Chapter 31 Medication Administration PDF

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Chapter 31: Medication Administration (fill in sections as you go and add any missing or needed info) SCIENTIFIC KNOWLEDGE BASE - Patients with health problems use a variety of strategies to restore or maintain their health: 1. One strategy is medication - Nurses play an essential role in preparing, administering, and evaluating the effects of medications. - Family caregivers, friends, or home care personnel often administer medications when patients cannot administer them themselves at home - Nurses are responsible for: 1. evaluating the effects of medications on the patient’s ongoing health status 2. providing education about medications and side effects 3. encouraging adherence to the medication regimen 4. evaluating the patient’s and family caregiver’s ability to administer medications - Administering medications safely requires an understanding of legal aspects of health care, pharmacology, pharmacokinetics (the movement of drugs in the human body), the life sciences, pathophysiology, human anatomy, and mathematics Medication legislation and standards: - Federal regulations: - First American law for medication regulation → Pure Food and Drug Act - Requires all medications be free of impure products. - FDA enforces medication laws that ensure all meds on the market undergo testing before they are sold to the public. - 1993 - MedWatch program: encourages nurses and other HCPs to report (via MedWatch form) when a med, product, or medical event causes serious harm to a patient. - Official publications such as the United States Pharmacopeia (USP) a  nd the National Formulary  set standards for: - Medication strength - Quality - Purity - Packaging - Safety - Labeling - Dose form - Federal med laws control: - Medication sales and distribution - Testing

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- Naming - Labeling - The use of controlled substances State and Local Regulations: - State and local laws conform to federal legislation but often add controls. - Local government regulates the use of tobacco and alcohol. Health Care Institutions and Med Laws: - Healthcare agencies establish individual policies to meet federal, state, and local regulations, but they are usually more restrictive than governmental controls (e.g. automatic discontinuation of narcotics after a set number of days) - Factors that influence these policies: - The size of the agency - The services it provides - The professional personnel it employs Med Regs and Nursing Practice: - State Nursing Practice Acts (NPAs) define the scope of practice for nurses and are purposefully broad so a nurse’s professional responsibilities aren’t limited. - Healthcare agencies can interpret specific actions under NPAs, but they can’t modify, expand, or restrict the intent of the act. - A nurse is responsible for following legal provisions when administering controlled substances; violations are punishable by fines, imprisonment, and loss of licensure.

Pharmacological Concepts - Med Names: - Chemical name = an exact description of its composition and molecular structure (rarely used in clinical practice) - E.g. N-(4-hydroxyphenyl)ethanamide - Generic name = name given by the drug manufacturer with the United States Adopted Names (USAN) Council approval. - E.g. (cont’d) - Acetaminophen - Trade/Brand or proprietary name = name under which a manufacturer markets a med; has the symbol (™) - E.g. (cont’d) - Tylenol - Be careful to obtain the exact name and spelling for each med you administer to your patients. - Because similarities in med names are a common cause of med errors, the Institute of Safe Medication Procedures (ISMP) publishes a list of medications that are frequently confused with one another. - Recommends use of the FDA-approved tall-man or mixed-case letters when possible (e.g., aMILordie versus amLODIPine)

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Classification: - Indicates the effect of a medication on a body system, the symptoms a medication relieves, or its desired effect. - Each class contains more than one med that’s used for the same type of health problem. - Beta-2 adrenergics contain more than 15 different meds - Some meds are in more than one class (e.g. aspirin is an analgesic, an antipyretic, and an anti inflammatory). Med Forms (tablets, capsules, elixirs, suppositories, etc.): - Med form determines its route of administration. - See Table 31.1 on page 591 for a full list

Pharmacokinetics as the Basis of Medication Actions - To be useful, a med must be taken, absorbed/distributed to cells, and alter physiological functions. - Absorption : - When medication molecules pass into the blood from the site of med admin - Factors that influence absorption: - Route of admin: - Each route has a different rate of absorption. - Meds that absorb slowly: - Meds on the skin - Because of the physical makeup of the skin (protective barrier) - Meds administered orally - Because meds have to pass through the GI tract - Meds that absorb quickly: - Meds placed on mucous membranes/respiratory airways - These tissues contain many blood vessels - Intramuscular (IM) and subcutaneous - IM injections enters the bloodstream quicker than subcutaneous injections - Intravenous (IV) - the most rapid absorption

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Meds are immediately available when they enter the systemic circulation

Dissolvability - The ability of an oral med to dissolve depends largely on its form or preparation. - State of matter: Solutions/suspensions (already in a liquid state) are absorbed more readily than tablets/capsules. - Acid/base: Acidic meds pass through the gastric mucosa rapidly. Meds that are basic aren’t absorbed before reaching the small intestine. Blood circulation to the site of admin/vascularity - The richer the blood supply, the faster a med is absorbed. Body surface area (BSA) - The larger the surface area, the faster the absorption rate. - Most meds are absorbed in the small intestine rather than the stomach because of the increased surface area. Lipid solubility of medication - Highly lipid-soluble meds cross the lipid bilayer of the cell membrane more easily and are absorbed more quickly than less lipid-soluble meds. - Some oral meds are absorbed more easily with meals because food changes the structure of a med and sometimes impairs its absorption. - When some meds are administered together, they interfere with one another, impairing the absorption of both medications. - You need to understand med pharmacokinetics, a patient’s health history, physical exam data, and knowledge gained through daily patient interactions to enact safe med administration.

Distribution: - Factors that affect distribution: - Circulation - How fast a med reaches a site depends on the vascularity of the various tissues or organs.

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Conditions that limit blood flow/blood perfusion inhibit the distribution of the med (e.g. HF) Membrane Permeability - Refers to the ability of a med to pass through tissues/membranes to enter target cells - Med must pass through all of the tissues and biological membranes of the organ. - Some membranes serve as barriers to passage of meds (e.g. blood-brain barrier) - Therefore, CNS infections often require treatment with antibiotics injected directly into the subarachnoid space in the spinal cord. - Some older adults experience adverse effects like confusion because of the change in the permeability of the blood-brain barrier (easier passage of fat-soluble meds) Protein Binding - The degree to which meds bind to serum proteins such as albumin affect their distribution. - Most meds partially bind to albumin, reducing its potency. The unbound part of the med is its active form. - Older adults/patients with liver disease or malnutrition have a decreased level of albumin in the bloodstream. - They are at risk for an increase in med activity, toxicity, or both.

Metabolism - After a med reaches its site of action, it’s broken down by enzymes into a less active or an inactive form that’s easier to excrete (biotransformation) - Occurs within the liver (although the lungs, kidneys, blood, and intestines also metabolize meds); especially important because its specialized structure oxidizes and transforms many toxic substances, degrading the harmful chemicals before they become distributed to the tissues. - If a decrease in liver function occurs, a med is usually eliminated more slowly, resulting in its accumulation. Patients are at risk for med toxicity if organs that metabolize meds aren’t functions correctly.

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Excretion - The chemical makeup of a medication determines the organ of excretion. - Gaseous/volatile compounds (NO and alcohol) exit through the lungs. - Deep breathing/coughing after surgery to eliminate anesthetic gases. - Exocrine glands excrete lipid-soluble meds - When meds exit through sweat glands, the skin often becomes irritated. - If med is excreted through the mammary glands, a nursing infant is at risk of ingestion of the chemicals (always check if a med is safe enough for breastfeeding mamas) - Meds that enter the hepatic circulation are broken down by the liver and excreted into the bile. After the chemical enters the intestines through the biliary tract, the intestines resorb them. - Factors that increase peristalsis (e.g. laxatives and enemas) accelerate med excretion through the feces, whereas factors that slow peristalsis (e.g. inactivity and improper diet) often prolong the effects of a med. - Kidneys are the main organ for med excretion. - Some meds escape extensive metabolism and exit unchanged in the urine. - Others undergo biotransformation in the liver before the kidneys excrete them. - Maintenance of adequate fluid intake (50 mL/kg/hr) promotes proper elimination of medications for the average adult. - If a patient’s renal function declines, the kidneys can’t adequately excrete meds, thus the risk of medication toxicity increases. HCPs need to reduce the doses for such patients. As renal function and liver function decrease, the risk for med toxicity increases. Types of medication actions - Patients don’t always respond in the same way to each successive dose of a med. Sometimes the same med causes very different responses in different patients (patient-centered care). - Therapeutic Effects: - The expected or predicted physiological response caused by a medication. - Some meds have more than one therapeutic effect. - Knowing the desired effect for each med allows you to provide patient education and accurately evaluate the desired effect of a med.

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Adverse Effects: - Undesired, unintended, and often unpredictable responses to a med. - Mild to severe; immediate to gradual - Patients most at risk for adverse med reactions include: - The very young and older adults - Pregnant women - Patients taking multiple meds - Patients who are extremely underweight/overweight - Patients with renal or liver disease. - Be alert and assess for unusual individual responses to meds, especially with newly prescribed meds. Most patients remain on meds with mild adverse effects; however, if they’re not tolerated or potentially harmful, stop giving the med immediately. - Side Effects: - A predictable and often unavoidable adverse effect produced at a usual therapeutic dose. - Most common: anorexia, nausea, vomiting, constipation, drowisness, and diarrhea. - Toxic Effects: - Often develop after prolonged intake of a med or when a med accumulates in the blood because of impaired metabolism or excretion. - Antidotes are available to treat specific types of med toxicity (naloxone for opioids) - Idiosyncratic Reactions: - Unpredictable effects in which a patient overreacts or underreacts to a med or has a reaction different from normal. - It’s not possible to predict whether a patient will have an idiosyncratic reaction or not to a med. - Allergic Reactions: - Unpredictable responses to a med in which patients become immunologically sensitized to the initial dose of medication, and with repeated administration, the patient develops an allergic response to it, its chemical preservatives, or a metabolite. - A patient’s med allergic reaction symptoms vary, depending on the individual and the med. - Make sure to ask if they have any medication allergies or if they are wearing a identification bracelet or medal that will alert you to their allergy. - Medication Interactions: - When one medication modifies the action of another; increases/decreases the action of others or alters the way another med is absorbed, metabolized, or eliminated from the body.

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Synergistic effect = their combined effect is greater than the effect of the meds when given separately (e.g. alcohol and antidepressants) - Sometimes a med interaction is desired to create a beneficial effect (HBP patients take diuretics and vasodilators to control their BP) Medication Tolerance and Dependence - Tolerance develops over time; when patients need more med to achieve the same therapeutic effect. - Includes opium alkaloids (e.g. morphine), nitrates, and ethyl alcohol - Dependence: - Two types: - Psychological dependence = a patient desires the med for a benefit other than the intended effect. - Physical dependence = a physiological adaptation to a med that manifests by intense physical disturbance when the med is withdrawn. - Nurses and other HCPs play an important role in the care of patients with drug addiction. Timing of medication dose responses - Medications are ordered at various times, depending on when their response begins, becomes most intense, and ceases. - Minimum effective concentration (MEC) = the plasma level of a medication below which the effect of a medication doesn’t occur. - Goal is to achieve a constant blood level between the toxic concentration and the MEC. - When a med is administered repeatedly, its serum level fluctuates between doses. - Highest level = peak concentration - After reaching its peak, the serum concentration of the medication falls progressively. - With IV infusions, the peak concentration occurs quickly, but the serum level also begins to fall immediately. - Lowest level = trough concentration - The time it takes for a medication to reach its peak concentration varies, depending on the pharmacokinetics of the med. - All meds have a biological half-life, which is the time it takes for excretion processes to lower the serum med concentration by half.

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To maintain a therapeutic plateau, a patient needs to receive regular fixed doses. - ATC (around the clock) - after an initial dose, the patient receives each successive dose when the previous dose reaches its half-life. - Terms to also know: - Duration of action: Length of time during which a medication is present in a concentration great enough to produce a therapeutic effect. - Onset of medication action: Period of time it takes after you administer a medication for it to produce a therapeutic effect Healthcare agencies usually set med admin schedules and determine whether meds are time critical; however, you can change this schedule based on your knowledge about a medication. - Meds that are time critical most likely cause harm or have subtherapeutic effects if they aren’t administered on time (30 minutes before or after the scheduled dose). When you teach patients about dosage schedules, use familiar language.

Routes of administration - Oral Routes: - Sublingual (under the tongue) - Instruct patients to not swallow or drink anything until the med is completely dissolved. - Buccal (cheek) - Instruct to alternate cheeks with each subsequent dose to avoid mucosal irritation. Warn patients to not check or swallow the med or to take any liquids with it. - Parenteral Routes (injections): - Four major sites of injection - Intradermal (ID) - just under the epidermis - Subcutaneous - tissues under the dermis - Intramuscular (IM) - muscle - Intravenous (IV) - vein - Other sites: - Epidural - epidural space via a catheter; used for admin of regional analgesia for surgical procedures. - Intrathecal - subarachnoid space or one of the ventricles of the brain via a catheter; often for a long-term treatment - Intraosseous (IO) - bone marrow; used in infants/toddlers who have poor IV access or when an emergency arises or when IV access is impossible. - Intraperitoneal - peritoneal cavity; chemotherapeutic agents, insulin, and antibiotics - Intrapleural - pleural space; chemotherapeutic agents

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Pleurodesis = instill meds to help resolve persistent pleural effusion to promote adhesion between the visceral and parietal pleura Intraarterial - into arteries; common in patients who have arterial clots and received clot-busting agents.

Topical Route: - Examples: - Transdermal patch or disk - Painting or spreading on skin - Applying moist dressings - Soaking body parts in a solution - Giving medicated baths - Topicals on the Mucosa in these ways: - Direct application of a liquid or ointment (gargling) - Insertion of a medication into a body cavity (suppository) - Instillation of fluid into a body cavity (eardrops) - Irrigation of a body cavity (flushing eye) - Spraying a med into a body cavity (nasal spray) Inhalation Route: - Through the nasal and oral passages or endotracheal or tracheostomy tubes. - Readily absorbed and work rapidly Intraocular Route: - Inserting a medication similar to a contact lens into a patient’s eye

Systems of medication measurements - Metric system - Household measurements - Solutions NURSING KNOWLEDGE BASE Clinical calculations - See Clinical Math videos at the bottom of PNP canvas page; ignore this section - Be careful with pediatric doses; a small med error could have drastic effects - Ped doses are usually smaller than adults (e.g. adults dose of tylenol= 500 mg; pediatric doses = at least 80 mg) - Ped doses are based on mg/kg Health care provider’s role - A physician, nurse practitioner, or PA prescribes meds by writing an order on a form in a patient’s medical record, in an order book, or on a legal prescription pad.

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Sometimes a health care provider orders a medication by telephone or by talking to a nurse in person. - An order for a medication or medical treatment made over the telephone is called a telephone order. If the order is given verbally to the nurse, it is called a verbal order. When a verbal or telephone order is received, the nurse who took the order writes the complete order or enters it into a computer, reads it back, and receives confirmation from the health care provider to confirm accuracy. The nurse indicates the time and the name of the health care provider who gave the order, signs it, and follows agency policy to indicate that it was read back. The health care provider countersigns the order later, usually within 24 hours after giving it.

Types of orders in acute care agencies - A med can’t be given to a patient w/o a HCP order. - The frequency and urgency of med admin forms the basis of med orders. - Some conditions change the status of a patient’s med orders. - Standing Orders or Routine Med Orders: - Carried out until the HCP cancels it by another order or a prescribed number of days elapses. - E.g. Tetracycline 500 PO q6h (every 6 hours) - Prn Orders: - Given only when a patient requires it. - E.g morphine sulfate 2 mg IV q2h prn for incisional pain - Indicates that the patient needs to wait at least 2 hours between doses and can take the med if experiencing pain at the incision. - Need to document assessment findings (to show why the patient needs the med) and time of admin - Frequently evaluate the effectiveness of the med and record evaluation data appropriately. - Unclear orders for prn meds that include a range (morphine sulfate 5-10mg every 4-6 hours) are a source of med errors. - Ensure that the order follows agency policy - An example of a safer range order is to increase morphine dosage 50% to 100% if pain is moderate to severe based on the use of the agency pain scale. - When multiple prn meds...