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Cardiac arrest strikes immediately and without warning. Here are the signs:

• Sudden loss of responsiveness. No response to gentle shaking.
• No normal breathing. The victim does not take a normal breath when you check for several seconds.
• No signs of circulation. No movement or coughing.

If cardiac arrest occurs, call 9-1-1 and begin CPR immediately. If an automated external defibrillator (AED) is available and someone trained to use it is nearby, involve them.