Cardiac Nursing Medications Quiz for Drug Knowledge

Amiodarone is classified as a Class III antidysrhythmic agent used in unstable ventricular dysrhythmias. It prolongs phase 3 repolarization by blocking potassium channels, increasing refractory periods. This stabilizes cardiac electrical activity and reduces abnormal ventricular firing. It is commonly administered in pulseless ventricular tachycardia or ventricular fibrillation, improving survival rates when defibrillation alone is insufficient.

Atropine is an anticholinergic drug that blocks muscarinic acetylcholine receptors. In bradycardia, excessive vagal tone slows sinoatrial node firing. Atropine inhibits parasympathetic influence, increasing heart rate and improving cardiac output. It is particularly effective in symptomatic bradycardia where hypotension or altered mental status occurs due to reduced perfusion.

Diazepam is a benzodiazepine that enhances GABA activity at inhibitory synapses. By increasing chloride ion influx, it suppresses neuronal excitability. This makes it effective for seizure control, alcohol withdrawal, muscle spasm, and acute agitation. Its rapid onset allows prompt central nervous system depression during emergency seizure management.

Enoxaparin is a low molecular weight anticoagulant that enhances antithrombin III activity. It inhibits factor Xa, reducing thrombin formation and clot propagation. In deep vein thrombosis, preventing clot enlargement lowers the risk of pulmonary embolism. Its predictable pharmacokinetics allow weight-based dosing without continuous laboratory monitoring.

Furosemide is a loop diuretic that inhibits sodium and chloride reabsorption in the ascending loop of Henle. This increases urine output and reduces circulating blood volume. In edema related to heart failure, decreasing preload alleviates pulmonary congestion and peripheral swelling, improving respiratory and cardiovascular efficiency.

Magnesium sulfate stabilizes cardiac membranes and suppresses neuromuscular transmission. In eclampsia, it prevents recurrent seizures by reducing central nervous system irritability. It also treats torsades de pointes by shortening QT interval abnormalities. Its dual neuromuscular and cardiac effects make it vital in obstetric and cardiac emergencies.

Nitroglycerin is a vasodilator that converts to nitric oxide, relaxing vascular smooth muscle. Venous dilation reduces preload and myocardial oxygen demand. Coronary artery dilation improves oxygen supply. This supply-demand balance relieves ischemic chest pain in angina and improves symptoms of acute heart failure.

Norepinephrine is a potent alpha-adrenergic agonist with some beta-1 activity. In shock states, systemic vasodilation causes severe hypotension. Norepinephrine increases systemic vascular resistance and modestly improves cardiac output, restoring mean arterial pressure and organ perfusion in septic or distributive shock.

Lisinopril is an ACE inhibitor that blocks conversion of angiotensin I to angiotensin II. This reduces vasoconstriction and aldosterone secretion, lowering blood pressure and decreasing fluid retention. In heart failure, afterload reduction improves cardiac output and reduces long-term ventricular remodeling.

Adenosine is an antidysrhythmic medication used primarily for stable supraventricular tachycardia. It slows conduction through the atrioventricular node, temporarily blocking electrical impulses. This interruption can reset abnormal reentrant circuits causing narrow complex tachycardia. Because of its extremely short half-life of less than 10 seconds, it acts rapidly and is ideal for acute rhythm conversion in hemodynamically stable patients.

Diltiazem is a calcium channel blocker that inhibits L-type calcium channels in cardiac tissue. This slows atrioventricular nodal conduction and reduces ventricular response in atrial fibrillation. By decreasing myocardial oxygen demand and stabilizing rhythm, it is effective in rate control strategies for supraventricular dysrhythmias.

Dobutamine is a beta-1 adrenergic agonist classified as an inotrope. It increases myocardial contractility, stroke volume, and cardiac output. In cardiogenic shock, reduced pump function causes hypotension and poor perfusion. Dobutamine improves forward blood flow without significantly increasing systemic vascular resistance, making it valuable in acute heart failure states.

Epinephrine stimulates both alpha and beta adrenergic receptors. In anaphylaxis, it reverses bronchoconstriction through beta-2 activation and raises blood pressure via alpha-mediated vasoconstriction. It also improves cardiac output through beta-1 stimulation. These combined effects rapidly counteract life-threatening airway swelling and circulatory collapse.

Esmolol is a short-acting beta-1 selective blocker used for rapid rate control in atrial flutter. By reducing sympathetic stimulation, it slows atrioventricular conduction and decreases heart rate. Its half-life of approximately nine minutes allows tight titration in acute care settings, minimizing prolonged hypotension risk.

Milrinone is a phosphodiesterase-3 inhibitor categorized as an inotrope. It increases intracellular cyclic AMP, enhancing myocardial contractility and causing vasodilation. In decompensated heart failure, this dual action improves stroke volume while reducing afterload, thereby optimizing cardiac performance and tissue perfusion.