A nurse is preparing an in-service presentation about the use of automated external defibrillators (AEDs). Which of the following instructions should the nurse include in the teaching?

A. "Perform CPR while the AED is analyzing": The AED must analyze the heart rhythm without interference. Performing CPR during analysis can prevent the device from accurately detecting a shockable rhythm, so the nurse should instruct to pause CPR while the AED evaluates the client. B. "Use an AED for a client who has atrial fibrillation.": AEDs are not indicated for atrial fibrillation unless it degenerates into a pulseless ventricular arrhythmia. AEDs are designed for sudden cardiac arrest due to ventricular fibrillation or pulseless ventricular tachycardia, not for non-life-threatening arrhythmias. C. "Position the client on a flat surface.": Placing the client on a firm, flat surface ensures effective chest compressions and proper contact of AED pads with the chest. This positioning is critical for both CPR efficacy and accurate AED analysis. D. "Set the AED to 80 joules.": Modern AEDs are automatic and preprogrammed to deliver the appropriate energy level. Users should not manually set joules, as the device determines the correct shock dose for safety and effectiveness.