LESSON 2
HEART ATTACK AND CARDIOPULMONARY RESUSCIATION
2-1.
DEFINITIONS
a. Heart Attack. A heart attack (myocardial infarction) is the death of heart
muscle tissue caused by a blood clot (thrombus) or other substance circulating in the
blood (embolus) that blocks one or more of the coronary arteries (arteries that provide
the heart muscles with oxygen-rich blood).
b. Cardiac Arrest. Cardiac arrest (sudden death) is the sudden and
unexpected cessation of pulse and blood circulation. That is, the casualty's heart stops
beating. When the heart stops beating, the casualty's breathing will also stop and he
will loose consciousness, usually within 10 to 30 seconds of the cardiac arrest.
c. Clinical Death. Clinical death occurs as soon as the casualty's heart stops
beating, he stops breathing, and he looses consciousness. Clinical death can be
reversed by cardiopulmonary resuscitation (CPR).
d. Biological Death. Biological death usually occurs 6 to 10 minutes after
clinical death if efforts to restore breathing and heartbeat are not performed. Biological
death involves irreversible brain damage.
e. Cardiopulmonary Resuscitation. The prefix "cardio-" refers to heart,
"pulmonary" refers to the lung, and "resuscitation" means to bring a person who
appears to be dead back to consciousness. Thus, cardiopulmonary resuscitation
means to restore lung function (breathing) and heart function (blood circulation) to a
person who is clinically dead.
2-2.
CAUSES OF CARDIAC ARREST
The primary cause of sudden death (cardiac arrest) is myocardial infarction
(heart attack). Other causes of cardiac arrest include:
a. Drowning.
b. Electrical shock.
c. Poisoning
d. Suffocation.
e. Smoke inhalation.
MD0532
2-2