If a 75-year-old female struck by lightning is unresponsive and pulseless after five minutes of CPR, what should you do next?

In a situation where a 75-year-old female has been struck by lightning and is both unresponsive and pulseless after five minutes of CPR, the next appropriate action is to apply the AED while continuing chest compressions. This is critical because early defibrillation can significantly increase the chances of survival, especially in cases of sudden cardiac arrest where an underlying shockable rhythm may be present.

Using the AED as soon as it becomes available is essential, as it can deliver a shock to help restore a normal heart rhythm. Continuing compressions while the AED is prepared helps maintain blood circulation to vital organs, optimizing the patient's chances until defibrillation can occur.

While examining for entry and exit wounds may be necessary for thorough assessment after the initial management and resuscitation, it should not delay critical interventions like CPR and defibrillation. Similarly, stopping CPR to assess the patient is counterproductive since high-quality CPR should be continuous until advanced care takes over. Applying a mechanical CPR device is useful but might not be immediately feasible or available; the priority remains on utilizing the AED and continuing compressions to maximize the chances for a successful resuscitation.