Summary NR 293 Exam 3 Study Guide

NR 293 Exam 3 Study Guide • Alpha2-adrenergic receptor stimulators (agonists)/clonidine o Stimulate alpha2-adrenergic receptors in the brain o Decrease sympathetic outflow from the CNS, decrease norepinephrine production o Stimulates alpha2-adrenergi receptors, thus reducing renin o Examples: Clonidine (Catapres), Methyldopa (aldomet): used for pregnant women w/htn • Alpha1-blockers/”azosin,” o Block alpha1-adrenergic receptors o Management of severe heart failure (HF) when used with cardiac glycosides and diuretics o Some used to relieve symptoms of BPH- increase urinary flow rate o Example: “ Azosin” (doxazosin (Cardura) o Adverse Effects: ▪ Serious: hypotension (first dose) syncope ▪ Common: dizziness o Nursing implications: instruct pt. to lie down after taking first dose because they may become dizzy • Beta-blockers “olol”: First-line treatment for heart failure & HTN o Reduce BP by reducing heart rate through beta1 blockade (block receptors for norepinhrine) o Cause reduced secretion of renin o Long-term use causes reduced peripheral vascular resistance o Adverse Effects: orthostatic hypotension, bradycardia w/ reflex tachycardia, sexual dysfunction in men, possible hypoglycemia or hyperglycemia • Angiotensin-converting enzyme inhibitor, “pril” Captopril o Mechanism of Action: ▪ Inhibit angiotensin-converting enzyme, which is responsible for converting angiotensin I (through the action of renin) to angiotensin II ▪ Angiotensin II is a potent vasoconstrictor and causes aldosterone secretion from the adrenal glands ▪ Result in decreased systemic vascular resistance (afterload), vasodilation, and therefore decreased blood pressure o Indications: ▪ First-line treatment for heart failure & HTN ▪ HF (either alone or in combination with diuretics or other drugs) ▪ Slow progression of left ventricular hypertrophy after MI (cardio protective) ▪ Renal protective effects in patients with diabetes ▪ Captopril and lisinopril can be used if a patient has liver dysfunction, unlike other ACE inhibitors that are pro-drugs • *Pro-drugs are inactive in their administered form and must be metabolized in the liver to an active form so as to be effective o Adverse Effects: hyperkalemia & dry, nonproductive cough o Serious drug interaction: NSAIDs • Angiotensin II receptor blocker “sartan” losartan (Dovan) o Mechanism of Action: ▪ Allow angiotensin I to be converted to angiotensin II, but block the receptors that receive angiotensin II ▪ Block vasoconstriction and release of aldosterone ▪ Well tolerated, do not cause a dry cough ▪ Indications: first-line treatment for heart failure & HTN o Adverse Effects: URI, headache ▪ May cause occasional dizziness, inability to sleep, diarrhea • Calcium channel blockers: Amlodipine “dipine” verapamil (calan), diltiazem (cardizem) o Mechanism of Action: cause smooth muscle relaxation by blocking the binding of calcium to its receptors, preventing muscle contraction o Adverse effect: constipation ▪ High-fiber diet with plenty of fluids will help prevent constipation o Indications: hypertension ▪ Angina- ch. 23 • Ischemia: o Ischemic heart disease: Poor blood supply to the heart muscle (Atherosclerosis, Coronary artery disease) o Myocardial infarction (MI): Necrosis, or death, of cardiac tissue, disabling or fatal • Therapeutic Objectives o Minimize the frequency of attacks and decrease the duration and intensity of anginal pain o Improve the patient’s functional capacity o Prevent or delay the worst possible outcome: MI • Cardiac glycosides: Digoxin o Therapeutic level: between 0.5-2ng/mL o Digoxin doses are held and the prescriber notified if the apical pulse is 60 beats/minute o Negative chronotropic effect decreases HR o Digoxin immune Fab (Digifab) is the antidote for a severe digoxin overdose ▪ Required use of digitab when potassium level is above 5 mEq/L, severe sinus bradycardia that does not respond to cardiac pacing, or an overdose of more than 10 mg of digoxin. o Avoid bran muffins when taking digoxin o Hypokalemia increases the chance of digitalis toxicity • Class III drugs: Amiodarone (ch. 25) o Mechanism of action: prolonging action potential duration o Indications: ventricular dysrhythmias o Contraindication: hypersensitivity and bradycardia or AV block Adverse effects: FDA black box warning: pulmonary toxicity, hepatotoxicity arrhythmia worsening-sinus bradycardia, constipation, QT prolongation, hypotension, blue-gray coloring of the skin on the face, arms, and neck • Unclassified antidysrhythmics: Adenosine (Ch. 25) ▪ Slows conduction through the AV node ▪ Used to convert paroxysmal supraventricular tachycardia to sinus rhythm ▪ Very short half-life (less than 10 seconds) • Flush with 20cc of normal saline ▪ Only administered as fast IV push ▪ May cause asystole for a few seconds ▪ Adverse Effects • ALL antidysrhythmics can cause dysrhythmias! • Hypersensitivity reactions, nausea, vomiting, diarrhea, dizziness, blurred vision, headache ▪ Assessment • Obtain a thorough drug and medical history • Baseline BP, P, I&O, and cardiac rhythm • Measure serum potassium levels before initiating therapy • Conditions that may be contraindications for use of specific drugs • Potential drug interactions ▪ During therapy, • Monitor cardiac rhythm, heart rate, BP, general well-being, skin color, temperature, heart and lung sounds • Assess plasma drug levels as indicated • Monitor for toxic effects • Take medications as scheduled and not to skip doses or double up for missed doses • Contact their physician for instructions if a dose is missed • Notify health care provider of any worsening of dysrhythmia or toxic effects • Nitrates and nitrites: Nitroglycerin o Prototypical nitrate o Large first-pass effect with oral forms o Used for symptomatic treatment of ischemic heart conditions (angina) o IV form used for BP control in perioperative hypertension, treatment of HF, ischemic pain, pulmonary edema associated with acute MI, and hypertensive emergencies o Adverse effects: headaches ▪ Reflex tachycardia ▪ Postural hypotension ▪ Tolerance may develop o Tolerance ▪ Occurs in patients taking nitrates around the clock or with long-acting forms ▪ Prevent tolerance by removing patch at bedtime for 8 hours, then apply a new patch in the morning o Nitroglycerin ▪ Nursing implications: • If the chest pain is not relieved after one tablet, call 911 immediately. • Never to chew or swallow the sublingual form • Non-polyvinylchloride (non-PVC) plastic intravenous bags and tubing must be used when giving IV nitroglycerin • Burning sensation felt with sublingual forms indicates that the drug is still potent • Proper application of nitrate ointments and transdermal forms, including site rotation and removal of old medication before new dose is applied. • Instruct patients to take PRN nitrates at the first hint of anginal pain ▪ Antidysrhythmia patient implications: • Do not chew or crush ER meds • If GI distress occurs take the drug with food • Limit or avoid the use of caffeine Chapter 28 • Loop diuretics: furosemide (Lasix) o Mechanism of Action: ▪ Rapid onset of action and cause rapid diuresis ▪ Act directly on the ascending limb of the loop of Henle to inhibit chloride and sodium resorption ▪ Increase renal prostaglandins-dilation of blood vessels o Examples: ▪ Bumetanide (Bumex), furosemide (Lasix) o Indications: ▪ Edema associated with HF or hepatic or renal disease, HTN ▪ Hypercalcemia: increase renal excretion of calcium o Adverse effects: ▪ FDA warning: Fluid and electrolyte depletion ▪ Serious: severe hypokalemia, bone marrow suppression ▪ Common: dizziness, hypotension, hyperglycemia. • Osmotic diuretics: mannitol (Osmitrol) o Mechanism of Action/Drug Effects ▪ Intravenous infusion only, filter is required ▪ Works in the proximal tubule, no absorbable, producing an osmotic effect ▪ Pull water into the renal tubules from the surrounding tissues o Indications: reduces intracranial pressure, treatment of cerebral edema o Acute renal failure: early, oliguric phase o Adverse Effects: convulsions, thrombophlebitis, pulmonary congestion • Potassium-sparing diuretics: Spironolactone (Aldactone) o Also known as aldosterone-inhibiting diuretics o Mechanism of Action: ▪ Competitively bind to aldosterone receptors ▪ Block resorption of sodium and water ▪ Interfere with sodium-potassium exchange o Indications: hypertension, hyperadlosteronism o Adverse effects: hyperkalemia, GI cramping • Thiazides and thiazide-like diuretics: “ Thiazide” hydrochlorothiazide (HydroDIURIL) o Mechanism of Action: ▪ Inhibit tubular resorption of sodium, chloride, and potassium ▪ Dilate the arterioles by direct relaxation • Not be used if creatinine clearance is less than 30 to 50 mL/min (normal is 125 mL/min) o Indications: hypertension (first line for HTN) & edematous states o Interaction: digitalis (digoxin) o Adverse effects: hypokalemia, electrolyte imbalance, & bone marrow • Nursing Implication for all are the same: o Perform ▪ History and physical examination ▪ Baseline fluid volume status, I & O, serum electrolyte values, weight, and vital signs—especially postural BPs ▪ Monitor serum potassium levels during therapy o Instruct patients ▪ Take the medication in the morning: sleep pattern ▪ Change positions slowly ▪ Diet: fluid and electrolyte ▪ Maintain proper nutritional and fluid volume status ▪ Notify their primary care provider if nausea, vomiting, and/or diarrhea occurs ▪ S/s hypokalemia-muscle weakness, constipation, irregular pulse rate, and overall feeling of lethargy ▪ If having rapid heart rates or syncope -- hypotension or fluid loss ▪ Pt. with diabetes mellitus: monitor hemoglobin A1C level Chapter 27 (Antilipemic) • HMG-CoA reductase inhibitors “ Statin”: atorvastatin o First-line drug therapy for HLD o Inhibit HMG-CoA reductase, which is used by the liver to produce cholesterol-Lower the rate of cholesterol production o Example: pravastatin (Pravachol) o Interactions: ▪ Oral anticoagulants ▪ Drugs metabolized by CYP3A4 • Erythromycin, Azole antifungals, Verapamil, Diltiazem, HIV protease inhibitors, Amiodarone, Grapefruit juice o Adverse Effects: myopathy (muscle pain) ▪ Rhabdomyolysis (muscle injury), Due to this can have a mental status change leading into kidney failure • Bile acid sequestrants: Cholestyramine o Mechanism of action: ▪ Prevent resorption of bile acids from small intestine ▪ Bile acids are necessary for absorption of cholesterol o Adverse Effects: decrease in absorption, constipation, heartburn o Education Patient: mix powder with food or at least 4-6 ounces of fluid ▪ Other medications should be taken 1 hour before or 4 to 6 hours after meals to avoid interference with absorption • Niacin: niacin o Mechanism of action: increase activity of lipase, which breaks down lipids ▪ Effective in lowering triglyceride, total serum cholesterol, and LDL levels, increases HDL levels o Adverse Effects: hepatotoxicity, cutaneous flushing, pruritus, GI distress, hyperuricemia o Nursing implications: Small dose of aspirin or may be taken 30 minutes before niacin to minimize cutaneous flushing • Fibric acid derivatives and cholesterol absorption inhibitor (fibrates) o Mechanism of Action: believed to work by activating lipase, which breaks down cholesterol o Examples: gemfibrozil (Lopid), fenofibrate (Tricor) o Adverse Effects: diarrhea, myopathy, rhabdomyolysis, increased risk of gallstones, liver enzyme levels increase, abdominal discomfort, prolonged prothrombin time o Interactions: ▪ Oral anticoagulants and Statins (Risk for myopathy is increased) ▪ Laboratory test reactions: (lactate dehydrogenase level, Decreased H/H, wbc, Increased aPTT, and bilirubin level) • Nursing Implication for all of Chapter 27: o Monitor for liver dysfunction o Report abnormal/unusual bleeding or yellow discoloration of skin, report muscle pain immediately, & eat extra servings of raw veggies and fruit