When should a lifeguard use an automated external defibrillator (AED)?

A lifeguard should use an automated external defibrillator (AED) when the victim is unresponsive and not breathing because this indicates a potential cardiac arrest situation. In such circumstances, prompt action is crucial. The AED assesses the heart rhythm and can deliver a shock if necessary, which can significantly increase the chances of survival by restoring a normal heartbeat.

Using an AED on a conscious victim is inappropriate since they do not require defibrillation, which is only needed in cases of cardiac arrest. Similarly, a victim showing signs of distress may still be breathing and responsive, indicating they might not need immediate defibrillation. Waiting for medical personnel to arrive before using an AED can delay critical care in a situation where every second counts; immediate action improves survival outcomes. Therefore, the use of an AED should be initiated as soon as it is confirmed that the victim is unresponsive and not breathing.