Administering Medications Flashcards
What are drugs?
“Chemicals that interact with a living organism and alters its activity”
Diagnosis (radiopaque agents, contrast dyes)
Treating
Preventing (immunizations)
Drug Names
Chemical Name
Chemical composition & molecular structure of drug
Rarely used in nursing
Generic Name
Assigned by US Adopted Name Council
ibuprofen
Brand Name (Trade)
Proprietary
Motrin®
Prescription drugs vs non-prescription drugs or over-the-counter (OTC)
ibuprofen 200 vs ibuprofen 800
Drug Classification
Grouped w/similar characteristics Grouped by basic characteristics * Usage * Body system * Chemical composition
One drug can be placed in more than one category
Classified by usage - ibuprofen can be used as an analgesic, anti-inflammatory, or antipyretic
Classified by body system - valium can be used for its anti-anxiety effects or for its effects in decreasing intestinal system activity & other smooth muscles
Promoting Drug Quality and Safety
- Drug listings & directories
- Pharmacopoeia & formularies
- Nursing drug handbooks
- Physician’s Desk Reference
- Pharmacology texts
- A clinical pharmacist; medication package inserts
Promoting Drug Quality and Safety cont’d
- Legal considerations
- US drug legislation
- Sets official drug standards
- Defines prescription drugs
- Regulates controlled substances; improves safety; requires proof of efficacy
Promoting Drug Quality and Safety cont’d
- Nurse Practice Acts
- Identify nursing responsibilities for admin & client monitoring
Food and Drug Administration (FDA) of US DHHS
- Regulates the manufacture & sale of all medications & monitors their safety & effectiveness
- Also regulates, through controlled clinical trials, the testing of any med’n that is to be marketed & sold in the US
Promoting Drug Quality and Safety cont’d
Storing & Distribution Systems
- Stock supply
- Bulk quantity
- Central location
- Not client specific
- Requires measuring each dose
- Cost-effective
Promoting Drug Quality and Safety cont’d
Storing & Distribution Systems
- Unit dose
- Individually packaged
- Client-specific drawers
- 24-hr supply
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Is the prescribed amount of drug the patient receives at a single time; each one (usually one tablet) is individually packaged & labeled w/drug name, dose, & expiration date
Unit dose
Promoting Drug Quality and Safety cont’d
Storing & Distribution Systems
- Automated dispenser
- Password-accessible locked cart
- Computerized tracking
- Can combine stock & unit doses
- Pyxis or Omnicell
Promoting Drug Quality and Safety cont’d
Storing & Distribution Systems
- Self-administration Medication (S A M)
- Individual containers
- Kept @ client’s bedside
i.e. sublingual nitroglycerin
Pharmacokinetics
What happens to the drug in the body?
- The principles of ADME
Pharmacokinetics
Refers to the absorption, distribution, metabolism, & excretion of a drug
These 4 processes determine the intensity & duration of a drug’s actions
Pharmacokinetics
Absorption
* From site of administration to blood stream
Distribution
* From bloodstream to sites of action
Pharmacokinetics
Metabolism
- Breakdown of medication to be excreted
- Mainly in the liver
Excretion
* Excretion from the body
?
Is the transportation of a dug in bodily fluids (usually the bloodstream) to the various tissues & organs of the body
- Intended & unintended effects can occur
- Rate depends on adequacy of local blood flow in target area; also influenced by permeability of capillaries to drug’s molecules as well as protein-binding capacity of drug
Distribution
?
(or biotransformation); is the chemical inactivation of a drug through its conversion into a more water-soluble compound or into metabolites that can be excreted from the body
Metabolism
Absorption
Factors affecting absorption
- Route of administration
- Drug solubility
- pH/ionization
- Blood flow
The form (preparation) of a drug usually determines its route of administration
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Refers to the ability of a medication to be transformed into a liquid form that can be absorbed into the bloodstream
Drug solubility
Enteric-coated drugs can’t be decomposed by gastric secretions; the coating thus prevents the med’n from being diluted before it reaches the intestines
In this way, the coating delays the action of the med’n; also decreases irritating effects of the med’n on the stomach
pH (relative acidity or alkalinity) of local environment also affects drug absorption
Acid content of stomach aids in transporting the med’n across the mucous membranes, so acidic med’n, like aspirin, are more readily absorbed in the stomach than basic (alkaline) med’n, like sodium bicarbonate, which are readily absorbed in the more alkaline SI
Ionized molecules are lipid insoluble & thus can’t pass easily through the phospholipid layer of cell membranes
Distribution
Factors affecting distribution
- Local blood flow
- Membrane permeability
- Protein-binding capacity
A drug’s tendency to bind to plasma proteins in the blood also affects distribution. For a given amount of a drug, some molecules bind to plasma proteins, & the remainder will be “free”
Tylenol (nearly all free in bloodstream & are pharmacologically active) vs warfarin (Coumadin) whose effects produced by 1% of molecules that’re free
Metabolism
Factors affecting metabolism
- Liver function
- Health/disease status
- First-pass effect
Metabolism takes place mainly in the liver, but med’ns can be detoxified also in the kidneys, blood plasma, intestinal mucosa, & lungs
First-pass effect
Oral med’ns are absorbed from the GI tract & circulate through the liver before they reach the systemic circulation
Many oral med’ns can be almost completely inactivated this way; this inactivation is known as the first-pass effect
For this reason, oral med’ns formulated w/a higher concentration of the drug than are parenterals
Excretion
Factors affecting excretion
- Organ function, especially the kidneys, liver, & lungs
- Exocrine glands
Common organs of excretion: lungs, exocrine glands, liver, GI tract, & kidneys (primary site of excretion)
Adequate fluid intake facilitates excretion; if decreased renal function (check BUN/creatinine) to monitor for drug toxicity
Exocrine glands (sweat & salivary glands) can also occur w/oral agents
The client has been on a low-protein diet. This will most likely affect which pharmacokinetic process?
a. absorption
b. excretion
c. distribution
d. metabolism
Answer: c
A low-protein diet may lead to an inadequate level of plasma proteins, which will affect availability of “free” drug
Concepts related to Pharmacokinetics
- Time until onset, peak, & duration
- Therapeutic range
- Peak level
- Trough level
- Therapeutic level
- Biological half-life
- Concentration of active drug
Some drugs, like warfarin & digoxin, have narrow therapeutic range. Small dose changes cause therapeutic failure or adverse drug reactions. Blood levels are done frequently in order to know correct drug dosage to give.
?
Is the time needed for drug concentration to reach a high enough blood level for its effects to appear (is the minimum effective concentration)
onset of action
?
When the concentration of medication is highest in the blood, the medication has reached its ___
peak action
___ : period of time in which drug has a therapeutic effect (before metabolized and excreted)
Duration
?
Is the concentration of a drug in the blood serum that produces the desired effect w/o toxicity
Therapeutic range
Is a range of therapeutic concentrations; @ onset of action, serum drug level is minimal
?
Occurs when the drug is @ its highest concentration (when the rate of absorption is equal to the rate of elimination)
After that, metabolic & excretory processes begin to remove the drug from the tissues & blood
Peak level
?
Occurs when the drug is at its lowest concentration, right before the next dose is due
Trough level
?
Is the amount of time it takes for half of the drug to be eliminated
Biological half-life
Factors Affecting Pharmacokinetics
- Age
- Body mass (weight)
- Gender
- Pregnancy (contraindication)
- Environment
- Route of administration (IV faster than oral)
Factors Affecting Pharmacokinetics cont’d
- Timing of administration (presence of food in GI tract)
- Fluids (dehydration affects absorption)
- Pathological states (liver/kidney disease)
- Genetic factors
- Psychological factors
Pharmacodynamics: Effects of Drugs
Primary effects
- Therapeutic effects
- Predicted
- Intended
- Desired
- Why the drug was prescribed (palliative, supportive, substitutive, chemotherapeutic, restorative)
Pharmacodynamics: Effects of Drugs cont’d
Secondary effects
- Unintended
- Nontherapeutic
- Can be predictable, harmless, harmful
Pharmacodynamics: Effects of Drugs cont’d
Types of secondary effects
* Side effects
- Adverse reactions
- Toxic reactions
Pharmacodynamics: Effects of Drugs cont’d
- Allergic reactions
- Idiosyncratic reactions
- Cumulative effect
Pharmacodynamics: Effects of Drugs cont’d
Types of secondary effects
* Side effects
- Adverse reactions
- Toxic reactions
Pharmacodynamics: Effects of Drugs cont’d
- Allergic reactions
- Idiosyncratic reactions
- Cumulative effect
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Are unintended, often predictable, physiological effects that are usually well tolerated by patients
Occur @ the usual prescribed dose & may be immediate or delayed
Side effects
Most common: nausea, vomiting, diarrhea, dizziness, drowsiness, dry mouth, abdominal distension or distress, & constipation
?
Are harmful, unintended, usually unpredicted reactions to a drug administered at the normal dosage; are more severe than side effects & often require discontinuation of the drug
Adverse reactions
?
Are dangerous, damaging effects to an organ or tissue
May be caused by overdosing; accumulation of drug in tissues (r/t long-term use or incomplete metabolism/excretion); or abnormal sensitivity or allergic response to drug
Toxic reactions
?
Are dangerous, damaging effects to an organ or tissue
May be caused by overdosing; accumulation of drug in tissues (r/t long-term use or incomplete metabolism/excretion); or abnormal sensitivity or allergic response to drug
Toxic reactions
?
Are unexpected, abnormal, or peculiar responses to medications
May take the form of extreme sensitivity to a medication, lack of response, or a paradoxical (opposite of expected) response, such as agitation in response to a sedative
Idiosyncratic response
?
Are unexpected, abnormal, or peculiar responses to medications
May take the form of extreme sensitivity to a medication, lack of response, or a paradoxical (opposite of expected) response, such as agitation in response to a sedative
Idiosyncratic response
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Is the increased response to repeated doses of a drug that occurs when the rate of administration is greater than the rate of metabolism & excretion
Cumulative effect
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There is an additive effect; the effect of both drugs together is greater than the individual effects
Synergistic
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One drug interferes w/the actions of another & decreases the resultant drug effect; the combined effect is less than that of one drug given alone
Antagonistic
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Occur when multiple drugs are mixed together, causing a chemical deterioration of one or both drugs
Result is an “incomplete solution” that should not be administered
You can usually recognize these when the mixed solution takes on a changed appearance
Incompatibilities
?
Occur when multiple drugs are mixed together, causing a chemical deterioration of one or both drugs
Result is an “incomplete solution” that should not be administered
You can usually recognize these when the mixed solution takes on a changed appearance
Incompatibilities
Drug Abuse & Misuse
- Tolerance
- Dependence
- Abuse
- Illicit drugs
Measure & Calculate Dosage
Measurement systems
- Metric
- Apothecary
- Household
- Units
- Milliequivalents
Calculating Dosages
- Ratios
- Solving for X
- Nomograms (body surface area for infant drug calculations)
- Clark’s rule (pediatric calculations)
Units and mEq cannot be directly converted to the apothecary, metric, or household system
?
Indicate the strength of the ion concentration in a drug
Is the # of grams of a solid contained in 1 mL of a solution
i.e. electrolytes like potassium chloride (KCl)
Milliequivalents (mEq)
- You must always read the container label to know the # of units per milliliter
Not all units are the same
1 mL of heparin does NOT contain 100 units of heparin
Insulin, a drug used by diabetics to help control blood sugar, is measured in units, with 100 international units being the standard strength prescription
In this strength, 1 mL of the fluid medication contains 100 units of insulin
Nursing Considerations: Medication Prescription
Types of medication prescriptions
- Written prescription
- Automatic “stop” date (i.e. most narcotic prescriptions are in effect for only 7 days)
- STAT prescription
- Single (or one-time; i.e. before surgery or diagnostic procedures)
- Standing prescription
- A prn prescription (i.e. pain medications, antiemetics, laxatives)
Nursing Considerations: Medication Prescription cont’d
Communication of prescriptions (orders)
- Handwritten
- Preprinted
- Oral
- By telephone
Medication Errors
- Lack of knowledge or information
- Sound-alike, look-alike; look-alike, sound-alike, & “high-alert”
- Faulty communication
- Equipment errors
- Calculation & measurement errors
- Other
- Improper handling & storage
- Not following the 6 rights
- Environmental (lighting)
- Fatigue, distractions, or interruptions
Lack of knowledge of the drug is the most common factor contributing to medication errors
Lack of information about the patient is the 2nd most frequent cause of errors
A drug is given by the wrong route
Never use a “trailing zero” with medication orders
Do NOT use 1.0 mg; use 1 mg
1.0 mg could be misread as 10 mg, resulting in a 10-fold dose increase
Always use a “leading zero” for decimal dosages
Do NOT use .25 mg; use 0.25 mg
.25 mg may be misread as 25 mg
Medication Reconciliation
- “Reconcile” medications @ all points of entry & exit
- List of all patient medications including OTC
- Ensures that there are no discrepancies
- Done at each stage of health care delivery (admission, status change (i.e. from critical to stable), patient transfers, discharge)
Technology to prevent errors
- Computerized prescriber order entry (CPOE)
- Barcode medication administration
- Smart pumps
- Automated dispensing cabinets (Omnicell, Pyxis)
Assessment - Medications
- Before
- During
- After
- Medication history
- Physical examination
Analysis/Nursing Diagnosis
- Injury Risk
- Ineffective Health Management
- Knowledge deficit
- Impaired physical mobility
- Impaired memory
- Impaired swallowing
?
Is the ingestion of numerous medications in an attempt to treat many conditions simultaneously
People self-prescribe or rely on OTC’s for symptom relief; may continue taking them in combination w/prescribed medications
Polypharmacy
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Is failure to consistently integrate a therapeutic regimen for illness into daily living
Ineffective Health Management
Teaching Medication Self-Administration
- Know and understand what you are taking
- Take the drug as prescribed
- Communicate w/your provider
- Think about safety
- Administer your drugs correctly
- Store your drugs safely
- Maintain your supply
Nursing: Medication Administration Safety
3 checks
- Before you pour, mix, or draw
- Check the medication label against the medication administration record (MAR)
- After you prepare or pour
- Verify the label against the MAR
- At the bedside
- Check the medication again
Nursing: Medication Administration Safety cont’d
6 rights
- Right drug
- Right dose
- Right time
- Right route
- Right patient
- Right documentation
Other rights
- Right reason
- Right to know
- Right to refuse
Routes of Administration
- Oral medications
- Most commonly used
- Includes
- Tablets, capsules
- Liquids
- Buccal
- Sublingual
- Enteral medications
Enteral medications
For patients who cannot swallow or who have feeding tubes, you can give oral medications through nasogastric (NG), gastrostomy, or jejunal tubes
Hydrophilic meds (Metamucil) can’t be administered via a tube b/c they attract water & will solidify in tube
Crushing tabs - enteric-coated & extended release should not be crushed
Continuous tube feeding - tube feed must be stopped for med administration and then resumed
Enteral tube suction - d/c suction for 30 min after administration & keep clamped for absorption
Routes of Administration cont’d
- Topical medications: applied directly to body surface/body cavities
- Local (& sometimes systemic) effects
- Lotions, creams, ointments
- Transdermal patches
- Eye & ear
- Nasal
- Vaginal
- Rectal
Routes of Administration cont’d
- Respiratory inhalations
- Use concept of nebulization
- Absorption via alveoli & blood supply
> Atomizers
> Aerosol
> Metered dose inhaler (MDI) - delivers measured doses of a nebulized drug; pressurized cannister can be used w/spacer to allow for a more accurate amt of inhaled med
?
Is the production of a fine spray, fog, powder, or mist from a liquid drug
Nebulization
Routes of Administration cont’d
Parenteral medications
- Intradermal
- Subcutaneous
- Intramuscular
- Intravenous
Pro’s - absorbed faster & more completely; more predictable & dosages measured more accurately
Con’s - damage to tissues if not appropriate route (IM vs SQ)
Must use aseptic technique
Parenteral Drug Administration
- Equipment preparation
- Syringe/needle (size, gauge)
Parenteral Drug Administration
- Medication preparation
- Vials & ampoules
- Reconstituting from powder
- Two medications in one syringe
> Example mixing insulin
> Clear before cloudy
Needle length 3/8 in to 3 inches
Filter needles or filter straws - vials or ampules particles of glass
Syringes - tip luer-lock (twist-on) or non luer-lock (snap-on)
0.5 - 60 mL different sizes
Standard syringes, tuberculin syringes, & insulin syringes (units per mL)
Needle length 3/8 in to 3 inches
Filter needles or filter straws - vials or ampules particles of glass
Syringes - tip luer-lock (twist-on) or non luer-lock (snap-on)
0.5 - 60 mL different sizes
Standard syringes, tuberculin syringes, & insulin syringes (units per mL)
Pre-filled unit-dose systems that need a Carpuject to administer med
Disposable pre-filled system - Lovenox (enoxaparin)
Heparin
- Fast-acting
- Interrupts blood clotting process
- Used on patients who have had surgery, CVA, or MI
- Dosage is based on weight & results of blood coagulation studies
- Given IV or SC
- SC deep abdomen 2 in away from umbilicus & rotate sites
- Do not massage, just apply pressure
Parenteral Drug Administration cont’d
Safety issues
- Use sharps containers
- Avoid recapping a dirty needle
Use the correct site
* Wrong site could mean wrong route
Be familiar w/the technique required for the medication (i.e. heparin, insulin)
Parenteral Drug Administration cont’d
- Intravenous medications
- IV push (IV push does NOT mean push rapidly!)
- IV piggyback (intermittent infusion)
- Secondary vs Primary (continuous)
- Medicated drips
IV piggyback
With an IV piggyback setup, the smaller (secondary) container is connected to the primary (continuous) infusion line at the upper (primary) port
Setup allows for intermittent use only; i.e. antibiotics
SCRUB the HUB for 15 seconds
Most intermittent medications are mixed in 50-250 mL of 5% dextrose in water or NS & delivered over a period of time (30-60 min) @ regular intervals q6-8 hrs
Medicated drips are usually seen in the ICU like dopamine or heparin drips
Central venous access devices can also be used as a long term access for medications that needs to be delivered long-term
