Final answer:
The nursing priority when an AED advises a shock is to immediately administer the shock, as it can terminate a life-threatening arrhythmia and allow the heart to resume a normal rhythm.
Step-by-step explanation:
When a victim is found unconscious and an Automated External Defibrillator (AED) advises a shock, the nursing priority is to administer the shock. AEDs are sophisticated yet user-friendly devices that can diagnose potentially life-threatening cardiac arrhythmias, such as ventricular fibrillation and pulseless ventricular tachycardia. Upon diagnosis, the AED will advise the rescuer to deliver a shock. This shock is imperative to terminate the arrhythmia, intending to allow the heart's natural pacemaker to re-establish a normal rhythm. After administering the shock, the nurse should follow up with CPR until emergency medical services take over or the victim shows signs of recovery.