Final answer:
In a cardiac emergency, call 911 and get an AED when someone is experiencing a heart attack or has a sudden cardiac arrest. The AED is a portable device that delivers a shock to the person's heart to correct abnormal heart rhythm. It is important to provide prompt medical help.
Step-by-step explanation:
In a cardiac emergency, you should call 911 or tell someone to get the Automated External Defibrillator (AED) when someone is experiencing a heart attack or has a sudden cardiac arrest. It is important to call for professional help immediately so that medical personnel can provide appropriate treatment as soon as possible. The AED is a portable electronic device that delivers a shock to the person's heart to correct abnormal heart rhythm. It is commonly found in many public places and is designed to be used by laypersons.
If you are alone during the emergency, call 911 and then retrieve the AED yourself if it is available nearby. Follow the device's verbal instructions for use while waiting for professional help to arrive. It is recommended to administer CPR (cardiopulmonary resuscitation) in many cases before using the AED.