Final answer:
The next step after an AED detects ventricular fibrillation is to follow the AED prompts, which include pressing the shock button when instructed, ensuring that everyone stands clear of the patient during the shock delivery.
Step-by-step explanation:
When an automated external defibrillator (AED) detects ventricular fibrillation, the next step is to follow the AED prompts. These devices provide verbal instructions and will lead the rescuer through the necessary steps, which typically involve ensuring that no one is touching the patient, then pressing the device's shock button to deliver the shock. It is imperative to stand clear of the person while the shock is administered to avoid any person receiving the unintended shock. The AED's automatic diagnosis and instructions are crucial in the critical first few minutes of a cardiac emergency.