Nokea
When explaining how verapamil (Calan) produces its effects on the cardiovascular system, which of the following would the nurse integrate into the explanation? Select all that apply.
- A. Reduction in the release of renin
- B. Dilation of coronary arteries
- C. Dilation of peripheral arteries
- D. Slowed conduction through the SA and AV nodes
- E. Membrane-stabilizing effects
Correct Answer: B,C,D
Rationale: Verapamil (Calan) is a calcium channel blocker. These drugs inhibit the movement of calcium through channels across the myocardial cell membranes and vascular smooth muscle. Cardiac and vascular smooth muscle depends on the movement of calcium ions into the muscle cells through specific ion channels. When this movement is inhibited, the coronary and peripheral arteries dilate, thereby decreasing the force of cardiac contraction. This drug also reduces heart rate by slowing conduction through the SA and AV nodes.
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Administration with which of the following would increase serum concentrations of disopyramide? Select all that apply.
- A. Amiodarone
- B. Quinidine
- C. Rifampin
- D. Cimetidine
- E. Erythromycin
Correct Answer: B,E
Rationale: Increased serum disopyramide levels occur when quinidine or erythromycin is given with disopyramide. Amiodarone and cimetidine increase serum flecainide levels. Rifampin decreases serum disopyramide levels.
After teaching a group of nursing students about antiarrhythmics, the instructor determines that the teaching was successful when the students identify which of the following as a class IA antiarrhythmic? Select all that apply.
- A. Quinidine (Quinaglute)
- B. Lidocaine (Xylocaine)
- C. Propafenone (Rythmol)
- D. Disopyramide (Norpace)
- E. Flecainide (Tambocor)
Correct Answer: A,D
Rationale: Class IA antiarrhythmics include disopyramide and quinidine. Lidocaine is a class IB drug. Propafenone and flecainide are class IC drugs.
A nurse is reviewing a journal article about class IA antiarrhythmics. The article describes a drug that decreases depolarization and prolongs the refractory period. The nurse is most likely reading an article about which drug?
- A. Quinidine
- B. Lidocaine
- C. Disopyramide
- D. Flecainide
Correct Answer: C
Rationale: Disopyramide (Norpace) decreases depolarization of myocardial fibers, prolongs the refractory period, and increases the action potential duration of cardiac cells. Lidocaine (Xylocaine) decreases diastolic depolarization, decreases automaticity of ventricular cells, and raises the threshold of the ventricular myocardium. Quinidine depresses myocardial excitability or the ability of the myocardium to respond to an electrical stimulus. Flecainide (Tambocor) depresses fast sodium channels, decreases the height and rate of rise of action potentials, and slows conduction of all areas of the heart.
When evaluating a client who is receiving antiarrhythmic therapy, which of the following would the nurse interpret as an expected outcome? Select all that apply.
- A. No evidence of injury is seen.
- B. No evidence of infection is seen.
- C. Client is free of nausea.
- D. Client urinates adequately.
- E. Oral mucous membranes are intact and moist
Correct Answer: A,B,C,D,E
Rationale: Absence of injury, infection, and nausea, adequate renal function, and intact, moist oral mucous membranes are expected outcomes for antiarrhythmic therapy.
A nurse is preparing to administer an antiarrhythmic and identifies the drug as a class III potassium channel blocker. Which drug would the nurse be most likely to administer?
- A. Amiodarone
- B. Flecainide
- C. Mexiletine
- D. Propafenone
Correct Answer: A
Rationale: Amiodarone is a class III potassium channel blocker. Flecainide, mexiletine, and propafenone are class I sodium channel blockers.