In what circumstances would you NOT use an AED?

The choice to not use an AED in cases of trauma or drowning is grounded in the understanding that these situations may not involve a cardiac arrest that is amenable to defibrillation. While trauma and drowning can certainly lead to cardiac arrest, the immediate focus in these instances is on addressing the underlying cause of the collapse. In trauma cases, potential injuries may create additional complications when applying pads or analyzing heart rhythms. Similarly, in drowning incidents, resuscitation efforts should ideally prioritize airway management and ventilation before utilizing an AED, especially if the person is not yet in a treated cardiac arrest scenario.

In other scenarios, like when a patient has a pacemaker or during a seizure, it is generally still appropriate to use an AED. Pacemakers can often coexist with AED use without significant risk, and an AED can be applied once a seizure is resolved and the patient shows signs of cardiac arrest. If a patient is conscious, it is clear that they are not in a state requiring defibrillation, but this does not invalidate the use of an AED once they lose consciousness or if their heart rhythm demonstrates a shockable rhythm.