Automated External Defibrillator (AED) Use
The AED is the link that converts a shockable rhythm into a perfusing rhythm, and its value depends on early use with minimal interruption of compressions. The AED analyzes the rhythm and advises a shock only for ventricular fibrillation and pulseless ventricular tachycardia; it will not shock asystole or a normal rhythm. A candidate must know the operational sequence: power on the AED, attach pads to the bare, dry chest, clear everyone while it analyzes, deliver a shock if advised, and immediately resume compressions.
Practical details and traps
- Pad placement: one pad on the upper right chest, one on the lower left side (or per the device diagram). Use pediatric pads or a pediatric attenuator for children under 8 years or under about 55 lb (25 kg) when available; if not available, use adult pads.
- Special situations: remove medication patches from the chest, dry a wet chest, and avoid placing pads directly over an implanted device (place them at least several inches away). For a hairy chest, shave or use a second set of pads if the device advises.
- Do not touch the patient during analysis or shock delivery-a classic trap is a rescuer continuing compressions during analysis.
- Resume compressions immediately after the shock; do not pause to check a pulse or rhythm right away.
- Water and metal: move the patient off a wet surface and away from standing water; avoid contact with metal that could conduct current.
Worked example: The AED advises "no shock." The correct action is to immediately resume CPR, beginning with compressions, and continue for about 2 minutes until the AED prompts another analysis. Do not remove the pads or stop resuscitation on the basis of one "no shock" message.
Rule of thumb: Analyze clear, shock clear, and get back on the chest the instant the shock is delivered.