MARYVILLE UNIVERSITY NURS 615 LATEST SET EXAM 2025

MARYVILLE UNIVERSITY NURS 615 LATEST SET EXAM 2025 Clinical Judgement - -Conclusion/opinion at which a nurse arrives following a process of observation, reflection, & analysis of observable or available information or data. *must gather data to make diagnosis, must have diagnosis to select and start treatment WHO 6-Step Model of Rational Prescribing - - 1. Define patient's problem (diagnose) 2. Specify the therapeutic objective (goal) 3. Choose treatment 4. Start treatment 5. Educate the patient 6. Monitor the effectiveness Criteria for choosing an effective drug I Can Prescribe A Drug" Mnemonic - - I=indication C=contraindication P=precautions C=cost/compliance E=efficacy A=adverse effects D=dose/duration/direction Role of FDA - -Ensures the safety, efficacy, and security of human and veterinary drugs, biological products, and medical devices. As well as food, cosmetics, and products that emit radiation. What is the role of the FDA in regard to supplements and vitamins? - -Does NOT protect or ensure the safety of supplements and vitamins. They have certain rules, but they aren't as stringent like they are for drugs. What can St. John's wort interact with? - -SSRI, CNS drugs, MAOI, SSNRI, steroids, caffeine, and anticoagulants. Off-label prescribing - -medication is being used in a manner not specified in the FDAs approved packaging label/insert. *different route, dose, or indication Pharmacotherapeutics - -study of therapeutic uses and effects of drugs. Beneficial and adverse drug reactions. NURS 615 NURS 615 Pharmacodynamics - -what the drug does to the body Agonist - -binds to a receptor & produces a response/stimulates (full activation) Antagonist - -Binds & blocks activity (no activation) Can a drug be an agonist and antagonist? - -Yes. In this case, they do both actions to have less activation, versus full or no activation. Pharmacokinetics - -what the body does to the drug (ADME) What is ADME in pharmacokinetics? - -absorption, distribution, metabolism, excretion Absorption - -first step, occurs after medication administration What does absorption depend on? - -routes of administration, pH and membrane penetration What percentage of rectal drugs go through first-pass metabolism? - -50% Membrane penetration involves what? - -lipid solubility and ionization How does pH affect absorption? - -If the pH of the stomach is altered, in oral medication administration, the medication can be absorbed too soon or not soon enough. Why can't you crush enteric coated medications? - -This interferes with absorption, it will not absorb where intended. Ionization - -the charge of the molecule/drug. Ionized = charged (polar) non-ionized = uncharged (non-polar) Lipophilic - -*Lipid loving, uncharged (non-polar/non-ionized), small in size. *crosses membranes more easily than hydrophilic How do lipophilic drugs cross membranes? - -Passive diffusion. Most cell membranes are lipophilic, making it easier for lipophilic drugs to cross. Passive diffusion - -the movement of drugs from an area of higher concentration to lower concentration (moves across a concentration gradient) What is the volume of distribution for lipophilic drugs? - -Lipophilic drugs have a high volume of distribution and a long duration of action. Hydrophilic - -*Water loving, charged (ionized/polar), large in size *more difficultly with crossing membranes NURS 615 NURS 615 How do hydrophilic drugs cross membranes? - -Active transport or filtration What is the volume of distribution for hydrophilic drugs? - -Lower volume of distribution and shorter duration of action Factors affecting absorption - -bioavailability & first-pass metabolism Bioavailabity - -fraction of drug that reaches the systemic circulation. Depends on solubility, chemical structure, size, polarity, and pre-systemic biotransformation *important for drugs with narrow therapeutic ranges or SR meds First-pass metabolism - -*only oral and 50% of rectal drugs *medication must go through intestinal tract, then the portal vein to the liver. Once in the liver, part of the drug is metabolized, and the remainder enters systemic circulation. Distribution - -occurs after absorption; transport of drug to its site of action Volume of distribution depends on.... - -membrane penetration and protein binding Protein binding & drugs - -protein binding is reversible! *if drug is bound to protein it isn't *free* or available for action. How does protein binding prolong drug action - -the protein will eventually release the drug, which then makes it "free" or available for action. The previous free drug has likely been excreted, thus extending drug action. What are considered high protein bound drugs - -when > 90% of the drug binds to proteins Do lipophilic or hydrophilic drugs distribute more easily? - -Lipophilic drugs have higher levels of distribution, so they will spread throughout the body more easily Where do hydrophilic drugs prefer to stay? - -in areas of high water concentration and systemic circulation How does pregnancy affect the volume of distribution for hydrophilic drugs? - -Volume of distribution increases because of increased TBW and extracellular volume Barriers to distribution - -Blood brain barrier, placental barrier, and alterations in protein binding. What is the purpose of the BBB and placental barrier? - -to protect the brain/fetus from toxins. *tightly bound, difficult for substances to cross, usually crossed through simple diffusion NURS 615 NURS 615 Simple diffusion - -diffusion of small, uncharged, or hydrophobic molecules from an area of high concentration to an area of low concentration across the cell membrane How can the BBB or placental barrier be altered and become less effective? - -Age, HTN, radiation, trauma, microwaves, and infection Hypoalbuminemia and drug distribution - -results in decreased protein binding. This can result in toxicity, the med wont get the correct length of action, and steady state can't be maintained. What happens when a patient takes multiple protein binding drugs? - -Drugs compete for proteins, results in increased free drug for both drugs. More free drug=risk for toxicity Metabolism - -*aka biotransformation *process of chemically changing a drug to a different compound called a metabolite. *process increases water solubility and decreases lipid solubility for excretion Why do drugs need to be metabolized to increase water solubility? - -This helps the body excrete the drug. Phase 1 metabolic reactions - -*oxidation/reduction reactions *modifies chemical structure by adding O2 **CYP450 CPY450 - -*most significant oxidation enzyme. Responsible for oxidation in drug metabolism (inactivates them and makes them more water soluble) *each drug has a specific CYP450 enzyme that metabolizes it CYP450 and drug interactions - -*responsible for a lot of drug interactions because some drugs or other substance can affect the enzymes CYP450 inhibitors - -inhibit production of the enzyme, results in a higher amount of active drug in system = prolonged duration of action, toxicity *ex = grapefruit juice inhibits CYP450 that metabolizes statins CYP450 inducers - -promotes enzyme production, resulting in increased metabolism = decreased efficacy, duration of action Phase 2 metabolic reactions - -conjugation/hydrolysis reactions Conjugation/hydrolysis reactions - -conjugate a drug to a large, polar (charged/hydrophilic) molecule to enhance drugs solubility in urine Prodrugs - -drugs that must be metabolized first to become active NURS 615 NURS 615 Barriers/factors affecting metabolism - -age, genetics (acetylation), disease (ex. liver diseases affect drug metabolism = increased risk of toxicity), diet, environment, and