug addiction.
KEY NURSING IMPLICATIONS
Aspirin and Acetaminophen
1. Aspirin is contraindicated in persons taking anticoagulants, those with gastric ulcers, pregnant women, and children with febrile illness, such as flu.
2. Aspirin allergy must be noted on the client’s chart and medication record, and the client is instructed to avoid nonprescription drugs containing aspirin.
3. Use of aspirin in children has dramatically declined because of its most frequent use as an antipyretic, and it has been determined that aspirin should not be given with febrile illness caused by viruses.
4. Instruct the client to take sufficient fluid with aspirin to ensure that the tablets reach the stomach.
5. If gastrointestinal upset is experienced, aspirin can be taken with food or after meals. A readily soluble aspirin preparation should be used and a full glass of water should be taken with the aspirin. Also, an antacid may be taken or a buffered or enteric-coated product may be used.
6. Aspirin use may result in a false-positive reading for glycosuria. 7
. Tinnitus and vertigo may occur with high doses or continued use of aspirin. Reducing the dose will reverse these side effects.
8. Aspirin should be stored in closed, child resistant containers and kept out of the reach of children.
9. Overdoses with aspirin or acetaminophen must be treated promptly.
KEY NURSING IMPLICATIONS
Opioid Analgesics
1. Be proactive with pain control. Offer pain medication on a routine schedule when, in the nurse’s judgment, it is warranted.
2. Drug addiction does not occur frequently when opioids are used therapeutically.
3. Withdrawal symptoms can be prevented or treated by withdrawing the opioid slowly or by using methadone.
4. Assess all clients receiving opioids for respiratory depression. Do not administer opioid analgesics to clients with 12 or fewer respirations per minute. Notify the prescriber of respiratory depression.
5. Respiratory depression can be treated by the use of intravenous naloxone and other measures to support respiration.
6. Observe clients receiving opioids for hypotension, nausea, vomiting, and constipation.
7. To avoid constipation in clients receiving opioid analgesics, increase the client’s intake of fluid and dietary fiber, unless such measures are contraindicated by the client’s treatment plan.
KEY NURSING IMPLICATIONS
Opioid Drugs and the Law
1. All opioids are kept under double locks.
2. The use of all opioid drugs must be recorded on a special record and on the client’s record.
3. Lost or contaminated doses must be signed for by two nurses.
4. Opioids are counted by two nurses, one from the oncoming shift and one from the departing shift. Both nurses sign the record.
5. The nurse must be aware of the hospital policy for stop time on opioid orders.
NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDs)
The nonsteroidal anti-inflammatory drugs (NSAIDs) have emerged as the most important class of drugs used in the treatment of rheumatoid arthritis and related inflammatory disorders. These agents all exhibit varying degrees of analgesic and antipyretic effects and are believed to exert their anti-inflammatory effects by inhibiting the synthesis of prostaglandins. NSAIDs may be classified as salicylates or non-salicylates.
Note: Administration of these products with food, milk, or antacids will reduce the likelihood of gastrointestinal upset. Obtain history of allergic response to drugs. Assess client response to treatment. Keep these and other drugs away from children.
KEY NURSING IMPLICATIONS
Clients Receiving Nonsteroidal Anti-Inflammatory Agents
1. Acetaminophen cannot be substituted for aspirin in clients taking aspirin for its anti-inflammatory effects.
2. Ibuprofen, ketoprofen, calcium, and naproxen are not recommended for clients allergic to aspirin, those with hemophilia, or those taking anticoagulants.
3. Observe clients taking aspirin for allergic reactions, edema, excessive weight gain, constipation, gastrointestinal upset, tinnitus, and bleeding.
4. Indomethacin is ulcerogenic and can aggravate epilepsy and psychiatric disturbances. Clients allergic to aspirin should not take indomethacin.
5. Use of phenylbutazone may be associated with serious blood abnormalities. Report all evidence of sore throat, bleeding, mouth ulcers, or tarry stools immediately.
KEY NURSING IMPLICATIONS
Clients Receiving Corticosteroids
1. Systemic administration is associated with a broad range of side effects, including gastric ulceration, suppression of the hypothalamic-pituitary-adrenal system, hypertension, and changes in location of body fat deposits.
2. Clients receiving corticosteroids should be monitored for gastrointestinal bleeding and weight gain.
3. Both diabetics and nondiabetics should be monitored for blood glucose elevations while using corticosteroids.
4. Clients receiving intra-articular injections of these drugs must be cautioned not to overly stress the joint(s).
5. Teach clients on long-term therapy to carry identification and information about their treatment, to continue treatment, not to share medication, and to contact the physician whenever they are under unusual stress.
6. Impending adrenal crisis is indicated by hypotension, restlessness, weakness, lethargy, headache, dehydration, nausea, vomiting, and/or diarrhea.
7. Dietary modifications are specified, including sodium restriction and encouraging intake of calcium, because of a high risk for osteoporosis. Potassium supplementation may be indicated for clients taking corticosteroids.
8. Protect the client from infection and trauma and teach them measures to decrease risk.
9. Administer corticosteroids early in the day to avoid insomnia.
10. Provide instruction and support for the client being withdrawn from corticosteroids.
Self check 1.4
1. Explain common drug use as CNS stimulant and depression
2. Explain nursing responsibilities when administering CNS stimulant or depressionTopic 5:Major Drugs affecting major organ systems of the human body: Respiratory System
LEARNING OUTCOMES
1. Explain common drug use in respiratory system
2. Explain nursing consideration when administering medication involved respiratory system
ANTIHISTAMINES
Histamine is a naturally occurring substance in the body released in response to tissue damage and the presence of microorganisms and allergens invading body tissue. Histamine dilates arterioles to allow increasing blood supply to capillaries and the tissues supplied by capillaries. As a result of this flooding of tissues, they become red and large amounts of fluids leak into interstitial tissues.
The swelling is designed to prevent the microorganisms from traveling to other tissues and organs. This inflammatory response allows for leukocytes (white blood cells) to rush to the area to deactivate and absorb the microorganisms. Many of the discomforts associated with upper respiratory congestion and infections is a result of this swelling from the histamine release, including increased mucus production.
Another manifestation of histamine is itching common at the site of insect bites or other sources of contact inflammation (poison ivy, poison oak, etc.) Antihistamines do not affect the release of histamine, but act primarily to block the action of histamine at the H1 histamine receptor sites. They are, therefore, most useful in the treatment of allergic rhinitis. Their usefulness in the treatment of the common cold is controversial, because of the minimal contribution of histamine to the pathological state of the common cold. The action of antihistamines in the treatment of the common cold, however limited, is believed to be the result of the ability of these agents to exert a feeble anticholinergic action that reduces the amount of mucus secretion.
Antihistamines are capable of causing a wide variety of adverse effects. Many of these agents will produce varying degrees of sedation, particularly when used in combination with other depressant drugs or alcoholic beverages. Because of their chemical similarity to anticholinergic drugs, many antihistamines will cause dry mouth, constipation, blurred vision, and urinary retention. The effects are most prominent and troublesome in the elderly, particularly those with glaucoma or prostatic hypertrophy, as these conditions may be worsened by direct drug action.
The drying effect of antihistamines on the respiratory tract may thicken respiratory tract secretions and increase breathing difficulty in persons with respiratory disorders, such as asthma or emphysema. Antihistamine use is contraindicated in nursing mothers because they may inhibit lactation. Also, they can be secreted in breast milk and endanger a nursing infant. Young children may exhibit signs of hypersensitivity or over dosage to antihistamines
Note: These agents must be used with caution in clients with bronchial asthma, increased intraocular pressure, prostatic hypertrophy, and in the elderly. Their use with other CNS depressants (e.g., alcoholic beverages) may cause drowsiness and affect alertness. They may be administered with food or milk to reduce GI upset. Their administration should be discontinued at least 4 days prior to allergy skin testing since they may reduce the accuracy of the test.
DECONGESTANTS
Nasal decongestants are agents that constrict dilated blood vessels in the nasal mucosa by stimulating alpha1-adrenergic nerve receptors in vascular smooth muscle. This reduces the flow of blood in the edematous area, slows the formation of mucus, permits better drainage, and relieves the client’s discomfort.
Nasal decongestants are administered either topically, by inhalation, or orally. Topically used decongestants are effective and act rapidly. Duration of action varies from several minutes to several hours after a single application. A common problem in the use of these agents is rebounds nasal congestion. This occurs in clients who overuse topical decongestants. Excessive use causes local ischemia and irritation of the nasal mucosa that may lead to extensive secondary vasodilation and congestion.
Rebound congestion can generally be avoided by limiting the use of these agents to several days and by not exceeding recommended doses. Although topical administration of decongestants results in only minimal absorption of drug through the nasal mucosa, adverse systemic effects, such as elevation of blood pressure and CNS stimulation may occur if the decongestant solution drains through the nasal passage and is swallowed by the client.
Note: Oral decongestant drugs are contraindicated in clients with hypertension, heart disease, diabetes mellitus, or hyperthyroidism. Topical nasal decongestants must be used precisely as directed by the physician or the package instructions. Overuse may result in rebound nasal congestion. Clients should be instructed in the appropriate technique for administration of the product to be used. In infants and young children, topical decongestants should be administered about 20 minutes before meals, so that nasal passages will be clear for breathing during sucking or eating. Monitor clients using oral or topical decongestants for development of headaches, insomnia, nervousness, or cardiac palpitations. Avoid the use of these agents in clients receiving monoamine oxidase (MAO) inhibitors
EXPECTORANTS
Expectorants are agents administered orally to stimulate the flow of secretions in the respiratory tract. In doing so, the viscosity of endobronchial secretions and accumulated phlegm is reduced and removal by coughing and ciliary action is facilitated. Greater secretory activity in the respiratory tract also aids in the hydration of dry, irritated tissue and provides a soothing coating to protect against further trauma. There is considerable controversy regarding the therapeutic efficacy of expectorants. This stems from the absence of reliable data to substantiate the reduction of sputum viscosity by expectorants as compared to a placebo.
Expectorants continue to be used, however, on the basis of subjective evidence that they have a useful therapeutic effect. Guaifenesin is the most popular expectorant in current use and is an ingredient in many commercial cough preparations. Guaifenesin is well tolerated by most clients and can be formulated into a palatable syrup. It may cause stomach upset or nausea on rare occasions, because of its stimulatory effect on the production of gastric secretions.
Note: Clients taking expectorants should be taught to cough effectively. This includes sitting in an upright position and taking several slow, deep breaths before coughing. Secretions must be disposed of properly. Sufficient humidification must be added to the air. Encourage fluid intake to help liquefy secretions. May be used with percussion and vibration to help eliminate secretions
ANTITUSSIVES
A cough is a physiological mechanism useful in removing foreign material and excessive secretions from the respiratory tract. A cough may be productive or nonproductive, i.e., it may or may not result in the removal of excess respiratory secretions. Involuntary cough should not, therefore, be suppressed unless it causes respiratory discomfort or sleep disturbance, or if the cough does not facilitate removal of excess secretions from the respiratory tract. Both narcotic and nonnarcotic cough suppressants are available. The narcotic agents particularly codeine and hydrocodone, are considered to be the most effective and are reasonably safe to use for most clients. They act in suppressing the cough reflex by a direct depressant effect on the cough center in the medulla of the brain.
Note: Teach client to cough effectively. This includes sitting in an upright position and taking several slow deep breaths before coughing. Secretions must be disposed of properly. Encourage fluid intake. Do not give water after administration of cough syrups. Cough should not be suppressed, when it is productive or beneficial; for example, after surgery (with support). Assess the frequency and nature of cough, as well as the nature of secretions produced. May be used with percussion and vibration to help eliminate secretions.
KEY NURSING IMPLICATIONS
Expectorants and Antitussives
1. Persons with a cough lasting more than 1 week and those with high fever, rash, or persistent headache should be referred to a physician.
2. Assess the nature, duration, frequency, and productivity of cough.
3. Cough syrups given for their local soothing effect should not be followed immediately by food or water.
4. Teach clients about environmental modifications that may decrease cough and/or aid in expectoration of respiratory secretions.
5. Productive coughs should not be suppressed. Clients should be instructed in how to cough productively.
6. Sufficient fluid intake is beneficial in aiding the expectoration of respiratory secretions.
7. Saturated solution of potassium iodide (SSKI) is measured in drops and can be mixed in fruit juices or beverages to disguise its taste. Do not administer this drug to clients allergic to iodine.
8. Teach the client about disposing of secretions properly and preventing respiratory infections.
9. As with all medications, these should be kept out of the reach of children. Syrup of ipecac and the number of the local poison control center should be available if a child accidently ingests an overdose.
Bronchodilation can often make the difference between comfort and discomfort or even life and death of a client with an obstructive pulmonary disease. To understand how these drugs work, it is useful to review the processes involved in bronchoconstriction and bronchodilation. When an antigen is introduced into the body of an atopic individual, the antigen combines with a mast cell to form a sensitized mast cell. When this cell is re-exposed to the antigen, it responds with the formation and release of a number of chemical substances, including histamine and leukotrienes. Such chemical substances act either directly to cause bronchoconstriction or indirectly to stimulate the release of acetylcholine, which may cause smooth muscle contraction.
Sympathomimetic Agents Within the mast cell are specialized adrenergic receptors—known as beta2 receptors—which control bronchial smooth muscle tone. When these are stimulated by certain sympathomimetic agents, such as albuterol, bitolterol, epinephrine, ethylnorepinephrine, ephedrine, isoetharine, isoproterenol, metaproterenol, pirbuterol, salmeterol or terbutaline, there is an increase in the formation of cyclic adenosine monophosphate (AMP). This is associated with smooth muscle relaxation and bronchodilation. When these receptors are blocked by a drug such as propranolol (Inderal), bronchoconstriction takes place. This is why beta-adrenergic blocking agents such as propranolol are contraindicated in clients with COPD. Because some of the drugs that stimulate beta2 receptors also stimulate beta1 receptors located in the heart, many of these drugs may be dangerous to use in a client with COPD who also suffers from heart disease. Some of the newer drugs that have been introduced (e.g., albuterol, bitolterol, isoetharine, metaproterenol, pirbuterol, salmeterol, and terbutaline) exert a more selective action on beta2 receptors and do not pose as significant a threat to a client with heart disease.
Note: Client education is very important and must include instruction in ways to decrease environmental irritants, improve humidification of air, and use medication properly, including inhalers. Multiple inhalation medications should not be used, unless ordered by the physician. The client is advised to use the inhaler at the first sign of distress or tightness of the chest and to routinely wash, dry, and replace the mouthpiece. Monitor changes in cardiac function and blood pressure, especially in the elderly.
MUCOLYTICS
Mucolytics reduce the thickness and the stickiness of pulmonary secretions, so that removal by ciliary action and cough is facilitated and pulmonary ventilation can be improved. They are used in the treatment of obstructive pulmonary diseases, such as chronic bronchitis and emphysema, as well as in other diseases, such as cystic fibrosis and pneumonia, in which purulent or non-purulent respiratory blockage may be present. The most commonly used mucolytic agent is acetylcysteine (Mucomyst). The action of this drug is attributed to its ability to break chemical bonds responsible for the high viscosity of mucus.
KEY NURSING IMPLICATIONS
Bronchodilators and Other Respiratory Drugs
1. Assessment focuses on signs and symptoms of respiratory distress, adequacy of gas exchange, and activity tolerance.
2. Clients should be instructed in medication administration procedures (use of an oral inhaler, extender device, and Medi-Mist device) and care of equipment.
3. Mucolytic agents usually have an unpleasant taste, and mouth care should be provided frequently.
4. Bronchodilators may cause tachycardia, cardiac arrhythmias, and gastrointestinal symptoms. Monitor the client carefully.
5. Bronchodilators with central nervous system stimulating effects may cause insomnia. Provide appropriate comfort measures.
6. Bronchodilators such as theophylline, which are irritating to the gastrointestinal tract, should be given with food or milk.
7. Teach clients with COPD to control breathing, to avoid respiratory infections, and to modify their environment to decrease bronchial irritants.
8. Do not wear perfume or colognes when working with clients, especially those with respiratory conditions.
9. Do not use talc or bath powder around these clients.
Self Check 1.5
1. Explain common drug use in respiratory system
2. Explain the nursing responsibility when administering the drug related.Topic 6 : Major Drugs affecting major organ systems of the human body: Cardiovascular System
LEARNING OUTCOMES
1. Explain the common drug use in Cardiovascular System.
2. Explain nursing consideration when administering drug in Cardiovascular system.
Cardiac Stimulants and Depressants
The heart is a complex blood-pumping organ which contains specialized cardiac muscle and a unique system for generating and conducting electrical impulses. The most powerful generator of electrical impulses in the heart is the sinoatrial (SA) node (Figure 28–1). When the SA node generates an electrical impulse, a contraction of the atrium occurs. The impulse then proceeds through the atria to the atrioventricular (AV) node, which usually acts to coordinate atrial and ventricular contraction. However, the atrioventricular node can act as a pacemaker when the generator of impulses from the SA node is suppressed. Rhythms generated by the SA node are referred to as sinus rhythms. Those emanating from the AV node are called nodal rhythms. Electrical activity through the SA and AV nodes is dependent, to a great extent, on the influx of calcium through channels in the cardiac cell membrane into the cell. The entire contraction of the heart is known as a systole. Although both the atria and the ventricles have systole and diastole periods (the atria in systole when the ventricles are in diastole and the atria in diastole when the ventricles are in systole), the systole in the ventricles is considered the heartbeat, because it is audible and palpable. Systole occurs about 60–100 times each minute in adults and more rapidly in children and infants, depending on their age. For example, infants have a normal heart rate of 120–160 beats per minute, with the normal rate for toddlers being 90–140 beats, for preschoolers 80–110 beats, school-age children 75–100 beats, and adolescents 60–90 beats. Each systole is normally followed by a period of cardiac muscle relaxation known as diastole.
Heart rate is primarily controlled by the autonomic nervous system (ANS). Parasympathetic (cholinergic) nerve endings (vagal fibers) are located in close proximity to the SA node and other areas of the atria and ventricles. With stimulation of these nerves (vagal stimulation), the neurotransmitter acetylcholine is released at the junction of the nerve and the cardiac muscle (myocardium). This acts to slow the heart rate by inhibiting impulse formation and electrical conduction in the heart. Sympathetic (adrenergic) nerve fibers also innervate various portions of the heart. When these are stimulated, the neurotransmitter norepinephrine is released. This action tends to increase heart rate by promoting impulse formation and electrical conduction in the heart. Sympathetic stimulation also tends to reduce the time interval between consecutive generations of impulses. It therefore reduces the duration of the refractory period, i.e., the time between consecutive muscle contractions. Drugs can change several aspects of cardiac action. They can: increase or decrease the force of myocardial contraction. Drugs that increase the force of contraction are said to exert a positive inotropic effect on the heart. Those that reduce the force of contraction are said to exert a negative inotropic effect. increase or decrease heart rate by altering the rate of impulse formation at the SA node. Drugs that increase heart rate are said to exert a positive chronotropic effect. Those slowing heart rate are said to exert a negative chronotropic effect. increase or decrease the conduction of electrical impulses through the myocardium. Drugs that increase the rate of electrical conduction are said to exert a positive dromotropic effect. Those that slow conduction is said to exert a negative dromotropic effect
CARDIAC GLYCOSIDES
Digoxin and similar drugs belong to a chemical class usually referred to as the cardiac glycosides. They are all derived from natural sources and have been recognized for centuries for their medicinal qualities. Although commonly employed in ancient civilizations as emetics, diuretics, heart tonics, and even as rat poisons, the cardiac glycosides have emerged during the last century as popular and effective agents for the treatment of congestive heart failure.
This condition is often the result of the sustained presence of one or more underlying cardiovascular diseases in the client. Congestive heart failure is often characterized by: cardiac distention resulting from the inability of the ventricles to pump the entire volume of blood with which they are presented cardiac hypertrophy caused by the heart’s adaptation to prolonged stretching sodium and water retention caused, in part, by diminished renal blood flow These effects result in weight gain, edema, shortness of breath, pulmonary congestion, and a variety of other symptoms.
Cardiac glycosides usually provide effective treatment for congestive heart failure by exerting a positive inotropic action on the heart. In so doing, they increase the force of myocardial contraction and thereby improve the mechanical efficiency of the heart as a blood-pumping organ. This ultimately results in a reduction in heart size and increased blood flow to the kidneys. Improved renal blood flow causes a diuretic effect, which eventually reduces the concentration of sodium and water in the body. Cardiac glycosides also tend to exert negative chronotropic and dromotropic actions on the heart, thereby making them potentially useful agents in the treatment of various cardiac arrhythmias.
Note: Taking digitoxin or digoxin with meals may decrease gastric irritation.
Do not administer if pulse is less than 60 beats per minute (adults), 90 beats per minute (infants), or 70 beats per minute (children up to adolescence).
Report heart rates below these levels to the physician. Also report heart rates of 100 or more per minute.
Report any evidence of irregular rhythm.
Observe client for toxicity, including symptoms of headaches, visual disturbances, nausea, vomiting, anorexia, or disorientation.
Clients taking diuretics other than potassium-sparing diuretics are at particular risk of developing toxicity.
Monitor potassium levels and encourage intake of potassium-rich foods. Client education is especially important.
This includes instruction in taking a radial pulse, as well as directions to notify the physician if indications of toxicity occur.
Hypothyroid clients are particularly sensitive to these drugs.
Monitor drug level.
ANTIARRHYTHMIC AGENTS
Although the rhythm of the heart is generally controlled by its principal pacemaker, the SA node, spontaneous electrical discharge or automaticity may occur anywhere in the heart under certain conditions. Any electrical activity initiated by such a spontaneous discharge is considered to be a rhythm disturbance, or arrhythmia
Antiarrhythmic drugs act to diminish or obliterate rhythm disturbances by: decreasing the automaticity of cardiac tissues distant from the SA node (i.e., at ectopic sites) altering the rate of conduction of electrical impulses through the heart altering the refractory period of cardiac muscle between consecutive contractions The selection of the most appropriate antiarrhythmic agent is dependent on the type of arrhythmia treated, the presence of other pathological conditions (e.g., heart failure, pulmonary disease), the relative safety of the drug as compared to other means of therapy, and the onset and/or duration of action of the drug. Most antiarrhythmic agents are administered intravenously (inamrinone lactate, milrinone lactate, digoxin, adenosine, diltiazem HCl, and others) until the heart has converted to normal sinus rhythm (NSR). Oral doses are used to maintain NSR
CARDIAC STIMULANTS USED TO TREAT SHOCK
Adrenergic or sympathomimetic drugs are agents that mimic the action of the neurotransmitter norepinephrine. They may act to cause: vasoconstriction of peripheral blood vessels vasodilation of blood vessels in skeletal muscle increased heart rate (positive chronotropic effect) increase in the force of contraction of the heart (positive inotropic effect) increased rate of glycogenolysis in the liver and skeletal muscle stimulation of the CNS Not all sympathomimetic agents will produce each of these effects to the same degree. Their action is often dependent on their degree of selectivity for specific adrenergic receptors in the body. Some sympathomimetic agents have a selective action on alpha-adrenergic receptor sites
Note: Monitor the apical pulse for 1 minute before administration.
Record rate and rhythm of heartbeat.
Patient should be supine when IV doses are administered to prevent postural hypotension.
Sympathomimetic Agents Used in the Treatment of Shock
Note: An intravascular line is usually established so that these drugs can be given by IV. During emergency treatment the nurse must keep track of the names and dosages of drugs administered.
Monitor client’s vital signs and condition continuously when drugs are given IV.
Record intake and output on all clients. Infiltration may result in tissue necrosis.
NURSING IMPLICATIONS
Cardiac Glycosides
1. Always check the client’s apical pulse rate for 1 minute before administering these products.
2. Withhold these drugs if the pulse rate is less than 60 beats per minute in adults, less than 90 beats per minute in infants, and less than 70 beats per minute in children and adolescents.
3. Report bigeminy (if on monitoring) or significant deviations in the client’s heart rate or rhythm.
4. Assess the client for toxicity by checking the heart rate and rhythm and observing for neurological signs, such as headache, visual disturbances and changes in color vision and gastrointestinal symptoms such as nausea, vomiting and anorexia.
5. Monitor potassium level and report level less than 4 ml.
6. To minimize pain and possible tissue damage, intramuscular preparations must be given deep into a large muscle mass.
7. Teach the client and family members how to recognize signs of toxicity and assess heart rate.
Antiarrhythmic Agents
1. Assess the client’s apical pulse for 1 minute before administration.
2. Clients scheduled to receive lidocaine, tocainide, or procainamide should be questioned about allergy to local anesthetics.
3. Give quinidine at mealtimes to decrease gastrointestinal upset.
4. The client should always be supine when intravenous quinidine is administered.
5. Clients receiving intravenous lidocaine or procainamide should be supine during administration.
6. Check vital signs on all clients following intravenous administration of antiarrhythmic drugs. Report signs of confusion or convulsions in clients following lidocaine or procainamide use.
7. Report evidence of granular deposits on the cornea of clients taking amiodarone.
8. Verapamil HCl may cause hypotension and disturbances of cardiac rhythm. Stop intravenous administration if the systolic blood pressure drops below 70–80 mm/Hg and if the pulse drops below 50 beats per minute.
Coronary Vasodilators
1. Assessment focuses on determining the frequency, nature, and precipitants of anginal attacks and the effectiveness of vasodilators in relieving angina.
2. Sublingual or lingual nitroglycerin should be used at the first sign of an attack of angina.
3. Clients using nitroglycerin products, such as sublingual tablets, lingual spray, or ointment, plus those using amyl nitrite are advised to sit or lie down before using the product, as hypotension is possible. Alcohol may intensify hypotensive effects.
4. A fresh supply of sublingual nitroglycerin tablets should be obtained every 3 months. Avoid storage in areas subjected to prolonged heat.
5. Nurses must avoid direct contact with topical preparations of nitroglycerin. Review the procedure for applying nitroglycerin ointment and the guidelines for use of a transdermal nitroglycerin system.
6. Intravenous nitroglycerin must only be administered using glass bottles and special administration sets. Do not mix other drugs with the nitroglycerin.
7. When both a beta-adrenergic blocking agent and a vasodilator are ordered, schedule administration of the blocking agent first.
8. Calcium channel blockers should be taken with meals or milk. Blood pressure should be routinely monitored.
Peripheral Vasodilators
1. Assessment includes inspection of the skin, auscultation, palpation, and interviewing.
2. Clients experiencing light headedness or dizziness when taking vasodilators should be advised to lie down until these side effects pass.
3. A flushed or warm feeling often results from the use of vasodilators and is not a cause for alarm.
4. Clients with peripheral vascular illnesses require an education program focused on general hygiene and safety.
ANTICOAGULANTS
These drugs inhibit the action or formation of one or more clotting factors. None, however, is capable of exerting a fibrinolytic effect on existing clots.
Heparin is an agent found in mast cells located throughout the body. It has been found to be a potent inhibitor of the clotting process and has been used for more than 40 years in the prophylaxis and treatment of clotting disorders related to coronary occlusion, cerebral thrombosis, cerebral vascular accidents (CVAs), and many other diseases. Heparin indirectly interferes with the conversion of prothrombin to thrombin
Note:
These agents should be used with caution in clients with trauma, infection, hypertension, diabetes, or major surgery.
Prothrombin times should be taken every 4 to 6 weeks once the client has been stabilized. Monitor the client for the development of drug interactions.
KEY NURSING IMPLICATIONS
Anticoagulants
1. Report abnormal bleeding or indications of internal bleeding, such as headache, tarry stools, and changes in neurological status.
2. To avoid intramuscular injection of heparin, select a short needle and choose a site with adequate subcutaneous tissue.
3. The effects of heparin can be reversed through the intravenous use of protamine sulfate.
4. When heparin is administered by continuous intravenous infusion, an infusion pump is generally used to ensure a precise rate of infusion.
5. When administering heparin through a saline lock, disinfect the diaphragm, use a small-gauge needle and watch for signs of infiltration.
6. Contact the prescriber before administering the next dose of an oral anticoagulant if the prothrombin time is 30 seconds or greater.
7. Review the procedure for safe administration of heparin.
8. Monitor partial thromboplastin time (PTT) when administering heparin and contact the prescriber if PTT is not within prescribed parameters (usually 1.5–2.5 times normal [30–40 seconds]).
Comfort and Safety During Anticoagulant Therapy
1. Avoid intramuscular injections in clients on anticoagulants. If such injections are necessary, maintain pressure on the site for several minutes after injection.
2. Vitamin K1 (phytonadione) is used as an antidote for oral anticoagulants.
3. Avoid the use of aspirin and aspirin containing products
Anticoagulants
1. Clients are advised to avoid situations that could lead to trauma.
2. Clients are instructed to talk with the primary care provider before adding or subtracting any drug from their treatment program.
3. Drastic changes in diet, laxatives and mineral oil should be avoided.
4. Identification and information about treatment should always be carried or a Medic-Alert tag worn.
5. Women on anticoagulants who are considering pregnancy must be referred to an obstetrician.
Thrombolytic Agents
1. Observe the client receiving streptokinase for allergic reactions. Observe all clients receiving thrombolytic agents for bleeding, changes in vital signs, and chest pain.
2. Reconstitute streptokinase with Sodium Chloride Injection or Dextrose (5%) Injection. Do not shake the vial to mix it.
3. Many clients develop reperfusion arrhythmias that require prompt identification and treatment following alteplase use.
4. To minimize bleeding, intravenous lines are established prior to initiating therapy with thrombolytic agents.
5. Apply manual pressure for 20 to 30 minutes, followed by application of a pressure dressing on all puncture sites during and following thrombolytic therapy.
6. Use preservative-free sterile water for injection to reconstitute alteplase.
7. Following the infusion of alteplase, the line is flushed with 5% Dextrose in water (D5W) or normal saline, to ensure administration of the entire dose.
8. Institute safety measures (e.g., padded siderails, routine vital signs, assessment of skin) to prevent unnecessary blood loss.
9. Monitor the client for the development of re occlusion of the coronary arteries.
10. Client and family education regarding drug therapy and lifestyle changes is an important nursing function.
Self check
1. Explain nursing responsibility when administering cardiac drugs.Topic 7 : Major Drugs affecting major organ systems of the human body: Renal System
LEARNING OUTCOMES
After studying this chapter, the student will be able to:
1. List the major health problems for which treatment with diuretic drugs is used
2. List the major classes of diuretics, their mechanism of action and their side effects
DIURETICS
Drugs used to remove sodium and water from the body. They are clinically employed in clients with edema or ascites, both of which are pathological increases in extracellular fluid volume. Diuretics are also used in the treatment of hypertension, as they can promote blood pressure reduction while reducing the adverse effects of other antihypertensive drugs.
DIURETICS AND ANTIHYPERTENSIVES
on the concentration of the hormone, aldosterone. The regulation of sodium balance by the kidney is therefore determined by: glomerular filtration rate (i.e., the rate at which fluid is filtered by the kidney glomeruli) concentration of aldosterone, a hormone secreted by the adrenal cortex baroreceptors of the body In certain illnesses the excretion of sodium may be impaired, thus leading to the accumulation of fluid and sodium within the body. Diuretics are designed to correct this situation by promoting the excretion of sodium by inhibiting its reabsorption.
Thiazide Diuretics
The thiazide diuretics were developed in the 1950s and have evolved to be the safest diuretic agents in current use. They appear to act by inhibiting sodium and chloride reabsorption in the early portion of the distal tubule, although they may also block chloride reabsorption in the ascending hoop of Henle. As the concentration of sodium reaching the distal tubule is higher in clients using thiazide diuretics, a greater than normal sodium-potassium exchange takes place, thereby possibly leading to potassium depletion and hypokalemia. Because of the neurotransmission importance of potassium, its depletion can have serious, even life-threatening, consequences. Neurotransmitters conduct impulses to muscles of the body including and most particularly the heart. Thus, with insufficient potassium, clients may experience cardiac arrhythmias, as well as muscle weakness in skeletal and smooth muscles of the body. In addition, an excessive amount of chloride is also sometimes excreted by such clients, thereby leading to chloride depletion and metabolic alkalosis.
Note:
These drugs may cause hyperuricemia and hyperglycemia.
Carefully monitor clients with gout or diabetes mellitus.
Monitor potassium level and assess client for hypokalemia, including symptoms of muscle cramps and weakness.
Encourage intake of potassium-rich foods, including citrus fruits, bananas, and apricots.
Give drug early in the day to prevent nocturia.
Record intake and output on hospitalized clients.
Monitor blood pressure and weight.
Observe clients taking thiazide diuretics with cardiac glycosides for the development of cardiac glycoside toxicity (visual disorders, bradycardia, bigeminy, nausea, vomiting, and anorexia).
Use of alcohol, barbiturates or narcotics may aggravate postural hypotension.
Discontinue drug use before parathyroid function tests are performed.
Loop Diuretics
Loop diuretics, furosemide (Lasix), ethacrynic acid (Edecrin), bumetanide (Bumex), and torsemide (Demadex) are widely used. These agents act by inhibiting the reabsorption of sodium and chloride in the ascending loop of Henle, thereby reducing the ability of the kidneys to concentrate urine. The loop diuretics are considerably more potent than the thiazides in promoting sodium and fluid excretion. Unlike the thiazides, they remain effective, even in clients with seriously impaired glomerular filtration rates. This has made them popular agents in treating elderly clients, who may not adequately respond to thiazides. Because of the relatively high concentration of sodium that enters the distal tubule, considerable sodium-potassium exchange occurs in clients using loop diuretics, thereby promoting the development of hypokalemia. The use of these agents has also been associated with hearing loss, particularly when administered parenterally in high doses.
Potassium-Sparing Diuretics
Several agents having diuretic activity, but different modes of action, exert their action in the distal tubule. Spironolactone (Aldactone) imparts its diuretic activity by inhibiting the action of the hormone aldosterone. Triamterene (Dyrenium) and amiloride HCl (Midamor) directly block sodium reabsorption in the distal tubule independently of aldosterone. None of these agents is a potent diuretic.
Osmotic Diuretics
Osmotic diuretics are agents capable of being filtered by the glomerulus, but have a limited capability of being reabsorbed into the bloodstream. This results in a high concentration of osmotic agent in the kidney tubule, which leads to large amounts of fluid and produces a profound diuretic effect. Agents such as glycerin and isosorbide are used orally. Urea and mannitol are administered intravenously as osmotic diuretics. They are employed primarily in the treatment of increased intracranial pressure, but is also used to treat acute renal failure as well as in conditions where rapid reduction of the pressure and volume of intraocular and/or intraspinal fluid is required.
Carbonic Anhydrase Inhibitors
Carbonic anhydrase is an enzyme found in a number of organs of the body, including kidneys and eyes. In kidneys, the enzyme acts to promote the reabsorption of sodium and bicarbonate from the proximal tubule, thereby maintaining the alkalinity of the blood. The administration of drugs such as acetazolamide (Diamox), dichlorphenamide (Daranide), and methazolamide (Neptazane) that inhibit carbonic anhydrase activity, promotes the excretion of bicarbonate, sodium and water, and results in a mild diuretic effect.
The use of carbonic anhydrase inhibitors as diuretics has diminished greatly with the development of more effective diuretic drugs. These agents are used widely, however, for the reduction of intraocular pressure in glaucoma clients (review Chapter 26). This application is based upon the observation that inhibition of carbonic anhydrase activity reduces the rate of production of aqueous humor in the eye.
Non-thiazide Diuretics
Note:
Give early in the day to prevent nocturia.
Record intake and output in hospitalized clients.
Monitor fluid and electrolyte balance, especially potassium.
Observe clients taking cardiac glycosides and diuretics, other than potassium-sparing diuretics, for the development of cardiac glycoside toxicity (visual disturbances, bradycardia, bigeminy, nausea, vomiting, and anorexia).
Monitor blood pressure and weight.
Diuretics
Oral diuretics have long been considered to be the cornerstone of antihypertensive drug therapy and are often used as the initial form of treatment. Most of these agents have been shown to be capable of lowering both systolic and diastolic blood pressure in virtually all clients treated for essential hypertension. They will also potentiate the action of most other oral, nondiuretic, antihypertensive agents.
Nondiuretic Antihypertensive Agents
Note:
Client education program should stress the importance of compliance.
Monitor blood pressure. If postural hypotension occurs, teach client to change position slowly, especially on first rising in the morning. Elastic stockings or ingesting a high-protein snack at bedtime may also be helpful.
Clients on sodium-restricted diets require special instruction and follow-up.
Assessment
1. In measuring blood pressure, use an appropriate size cuff.
2. If a reading of 140/90 or higher is obtained, check the blood pressure in the other arm, take a personal, family, and medication history and observe the client’s level of anxiety.
3. Refer clients to the physician if they have three elevated readings 1 week apart.
4. Ongoing assessment includes blood pressure readings, weight, inquiries about diet, alcohol intake, exercise, smoking, and problems related to medication
Sodium and Potassium Needs
1. Some clients with hypertension benefit from a sodium restricted diet, either mild (1,500–2,000 mg), moderate (1,000 mg) or severe (500 mg).
2. Clients on sodium-restricted diets may experience sodium deficit, particularly during hot weather. A temporary increase in sodium is recommended.
3. Muscle cramps, muscle weakness, and change in the pulse may indicate potassium deficit. Potassium is replaced by intake of foods such as fruits and fruit juices.
4. Clients on sodium-restricted diets must be taught to read the labels on foods and medications to identify sources of sodium.
5. Clients taking potassium-sparing diuretics are instructed to avoid salt substitutes containing potassium.
Limiting Adverse Effects
1. Cooperation may be enhanced when the unpleasant side effects of therapy are controlled.
2. Assess blood pressure, weight, tissue turgor, and indications of low serum potassium such as muscle weakness, leg cramps and pulse irregularities.
3. Maintain intake and output records for all hospitalized clients taking diuretics.
4. Use of thiazide diuretics may result in hyperglycemia, with both thiazides and ethacrynic acid possibly increasing serum uric acid levels. Diabetics and those with gout must be monitored carefully.
5. Rauwolfia derivatives may produce nasal stuffiness and mental depression. Clients are advised to avoid the use of over-the counter decongestants containing pressor agents. Therapy may be discontinued if the client becomes depressed.
6. Postural hypotension is alleviated by changing positions slowly, eating a high protein snack at night, flexing the calf muscles to increase blood return to the heart and wearing elastic stockings or a counter-pressure garment. Clients are cautioned to avoid alcohol and straining at stool and to hold onto a stationary object when rising.
7. Observe clients taking beta-adrenergic blocking agents for respiratory difficulties and bradycardia. Diabetics are monitored for hypoglycemia. All clients are instructed to protect the extremities from cold.
8. Clients taking antihypertensives should tell other health care personnel that they are taking these drugs.
9. Observe the elderly for orthostatic hypotension and protect them from falls.
Long-Term Client Management
1. Clients are advised to avoid heavy meals and exercise after meals.
2. Straining at stool is contraindicated, and measures should be taken to prevent constipation.
3. Weight loss is recommended, and clients who smoke should be encouraged to quit.
4. Aerobic exercise, avoidance of alcohol, and a diet rich in potassium and calcium may all be important in controlling blood pressure.
5. Clients should learn coping measures to deal with stress.
6. Clients are instructed to read the labels of over-the-counter (OTC) drugs since many of them contain pressor substances contraindicated in hypertension
Hypertensive Emergencies
1. A hypertensive emergency exists when the diastolic blood pressure exceeds 120 mm Hg and there is evidence of end organ damage.
2. Medications, such as sodium nitroprusside or diazoxide, will be administered intravenously.
3. Monitor the vital and neurologic signs and report significant changes.
Topic 8 : Major Drugs affecting major organ systems of the human body: Digestive System
LEARNING OUTCOMES
After studying this chapter, the student will be able to:
1. Explain the difference between systemic and non-systemic antacids and give
an example of each
2. Describe three ways that antacids may interact with other drugs
3. Apply the nursing process related to caring for clients receiving antacid therapy
Antacids are alkaline chemical agents used for relief of symptoms associated with hyperacidity and peptic ulcer disease (PUD). There is considerable controversy as to the function of antacids in treating these common gastrointestinal disorders. Although it has long been established that antacids reduce the corrosiveness of gastric acid and decrease
pepsin activity, there is little conclusive evidence to support the contention that antacids enhance the healing, decrease the frequency, or prevent the recurrence of peptic ulcers.
The primary goal of antacid therapy is the relief of pain. The pain-reducing effect of antacids is believed to be due to their:
acid neutralizing capacity inhibition of the protein-digesting ability of pepsin
action to increase the resistance of the stomach lining to irritation
ability to increase the tone of the lower esophageal sphincter
This latter action is believed to explain why antacids are effective in reducing pain associated
with gastroesophageal reflux (GER).
Selection of the proper antacid is important because most clients on antacid therapy will be
using large doses for a prolonged time. An ideal antacid product:
effectively neutralizes large volumes of acid with a reasonably small dose.
avoids causing “acid rebound.” This is a phenomenon characterized by the production of
greater than normal volumes of acid by the stomach when the pH of its contents is raised
above the desirable 4–5 range. Above this level, the stomach responds to alkalinization
by secreting more acid, thereby returning the client to a state of hyperchlorhydria.
has a prolonged action. It should provide prompt relief and then continue to provide relief for several hours. This is an important feature, as the client may not take the medication as directed if the antacid must be administered too frequently. In other words, client cooperation is more likely if relief continues for some time after the antacid is taken.
does not interfere with the digestion or absorption of nutrients or drugs. Many antacids
form chemical complexes with drugs such as the tetracycline antibiotics. When these drugs
form complexes, the tetracycline is not absorbed well from the gastrointestinal tract
and is not as effective. Antacids should, therefore, not be administered within 2 hours of
an oral dose of a tetracycline. Antacids have also been found to adsorb certain drugs onto
their surface—that is, the drug sticks to the surface of the antacid particles. Some
antacids may slow or impair the absorption of digoxin.
Active Ingredients in Antacid Products
ü Administration with other drugs or food may reduce the absorption of these agents.
ü Do not take other oral drugs within 1–2 hours of antacid administration.
ü Monitor quality and consistency of stool during antacid therapy.
ü Shake liquid antacid products well prior to use.
ü Follow administration of antacid with a small amount of water or milk to facilitate passage into stomach.
ü Do not administer within 1–2 hours of any enteric-coated drug product.
ü Assess the client’s response to antacid use
KEY NURSING IMPLICATIONS
Antacids
1. Maintain a schedule for antacid administration. Antacids should be administered
following meals or a snack.
2. Shake all liquid preparations thoroughly and instruct clients to chew tablets well
and to follow the tablets with water.
3. Avoid the use of aspirin, ibuprofen and naproxen in clients with peptic ulcer disease.
4. Discuss the development of diarrhea or constipation with the prescriber.
5. Avoid simultaneous administration of antacids and antibiotics
Antispasmodics that Are Belladonna Derivatives
ü Administration is contraindicated in clients with narrow-angle glaucoma, renal disease, prostatic hypertrophy, obstructive disease of the GI tract, or preoperatively for open heart surgery.
ü May reduce tolerance to high environmental temperature.
ü Administer 30–60 minutes before meals and at bedtime.
ü Gum, hard candy, or ice chips may be provided to relieve dry mouth.
ü Monitor client for development of constipation, reduced urinary output, skin rash, flushing, or eye pain.
ü Elderly clients may develop excitement, confusion, agitation, or drowsiness.
ü Diminished doses should be used in the elderly.
ü Neostigmine methylsulfate (0.5–2 mg) may be given intravenously to treat overdose. Physostigmine (1–4 mg)
ü administered by slow IV injection also has been successfully used to reverse anticholinergic effects.
ü Assess client for therapeutic effectiveness.
Synthetic Anticholinergics Used as Antispasmodics
ü Administration is contraindicated in clients with narrow-angle glaucoma, renal disease, prostatic hypertrophy, obstructive disease of the GI tract, or preoperatively for open-heart surgery.
ü May reduce tolerance to high environmental temperature (impairs ability to perspire).
ü Administer 30–60 minutes before meals and at bedtime.
ü Gum, hard candy, or ice chips may be provided to relieve dry mouth.
ü Monitor client for development of constipation, reduced urinary output, skin rash, flushing, or eye pain.
ü Elderly clients may develop excitement, confusion, agitation, or drowsiness.
ü Diminished doses should be used in the elderly.
ü Assess client for therapeutic effectiveness.
KEY NURSING IMPLICATIONS
Antispasmodics
1. Clients noting blurred vision, headache, urinary retention, palpitations, and indications of glaucoma are referred to the physician.
2. Antispasmodics should not be administered to clients with acute, narrow-angle glaucoma.
3. Carefully monitor elderly clients receiving antispasmodics and notify the physician if
urinary retention or indications of acute glaucoma occur.
4. Tincture of belladonna may be mixed in a small amount of applesauce or juice to mask its unpleasant taste.
5. Mouth care and sucking on hard candy may help to relieve dry mouth.
OTHER AGENTS AFFECTING GASTROINTESTINAL FUNCTION
Laxatives are drugs intended to facilitate the passage and elimination of feces from the colon and rectum.
They are used to:
§ prepare clients for a lower GI X-ray series or surgery
§ reduce the strain of defecation in clients with cardiovascular disease or in postoperative clients
§ diagnose and treat parasitic infestations of the GI tract
§ help remove unabsorbed poisons from the GI tract when oral poisonous substances have been consumed prevent or treat constipation
Laxative use by the general public is widespread but controversial because of the lack of objective data to justify their routine use. Most laxatives are used to either prevent or treat constipation.
Stimulant Laxatives
§ Contraindicated for use in clients with abdominal pain, nausea, vomiting, or rectal fissures.
§ Should only be used for short-term treatment.
§ Evaluate effectiveness of laxative.
Saline Laxatives
§ Should only be used for short-term treatment.
§ Contraindicated for use in clients with abdominal pain, nausea, vomiting, or other symptoms of appendicitis.
§ Evaluate the effectiveness of laxative.
Bulk-forming Laxatives
§ Laxative effect may not be evident for up to 3 days.
§ Contraindicated for use in clients with abdominal pain, nausea, vomiting or other symptoms of appendicitis.
§ Should be mixed with cold liquid and drunk immediately. Follow with another glass of liquid.
§ Evaluate effectiveness of laxative
Stool Softeners
§ Liquid dosage form may be given in milk, fruit juice, or formula to mask taste.
§ Action may not be evident for up to 3 days.
§ Prevents development of constipation. However, it is not used to treat existing constipation.
§ Avoid use for longer than 1 week.
§ Evaluate client for the effectiveness of these agents.
KEY NURSING IMPLICATIONS
Laxatives
1. In selecting a laxative, consider the age and general condition of the client, special restrictions due to illness, the client’s past experience with laxatives, and the time at which evacuation is desired.
2. In general, avoid the use of stimulant laxatives in the elderly.
3. Nondrug measures, such as dietary modification, fluid intake, and exercise, should
be encouraged to promote regularity.
4. Disguise the taste of castor oil.
5. Inform clients using laxatives, such as phenolphthalein and senna, that they discolor urine or feces.
6. Follow bulk-forming laxatives with at least 1 glass of fluid to prevent gastrointestinal obstruction.
7. Avoid rushing or distracting clients taking lubricant laxatives in order to prevent aspiration.
8. Support is necessary for clients taking fecal wetting agents, because they are
slow in producing effects.
9. Instruct clients using suppositories at home about proper storage and administration.
10. Always assess the effectiveness of laxatives.
11. Never administer laxatives to clients experiencing abdominal pain, nausea or
vomiting until you have consulted their physician.
12. Inform clients taking laxatives that they must drink 6–8 glasses of water to avoid
dehydration
KEY NURSING IMPLICATIONS
Antidiarrheal Agents
1. Monitor fluid intake and output and record information about the frequency
and nature of stools. Monitor body weight in infants.
2. Observe clients receiving paregoric, diphenoxylate HCl (Lomotil), difenoxin
(Motofen), or loperamide (Imodium) for CNS depression.
3. Adsorbents should not be taken within several hours of taking other oral
medications.
4. Lactobacillus products must be refrigerated.
5. Refer adult clients with fever, dehydration, or diarrhea persisting for several days to a
physician.
6. Infants and young children must be referred sooner.
KEY NURSING IMPLICATIONS
Emetics and Antiemetics
1. Identify the toxic substance ingested and call a poison control center for information.
2. Emetics are not administered to persons who have swallowed corrosive substances
or oils or to those who are unconscious.
3. Antiemetics are used carefully in clients taking other drugs with a CNS depressant
effect and are best avoided in pregnant women.
Topic 9: Other drug groups Hypoglycaemic Agents
After studying this chapter, the student will be able to:
1. Identify the official and common names of insulins currently in use
2. Describe the mechanism of action of oral hypoglycemic agents
AGENTS USED TO TREAT HYPERGLYCEMIA AND HYPOGLYCEMIA
Diabetes mellitus is a complex disorder of carbohydrate, fat, and protein metabolism caused by lack or inefficient use of insulin in the body. Insulin is secreted by the beta cells of the islets of Langerhans in the pancreas. Most cases are due to a genetically determined pancreatic insufficiency.
However, diabetes may also be the result of other pancreatic or endocrine diseases or an autoimmune response, or it can be precipitated by certain forms of drug therapy. If not effectively controlled, diabetes mellitus may increase the client’s susceptibility to cardiovascular disease and potentially cause kidney and nerve damage, as well as vision
loss due to diabetic retinopathy.
Type 1 diabetics of the type 2 diabetics, 80% have the obese, type 2 form of the disease. An additional 10% have the stable, nonobese, type 2 form. Another 10% have the unstable, or brittle, type 2 form, similar to the type 1 form. To understand the pathophysiology of diabetes mellitus, one must be aware of how the body nor
INSULIN THERAPY
Commercial insulin preparations are generally available in concentrations of 100 units per milliliter (U-100) and 500 units per milliliter (U-500).
The U-500 strength can only be purchased with a prescription and is usually employed only in clients who have a marked insulin resistance and who, therefore, require doses of more than 200 units of insulin daily. This strength is used for implantable pumps.
Insulin preparations differ with respect to their:
onset and duration of action
degree of purity
source (cow, pig or human insulin)
The onset and duration of action of insulin may be controlled by modification of regular insulin.
Regular insulin has the most rapid onset and briefest duration of action. By precipitating
insulin with zinc, various modified insulins can be produced. Another way of modifying insulin to achieve a longer onset and duration of action is to precipitate insulin with zinc and a large protein, protamine. This results in NPH (intermediateacting) and protamine zinc (PZI) insulin products.
Because of the presence of protamine, some clients may experience an immunological reaction to these products.
ORAL HYPOGLYCEMIC AGENTS
Oral hypoglycemic agents stimulate pancreatic beta cells to secrete insulin. They may also
increase the degree of binding between insulin and insulin receptors or increase the number of receptors. Some pancreatic function is required for these drugs to act. Their use is limited to the noninsulin-dependent, type 2 diabetic who does not respond to diet control alone and who is unwilling or unable to use insulin when it may be indicated.
Metformin HCl (Glucophage) is an oral hypoglycemic agent in a chemical group known as
biguanides. This drug is used in clients who have not responded to sulfonylureas or in combination with a sulfonylurea drug to take advantage of the different action of each. The client using metformin should be observed for the possible development of lactic acidosis during treatment. Over time, the use of sulfonylureas may overstimulate the pancreas which, in essence, tires out the pancreas.
Oral Hypoglycemic Agents
Note: These drugs must be used only in conjunction with a thorough client education program and follow-up supervision.
Instruction must be provided about diet, foot care, and glucose testing, plus recognizing and treating diabetic acidosis and hypoglycemia.
An increase in dose or use of insulin therapy may be required when clients are under unusual stress.
Clients must avoid alcohol, as it may produce an Antabuse-like reaction, with vomiting, flushing, and excessive
perspiration, if using sulfonylureas or increased likelihood of lactic acidosis if using metformin.
Drugs known to interact with oral hypoglycemic agents to enhance their hypoglycemic effect include salicylates,
phenylbutazone, sulfonamides, MAO inhibitors, phenytoin, and anticoagulants.
Drugs that may increase blood glucose levels include liquid products sweetened with sugar, as well as oral nasal decongestants, such as phenylpropanolamine.
Storage and Care of Insulin and Supplies
1. Before injection, insulin is brought to room temperature. This minimizes local
skin reactions.
2. Many clients are instructed in the monitoring of blood glucose levels by use of a
visually or machine-read reagent strip.
3. Some drugs may cause false-positive tests for urinary glucose
Insulin Reactions and Diabetic Ketoacidosis
1. If unsure whether the client is experiencing an insulin reaction or diabetic ketoacidosis,
it is better to treat for an insulin reaction.
2. Insulin reactions are treated by giving approximately 4 oz of a sugar-containing
beverage or other rapidly absorbed sugar, if the client is able to swallow. This is
usually followed by administration of a complex carbohydrate or regularly
scheduled meal.
3. If unable to swallow, sugar-containing syrups or pastes may be applied to the
person’s buccal mucosa.
4. Family members should be taught how to reconstitute and administer glucagon.
5. Insulin is not administered to clients who are required to fast.
6. Beta-adrenergic blocking agents may mask the signs and symptoms of hypoglycemia.
Clients are taught to respond to subtle indicators such as weakness or dizzinessTopic 10 : Other drug groups; Muscle Relaxants; Antibiotics
LEARNING OUTCOMES
After studying this chapter, the student will be able to:
1. Differentiate between a bactericidal and bacteriostatic antimicrobial agent and describe when the use of each would be appropriate
2. Differentiate between narrow and broad-spectrum antimicrobial agents and explain when each would be appropriate to use
3. Explain the common drug in use for muscle relaxant
4. Identify the appropriate nursing actions in the administration of each class of antimicrobial agents ans muscle relaxant
ANTIMICROBIAL AGENT
SUSCEPTIBILITY OF THE BODY TO INFECTION
To understand the role of antimicrobial agents in treating infections, it is important to understand those factors that may increase the susceptibility of the body to infection: age, exposure to pathogenic organisms, disruption of the body’s normal barriers to infection, inadequate immunological defenses, impaired circulation, and poor nutritional status
CLASSIFICATION OF ANTIMICROBIAL AGENTS
Several different systems are used to classify antimicrobial agents. The following discussion
briefly describes each of these systems.
Bactericidal—Bacteriostatic
Bactericidal agents are those which have a killing action on the microbial agent. Bacteriostatic agents simply inhibit the growth of bacteria, thereby permitting the host’s immunological defenses to complete the job of destroying the organism. Bactericidal agents include the penicillin’s, cephalosporins, polymyxin, and vancomycin.
The bacteriostatic category includes the tetracyclines, sulfonamides, erythromycin, and
lincomycin. Some antimicrobial agents may exert either a bactericidal or a bacteriostatic action, depending on the dose used, the causative organsm being acted upon, and/or the site of action of the drug. The use of bactericidal agents is generally preferred in the treatment of serious, life-threatening infections and/or when the host’s immunological system is not functioning properly. For the treatment of minor infections in otherwise healthy individuals, there is little difference in the overall effectiveness of bactericidal or bacteriostatic agents.
Site of Action
Antimicrobial agents may also be classified on the basis of the site at which they exert their therapeutic actions in the bacterial organism:
agents that inhibit cell wall synthesis—Some antibiotics interfere with the synthesis of the
bacterial cell wall. This results in a loss of structural integrity of the bacterial cell and
the death of the organism. Such agents are generally bactericidal in their action.
agents that inhibit protein synthesis—Some agents exert their antimicrobial effect by
interfering with protein formation in the bacterial cell. Although such an action rarely leads
to the immediate death of the organism, it does prevent normal growth and reproduction and makes it easier for host defense mechanisms to finish the job of eradicating the organism. Drugs that exert such an action are, therefore, classified as bacteriostatic agents.
agents that interfere with the permeability of the bacterial cell membrane—These drugs
increase the permeability of the bacterial cell membrane, permitting leakage of intracellular
components. As this results in the immediate death of the organism, such antimicrobial
agents are usually considered to be bactericidal in their action.
antimetabolites—Drugs with antimetabolite action generally block or alter a specific metabolic step essential for the normal function and/or growth of the bacterial cell (e.g., the
synthesis of a specific essential nutrient). This action may result in either a bactericidal or a
bacteriostatic effect, depending on the nature of the metabolic action and the concentration
of drug achieved in the environment of the organism.
Narrow Spectrum—Extended or Broad Spectrum
Antimicrobial agents are often classified as having a narrow spectrum or an extended or broad spectrum of action. Those with a narrow spectrum are useful in treating infections caused by a relatively limited number of organisms (e.g., only gram-positive organisms). Extended or broad-spectrum agents act on a wide variety of different organisms. The use of narrow-spectrum agents may be desirable when the identity of the infecting organism—as well as its susceptibility to the action of the antibiotic—has been established.
Because of their limited action, such drugs are not likely to indiscriminately disrupt the normal bacterial flora of the body. They may, therefore, be somewhat safer to use than broader spectrum drugs that might disrupt both pathogenic and useful microorganisms found in the body.
Broad or extended spectrum antimicrobial agents are useful in treating infections in which the identity and susceptibility to antimicrobial treatment of the infecting organism(s) has not been established. Because of the wide range organisms that may be susceptible to a specific broad-spectrum antibiotic, there is an excellent likelihood that the drug will be effective in treating a specific infection.
ANTIBACTERIAL AGENTS
Antibacterial agents either destroy or inhibit the growth of both pathogenic and nonpathogenic bacteria. In other words, they exert a bactericidal or bacteriostatic effect. Major antibacterial agents include the penicillins, macrolides, cephalosporins, fluoroquinolones, tetracyclines, and aminoglycosides
KEY NURSING IMPLICATIONS
penicillin’s Differ in Their:
1. chemical stability in stomach acid
2. susceptibility to penicillinase (beta lactamase) destruction
3. spectrum of action, i.e., narrow or extended
4. route of administration
5. duration of action
6. site of action
Penicillin
ü Monitor all clients receiving penicillin for signs of hypersensitivity, i.e., urticaria, laryngeal edema, skin rash, and anaphylactic shock. Discontinue therapy at the first sign of serious hypersensitivity reaction.
ü Observe clients receiving penicillin in an emergency room or physician’s office for 30 minutes before allowing them to leave.
ü Ticarcillin, mezlocillin, or piperacillin may cause bleeding abnormalities. Closely monitor clients with renal impairment.
ü Administration with bacteriostatic antibiotics, e.g., erythromycin or tetracycline, may diminish effectiveness.
ü Probenecid (Benemid) blocks renal tubular secretion of penicillins, and may cause higher blood levels and longer duration of action for penicillins.
ü High intravenous doses of sodium or potassium salts of penicillins may produce electrolyte disturbances.
ü Although not always essential, it is advisable to administer oral penicillin on an empty stomach with a full glass of water.
ü To prevent peripheral IV site irritation, avoid infusing medication rapidly
ü
Clients Receiving Penicillins
1. Take a careful medication history before administering penicillins.
2. Observe the client for indications of allergic reaction, including rash, fever, chills, and anaphylaxis.
3. Oral penicillins should be given 1–2 hours before or 2–3 hours after meals.
4. Injection sites must be checked carefully for signs of local reactions (e.g., redness,
phlebitis). Do not use the same needle for withdrawing the solution from the vial and administering it.
5. Never give procaine penicillin intravenously.
Cephalosporins
· Monitor clients for signs of hypersensitivity, i.e., urticaria, laryngeal edema, skin rash, and anaphylactic shock.
· Discontinue therapy at first sign of serious hypersensitivity reaction.
· Use with caution in clients with renal impairment.
· Make IM injections deep into musculature to reduce inflammatory reactions.
· IV administration for prolonged periods or in high doses may cause thrombophlebitis. Use small gauge IV needles, large veins, and alternate infusion sites to reduce risk of such problems.
· Bacteriostatic antimicrobial agents (e.g., erythromycins or tetracyclines) may interfere with cephalosporins' bactericidal action.
· Probenecid administered with cephalosporins may increase and prolong their plasma levels by interfering with their renal tubular secretion.
· Use of potentially nephrotoxic drugs, such as aminoglycosides or loop diuretics, with cephalosporins may increase likelihood of renal toxicity.
· Use may result in a false positive reaction for glucose with Benedict's solution or Clinitest tablets. Glucose tests based on enzymatic reaction (e.g., Clinistix or Tes-Tape) are not affected by cephalosporin use.
· Monitor clients for gastrointestinal distress, renal impairment and hematological changes. In clients with renal impairment, consult product information and adjust cephalosporin dose accordingly.
Clients Receiving Cephalosporins
1. Clients who are allergic to penicillin may also be allergic to cephalosporins.
2. Administer intramuscular injections into a large muscle mass to decrease pain.
3. Observe intravenous sites carefully for phlebitis
Tetracyclines
· Avoid use in children under 8 because of possible interference with development of teeth and bones and staining of teeth.
· Clients must avoid unprotected exposure to direct sunlight or UV light to reduce risk of phototoxicity.
· IV therapy in excess of 2 g/day of drug may produce hepatotoxicity.
· Should not be used during pregnancy.
· Monitor clients for bacterial or fungal superinfection, particularly involving the GI tract and/or vagina.
· Avoid use with calcium supplements, antacids, iron, or dairy products as these may reduce tetracycline absorption
Clients Receiving Tetracyclines
1. Avoid administering tetracycline simultaneously with sodium bicarbonate, iron
preparations, dairy products, and drugs containing zinc, aluminum, calcium, or
magnesium.
2. Avoid administration of tetracycline on an empty stomach.
3. Clients should avoid excess exposure to the sun or use a sunscreen if taking
demeclocycline.
4. Superinfections may develop. Good oral care is essential. Women prone to the
development of vaginal infections should advise the physician about this before
beginning therapy.
5. Because of effects on teeth and bone, tetracyclines are generally avoided in children under 8 years and in women during the last two trimesters of pregnancy.
6. Never administer a tetracycline preparation containing procaine intravenously.
Macrolides/Erythromycins
· Monitor clients for signs of hepatotoxicity, i.e., malaise, nausea, vomiting, abdominal cramping, fever, jaundice, and/or abnormal hepatic function tests.
· Hypersensitivity reactions may occur in some clients, ranging from mild skin rashes to anaphylaxis.
· Oral doses should be taken 1 hour before or 2 hours after meals. Administer with food if GI upset occurs
Aminoglycosides
· Monitor clients for signs of nephrotoxicity.
· Neuromuscular blockade and respiratory paralysis may occur when administered with or shortly after anesthetics or muscle relaxants.
· Provide good hydration to reduce likelihood of nephrotoxicity or neurotoxicity.
· Avoid use of other drugs that produce ototoxicity, nephrotoxicity, or neurotoxicity.
· To prevent peripheral IV site irritation, avoid infusing medication rapidly.
Clients Receiving Aminoglycosides
1. Obtain an accurate body weight before therapy is begun.
2. Observe the patient for nephrotoxicity and eighth cranial nerve damage (hearing and balance problems).
3. When aminoglycosides are used for treating urinary tract infections, avoid urine acidifiers such as cranberry, plum, and prune juices, as well as vitamin C.
4. Monitor peak and trough levels.
Other Antibacterial Agents
ü Report evidence of allergic reaction, such as rash or itching.
ü Report symptomatic improvement.
ü Review administration and storage instructions that accompany product.
ü To prevent peripheral IV site irritation, avoid infusing medication rapidly. Monitor site
Sulfonamide Products for Systemic Use
ü Administer drugs on an empty stomach.
ü Monitor for development of hypersensitivity reactions, particularly in clients with severe allergies or bronchial asthma. Skin rash is a common indication of hypersensitivity.
ü Maintain adequate fluid intake to prevent crystalluria and stone formation.
ü Monitor for development of hematological changes, such as a drop in white blood cell count.
ü Protect client from direct sunlight or UV light to avoid phototoxic reaction.
ü Initial therapy with these products may require somewhat higher doses than those listed below.
ü Report symptomatic improvement
Antitubercular Drugs
ü Determine prior use of these medications and therapeutic response.
ü Note color and nature of sputum.
ü Teach client appropriate hygiene to ensure safety of others.
ü Stress the importance of completing the course of treatment
Antiviral Drugs
ü Many viruses cannot be treated with antivirals because, by the time symptoms arise, the viruses have already replicated and most antiviral action is during replication.
ü Used for a variety of viral infections from influenzae A, herpes simplex, RSV, AIDS-related Kaposi sarcoma, pneumocystis’ carinii pneumonia associated with AIDS, HIV infections
Clients Receiving Antiviral Agents
1. Amantadine HCl should be taken after meals. Clients are observed for orthostatic
hypotension, depression, gastrointestinal distress, and urinary retention.
2. Clients receiving vidarabine should have intake and output monitored and be
weighed daily.
3. A filter is used for vidarabine infusions.
4. Acyclovir is always administered intravenously as an infusion. Watch for nephrotoxicity, phlebitis, nausea, and vomiting, plus the development of hypersensitivity reactions.
Clients Taking Antimicrobial Drugs Should:
1. Know the drug’s name, dosage, administration schedule, and why the medication
is being taken.
2. Know any special instructions related to storage (e.g., refrigerate medication) and
administration (e.g., do not take with milk or milk products).
3. Be told the major adverse effects and what to do if these should occur.
4. Be advised never to use an expired medication.
5. Be encouraged to complete the course of treatment as prescribed.
6. Be instructed not to give their medication to someone else, as it may result in an
adverse reaction.
7. Avoid taking any antimicrobial drug that has not been prescribed for a particular
course of illness.
8. Report failure of the medication to successfully treat the infection.
9. Be encouraged to keep all follow-up appointments
Clients Receiving Antifungal Agents
1. Never reconstitute amphotericin with saline or water containing a bacteriostatic agent. Use only sterile water for injection, USP, with a bacteriostatic agent.
2. Intravenous solutions of amphotericin should be added to infusions of dextrose and water only.
3. Never use a solution of amphotericin which contains a precipitate. Use a prepared amphotericin solution within 24 hours or refrigerate it and protect it from light.
4. Monitor the vital signs and intake and output of all clients receiving amphotericin and miconazole infusions. Observe the client for fever, nausea, chills and headaches and for hypokalemia if the client is receiving amphotericin.
5. Observe the intravenous injection site for indications of phlebitis
NEUROMUSCULAR BLOCKING AGENTS
Sometimes it is clinically desirable to relax or inactivate one or more skeletal muscles to:
facilitate surgery by reducing muscle movement and/or to permit use of lower anesthetic
doses facilitate electroconvulsive therapy (ECT) by reducing excessive muscular contraction
prevent muscle spasm of the larynx (laryngospasm) in clients who require endotracheal
intubation aid in the treatment of tetanus (a disease characterized by severe muscle spasm)
Neuromuscular Blocking Agents (Intravenous)
§ Low serum potassium levels antagonize the action of these drugs, with acidosis potentiating their effects.
§ Antidotes (for competitive blocking agents) and emergency equipment to support respiration must be available when these drugs are given.
§ Monitor vital signs frequently after administration.
§ Evaluate the therapeutic effectiveness of these agents.
Neuromuscular Blocking Agents
1. Obtain a history of current drug use and drug allergies before neuromuscular
blocking agents are used.
2. Antidotes such as the anticholinesterase muscle stimulants and emergency equipment must always be available when these drugs are used.
3. Monitor vital signs carefully
Skeletal Muscle Stimulants
1. Assess the client’s ability to swallow, ptosis of the eyelids, and muscle strength
as well as vital signs.
2. Contact the physician whenever the client develops a weakened condition
that may be related to myasthenic crisis or cholinergic crisis.
3. Clients with myasthenia gravis should receive their medication early in the
morning before they eat or engage in self-care activities.
4. Physical activities are planned for the time shortly after taking medication
when the muscle strength is greatest.
5. Clients with myasthenia gravis are instructed to carry information about
their medication and must understand the importance of complying with the
medication schedule
CLIENT TEACHING
1. The nurse stresses safety measures for clients taking skeletal muscle relaxants that depress the (CNS). These measures include avoiding concomitant use of other drugs that depress the CNS, including ethanol, and avoidance of hazardous tasks, such as driving.
2. Clients taking skeletal muscle stimulants to treat myasthenia gravis need to be
informed concerning signs and symptoms of cholinergic crisis, so they can report these
to their physician and seek immediate medical care.
3. Clients with myasthenia gravis should be instructed to wear identification indicating
that they have the condition.
4. Clients with myasthenia gravis should be instructed to take their medication early in the
morning before breakfast and the importance of adhering to a strict schedule of medication
self-administration.
5. Clients with myasthenia gravis should be informed not to take any prescription or overthe-counter medication without consulting their physician.
Anti-Parkinson Drugs
1. Clients taking levodopa should be monitored for orthostatic hypotension and cardiac arrhythmias. Also watch for psychiatric disturbances.
2. Record the client’s positive responses to treatment as well as side effects experienced.
3. Clients taking amantadine are observed for psychological changes, orthostatic
hypotension, urinary retention, and gastrointestinal symptoms.
4. Anticholinergics may produce dry mouth, urinary retention, and constipation and may precipitate an acute attack of glaucoma. Monitor clients carefully.
5. Do not rush the client during administration of oral medications.
6. Clients taking levodopa should avoid foods and medications containing substantial amounts of pyridoxine (vitamin B6).
Self check
1. Explain common drud use for antibiotics and muscle relaxant
2. Explain nursing consideration when administering these two categories of drugsTopic 11 : Current issues and trends in Medication Administration • Methods of administering medications • Technology influence • Drug calculation • Look Alike Sound Alike (LASA) drugs • Medication errors and reporting systems
Based on video shared, discuss about the current issue that you facing in your organization.
Discuss about policy or management medication errors.
Topic 12 : Current issues and trends in medication and parenteral nutrition administration • Oral/ Sublingual and parenteral administration practices
Based on the video shared, discuss what is the current practice about :
1. Oral/Sublingual administration
2. Parenteral administration
- Intramuscular
- Subcutanoues
- Intravenuos
Topic 13: Nutrition • Introduction to nutrition •Nutritional Assessment • Balance diet • Client nutritional needs • Factors affecting diet intake • Effects of over- and under- nutrient in diet
After studying this chapter, the student will be able to:
1. Identify the roles of protein, fat, and carbohydrate in human nutrition
2. List the major vitamins and minerals required for health
3. List the fat-soluble and water-soluble vitamins and indicate the common circumstances in which a deficiency of each could occur
4. Apply the nursing process for clients receiving total parenteral nutrition (TPN)
It has been well established that about 50 nutrients are required by the human
body. Of these, 10 are considered “leader nutrients”—protein, carbohydrate, fat,
vitamin A, vitamin C, thiamine, riboflavin, niacin, calcium, and iron. If proper
amounts of these nutrients are supplied in the diet, the other 40 will probably be
consumed in amounts sufficient for the body’s needs. The level of these “leader
nutrients” is usually listed on the information panels of food labels, thereby permitting the consumer and health professional to compare the nutritional content of various food products.
Estimates of daily requirements of most of the 50 required nutrients, known as
Recommended Daily Allowances (RDA), have been established and published periodically by the National Research Council (NRC). The RDA of a nutrient is the level of intake considered by the NRC Food and Nutrition Board to be adequate, on
the basis of available scientific knowledge, to meet the known nutritional needs of
practically all healthy persons. In using the RDA levels, one should remember that
they are:
Recommendations for the total amount of nutrient that should be consumed each day.
Allowances must be made for nutrient losses possible in food processing and preparation
Recommendations meant to maintain health and may not cover special nutritional needs that arise during illness estimates of the needs of most members of large population groups and may not be appropriate for each member of the group.
Nutrients may be classified into several categories, including proteins, fats, carbohydrates, vitamins, and minerals. Each of these categories is considered briefly.
PROTEIN
Protein is essential for the synthesis, maintenance, and repair of body tissues; for energy production; for the continuation of enzymatic and immunological processes; and the maintenance of osmotic pressure in the vasculature. Protein is made up of component parts known as amino acids. Of the 22 amino acids, 8 are considered essential, or indispensable, for human nutrition; the body cannot synthesize them at levels sufficient to meet its needs. During digestion, dietary protein is broken down into its amino acid components. The body then reassembles the amino acids into many different proteins, each serving a specialized function. Different foods supply protein of differing value to the human body, depending upon the nature of the amino acids in the protein source. Highquality protein (e.g., protein derived from meat, fish, poultry, eggs, and milk) supplies the 8 indispensable amino acids in usable proportions.
Protein derived from vegetables and grains is often lower in nutritional quality, because certain essential amino acids may be missing or in insufficient quantity. By carefully combining protein from varying sources, adequate amino acid intake can be assured.
Protein generally supplies about 4 large calories(kcal) of energy per gram. Clients who cannot digest dietary protein properly may use products containing the essential amino acids in their pure form. These may be supplied orally in the form of an elemental diet or parenterally as part of a total parenteral nutrition (TPN) regimen.
FAT
Fat is a very concentrated dietary source of energy that supplies about 9 kcal/g of energy. Fat provides the body with essential fatty acids and, along with carbohydrates, helps to spare protein for its tissue-building and repairing functions. Fat is also a carrier of fat-soluble vitamins (A, D, E, and K), hormones, and components of human cell membranes. Fat deposits in the body also help to support vital organs and provide insulation.
During digestion, dietary fats are broken down to fatty acids. One of these, linoleic acid, is essential for life and must be supplied by the diet, as the body cannot manufacture its own supply. A deficiency of fatty acids rarely occurs, because the body’s daily need for fat can be met with only 15–25 g of dietary fats. At greatest risk for development of essential fatty acid deficiency are clients receiving special nutritional therapy utilizing elemental oral feedings or TPN as the sole nutritional source.
CARBOHYDRATE
Sugars and starches are the principal kinds of carbohydrate. Starches are complex forms of sugar. Most sugars and starches are eventually converted by biochemical reactions of the body to glucose (one of the body’s most important fuels). It is either readily utilized by the cells and tissues of the body or it is stored by the liver and muscles as glycogen. The availability of carbohydrates as an energy source spares protein from being used for energy, thereby allowing it to be used for tissue
growth and repair. Carbohydrates also aid in fat utilization and prevent the breakdown of fat in the body. When utilized by the body, carbohydrates contain about 4 kcal/g of energy.
MINERALS
Minerals are found in water and in natural foods. They may be divided into two groups: major elements and micronutrients. The major elements are calcium, phosphorus, magnesium, sodium, potassium, chloride, and sulfur. The
micronutrients are iron, copper, iodine, manganese, zinc, fluorine, cobalt, chromium, molybdenum, and selenium
Micronutrients (Trace Elements)
Many chemical elements play an important role in the functioning of the human body even though their concentration may be quite low. Among these trace elements are copper, chromium, and selenium. Copper is associated with iron in
enzyme systems and hemoglobin synthesis. Chromium is associated with glucose metabolism and lowers serum cholesterol (LDL— low-density lipoproteins) and increases HDL—high-density lipoprotein commonly known as “good cholesterol.” No RDA standards have been established for copper or chromium. Selenium is a structural component of teeth and is a synergistic antioxidant with vitamin E. Recent studies have shown it to be useful in both preventing and treating
prostate cancer. The RDA of selenium is 55 mcg/d. Deficiencies of these substances are rare since they are often present in minute amounts in many dietary sources. Deficiencies of micronutrients may occur when a client is exclusively consuming
a carefully controlled synthetic diet, as in the use of infant formulas by neonates and in TPN
NURSING IMPLICATIONS
Clients Taking Vitamin and Mineral Supplements
1. Nurses can be instrumental in educating the public about an adequate diet and the benefits and hazards of vitamin therapy.
2. Individuals at risk of nutritional deficiencies include pregnant women, infants and children, individuals with eating disorders, persons on fat diets, persons with chronic GI disorders, alcoholics, drug-dependent persons, and the elderly.
3. Nursing assessment includes evaluation of the client’s nutritional status using information from a dietary history, health history, physical examination, and laboratory studies.
4. The absorption of fat-soluble vitamins may be reduced in persons using mineral oil or cholestyramine resin. Mineral oil should not be taken with meals or vitamin supplements.
5. Oral potassium supplements should be taken after meals or with food and with a full glass of water to decrease GI upset.
6. Tablets containing potassium supplements must not be chewed or crushed.
7. Clients taking potassium supplements are monitored for the development of gastrointestinal distress or GI bleeding.
8. Parenteral potassium is infused slowly. Infiltration may be associated with tissue necrosis.
9. Ion exchange resins, such as polystyrene sulfonate (Kayexalate), may be given orally or rectally as a retention enema.
10. Calcium supplements should be taken in divided doses approximately 1 hour after meals. Encourage exposure to sunlight, weight-bearing exercise, and compliance with other medications intended to prevent osteoporosis.
11. Maximum benefit from fluoride supplementation is achieved by chewing and retaining the product in the mouth before swallowing it.
12. Assess the weight, blood pressure, and intake and output of clients receiving TPN. Monitor for the development of complications, such as infection.
13. No drugs are added to the TPN line without prior consultation with the pharmacist to determine possible incompatibilities.
VITAMINS
Vitamins are chemical substances that regulate and/or participate in chemical reactions within the body. They are generally not synthesized in sufficient quantities by the body to supply its needs. This category of nutrients is, perhaps, the most controversial. Although most people believe that vitamins are important and essential for good health, some believe that if a little is good, more is better.
Topic 14:Meet the nutritional needs of clients: • Therapeutic diet • Fluid balance • Health education • Total parenteral nutrition (TPN)