An automated external defibrillator (AED) is a small, lightweight device used by both professionals and laypersons to assess heart rhythm by computer analysis. Using voice and visual prompts, it administers an electric shock, if necessary, to restore a normal rhythm in patients with sudden cardiac arrest. A shock is administered only if the rhythm detected is VF or pulseless VT. Automated external defibrillators are available from medical device manufacturers and local pharmacies. Although the AEDs all operate in basically the same way, external features vary from model to model. Be sure to follow the manufacturer’s recommendations.

Indications:Ventricular fibrillation or pulseless VT in adults, children, and infants.

Dose: The AED will automatically select the energy dose for each defibrillation. Some devices are equipped with pediatric systems that include a pad–cable system or a key to reduce the delivered energy to a suitable dose for children.

Procedure

1. Verify that the patient is in cardiac arrest, with no pulse or respiration. Have someone provide CPR while the AED is obtained and placed next to the patient.
2. Power on the AED. Follow the voice prompts and visual messages.
3. Open the package of adhesive electrode pads and attach pads to the patient’s bare chest.
4. Use adult pads for an adult and child pads for a child. If there are no child pads available, you may use adult pads on a child, but be sure the pads do not touch.
5. Attach one pad to the right sternal border (superior-anterior right chest) and place the second pad over the left apex (inferior-lateral left chest). Alternatively, follow the diagrams on each of the AED electrodes.
6. Connect the pad cables to the AED.
7. Clear the patient and stop CPR. Remove oxygen, if applicable.
8. The AED may automatically analyze the patient’s rhythm or may be equipped with an “analyze” button.
9. If a shock is advised, say, “I’m going to shock on three. One, I’m clear; two, you’re clear; three, everybody’s clear.” Perform a visual sweep to ensure rescue personnel are not touching the patient or equipment. Remove oxygen, if applicable. Press the shock button.
10. Once the shock is delivered, continue CPR beginning with chest compression.
11. After about 2 minutes of CPR, the AED will prompt you with further verbal and visual cues.

Clinical Tip: A fully automated AED analyzes the rhythm and delivers a shock, if one is indicated, without operator intervention once the pads are applied to the patient.

Clinical Tip: A semiautomated AED analyzes the rhythm and tells the operator that a shock is indicated. If it is, the operator initiates the shock by pushing the shock button.