Facts on File Encyclopedia of Health and Medicine

Cardiac Arrest

Cardiac arrest—any circumstance in which the
HEARTstops beating—is immediately life-threaten-
ing. The BRAINcan survive only four to six min-
utes without oxygen, after which brain cells begin
to die. Their loss is permanent. After 10 minutes
without oxygen brain death occurs. The American
Heart Association (AHA) identifies four actions,
called the cardiac chain of survival, as crucial:

1. Call 911 to summon emergency medical aid.


2. Start CARDIOPULMONARY RESUSCITATION (CPR) to
   restore circulation.


3. Defibrillate (shock) the heart to restore func-
   tional electrical activity.


4. Get the person to a hospital for advanced car-
   diac life support care.

The first person to come upon a person who is
in cardiac arrest sets this chain in motion and may
perform the first two or three actions, depending
on whether there is an AUTOMATED EXTERNAL DEFIB-
RILLATOR(AED) at the scene. The speed with which
the first responder acts establishes the likelihood
of survival. For optimal outcome, CPR must begin
within four minutes of when the heart stops. A
person who reaches step 4 within 30 minutes has
the highest chance for survival.

COMMON CAUSES OF CARDIAC ARREST
ANAPHYLAXIS ASPHYXIATION
diabetic SHOCK drowning
ELECTROCUTION HEART ATTACK
hemorrhage MULTIPLE TRAUMA
poisoning STROKE

cardiopulmonary resuscitation (CPR) Emer-
gency efforts to restore the function of the HEART

and circulation of BLOODthrough the body. CPR

combines RESCUE BREATHINGwith cardiac compres-

sions. The first person to respond to a situation

that requires CPR must first call 911 to summon

emergency medical aid. Do not stop CPR once

under way, unless the person begins to COUGHor

breath independently or until trained medical per-

sonnel arrive to take over.

Essential responder personal protection items

include latex or latex-style gloves and a resuscita-

tion shield. To perform CPR:

1. Listen or feel for BREATHINGand check for PULSE.
   If absent, continue with CPR.


2. Place the person on his or her back with the
   head tilted back.


3. Pinch closed the nostrils and open the MOUTH.
   Place the resuscitation shield and breathe into
   the shield (or the person’s mouth) until the
   person’s chest rises.


4. Place the palm of one hand on the back of the
   other hand and interlace the fingers.


5. Place the hands in the center of the person’s
   chest. (For an infant under 12 months, use the
   flat of the fingers on the center of the chest
   between the nipples.)


6. Sharply push downward to compress the chest
   about 2 inches. Pump the person’s chest in this
   way at the rate of 100 compressions per
   minute.


7. Give 2 normal breaths every 30 compressions.

When an AUTOMATED EXTERNAL DEFIBRILLATOR

(AED) is available, a second responder may add

DEFIBRILLATIONto the resuscitation efforts, which is

the next step. The AED unit determines whether

defibrillation is appropriate.

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