Fainting
by Alton Thygerson

Last Saturday, a physician-lecturer used a participant to describe what was involved in a shoulder dislocation. Midway through his presentation, the participant suddenly collapsed into the arms of the physician.

Last month in one of my first aid/emergency care classes, while I was showing slides of wounds, a student collapsed.

Years ago, as a young boy my father came home telling about one of his employees who collapsed during a company first aid class.

A handy reference known as The Merck Manual, the best single guide for physicians, indicates that a sudden brief loss of consciousness not associated with a head injury is known as syncope or simple fainting. That is what happened in the three episodes described above. Specifically, The Merck Manual says they are cases of "vasovagal syncope." This type of syncope is usually precipitated by unpleasant emotional stimuli (i.e., sight of blood, strong fear), usually occurs in the upright position, and is often preceded by warning symptoms such as:

• nausea
• weakness
• yawning
• pale skin
• visual blurring
• sweating.

Simple fainting, sometimes called psychogenic shock, is a common and benign form of acute vascular shock that can actually have either physical or emotional causes (as in the cases above).

Most fainting episodes are associated with decreased blood flow (oxygen and/or glucose) to the brain. This may be caused by low blood sugar (hypoglycemia), slow heart rate ("vagal" reaction, in which the vagus nerve, which slows the heart rate, is over-stimulated from fright, anxiety, drugs, or fatigue), heart rhythm disturbances, dehydration, heat exhaustion, anemia, bleeding, and others.

Sitting or standing for a long time without moving, especially in a hot environment, can cause blood to pool in dilated vessels. This results in a loss of effective circulating blood volume, which causes the blood pressure to drop. As the brain's blood flow decreases, the person loses consciousness and collapses.

If you witness a fainting episode, or are with someone who is becoming lightheaded (i.e., sweating, weak, ashen colored), quickly help the person to lie down, with the legs elevated 8 to 12 inches. This position increases venous blood flow back to the heart, which in turn pumps more blood to the brain. Fresh air and a cold, wet cloth or towel for the face usually aids recovery.

After a fainting episode, examine the patient for any signs of serious injury. If nothing is suspected, have him or her sit for a while, drink cool, sweetened liquids, and slowly regain an upright posture.

Most fainting episodes are not serious and the victim regains consciousness quickly. However, seek medical attention if the victim:

• Is over 40 years old
• Has had repeated attacks of unconsciousness
• Does not waken within four or five minutes
• Loses consciousness while sitting or lying down
• Faints for no apparent Reason.

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