(1)
The pain may spread to a shoulder, an arm, or neck.
(2) The duration of the pain is usually 2 minutes or longer. The pain may
come and go.
b. The person may also feel weak, have shortness of breath, perspire, and be
nauseous (feel like vomiting).
c. Signs and symptoms may come and go, depending upon factors such as the
severity of damage to the casualty's heart and the casualty's physical activity during or
immediately before the heart attack. The disappearance of symptoms may cause the
casualty to deny that he has suffered a heart attack.
d. In some cases, the heart attack results in cardiac arrest (no pulse or
heartbeat).
2-5.
As stated previously, the blood supplies the cells of the body with oxygen. In a
medical emergency, you must ensure that this supply of oxygen continues. The supply
of oxygen to the body cells is threatened whenever the person stops breathing on his
own or when the person's heart stops pumping blood. When the oxygen supply fails,
cells begin to die. The length of time required for a cell to die after the oxygen supply
has stopped depends upon several factors. One of the most important factors is the
type of cell involved. Brain cells are the most sensitive. Permanent brain damage
usually occurs if the oxygen supply is stopped for more than 6 minutes. Therefore, a
casualty who has suffered a cardiac arrest must have breathing and circulation restored
quickly if biological death is to be prevented. The process of restoring breathing is
called rescue breathing. Artificial heartbeats are produced by administering chest
compressions. In neither case, however, is the substitute measure as efficient as the
body's natural process.
2-6.
EFFECTS OF RESCUE BREATHING
Rescue breathing consists of two phases. In the first phase, the rescuer blows a
breath into the casualty's lung. This replaces the casualty's normal inhalation. Once
the inhalation phase is completed, the rescuer breaks his seal over the casualty's
airway. This allows the casualty's body to exhale on its own.
a. Inhalation Phase. Once the rescuer seals the casualty's airway so that air
cannot escape, he blows air into the casualty's airway (usually though the casualty's
mouth). The pressure from the rescuer's breath forces air through the rest of the
respiratory tract and causes the alveoli to expand. This causes in the lungs as a whole
to expand. When the lungs expand, they cause the rib cage (chest) to rise and the
diaphragm to flatten somewhat.
MD0532
2-5