Video courtesy of The University of Arizona/Sarver Heart Center
AED (automated external defibrillator) Assisted CPR
The most common reason for a sudden cardiac arrest is a ventricular fibrillation, which is an extreme disruption of the heart's ability to beat and pump blood. While CPR can temporarily maintain a patient's blood and oxygen flow, use of an AED — short for automated external defibrillator — is often the only way to permanently restore the heartbeat.
Rescue intervention with an AED is, says Sayre, "akin to rebooting your computer when it crashes." However, in order to be effective, an AED must be used within three to five minutes of the cardiac arrest.
To increase the availability and use of AEDs by the public, the devices are frequently installed alongside the wall-mounted first aid kits and fire extinguishers located in many municipal and commercial buildings, such as airports, shopping malls and stadiums.
A common misperception about AEDs is that they are for use only by professional emergency responders. In fact, the opposite is true. Paramedics arrive at emergency scenes with their own fibrillation equipment. The AEDs installed in public places are very similar to, but are not the same as, the devices found in emergency rooms and ambulances, and used with great fanfare on TV medical dramas.
AEDs, which provide voice instructions and visual prompts to the bystander who is providing aid, come with pads and wires that attach to a victim's bare chest. The device analyzes the person's heart activity to determine when and if an electric shock should be delivered.
Dr. Gordon Ewy, director of the University of Arizona's Sarver Heart Center (he appears in the video, above, and helped create the hands-only CPR guidelines), reminds that AEDs are to be used in conjunction with chest compressions, not instead of them.
In a typical cardiac arrest scenario where an AED is available:
- Call 911 and retrieve the AED, or ask someone else to.
- Perform deep chest compressions until the AED is activated and, if determined suitable, administers a shock.
- Continue chest compressions (at a rate of 100 a minute for two minutes) until the AED performs another assessment, recommends another shock, the patient is revived or medical assistance arrives.
Helpful Hint: Even with the assistance of an AED, performing CPR is hard work for a rescuer. If other bystanders are available to help, take turns performing chest compressions, perhaps switching off after each minute of 100 compressions.