mountain sickness(acute;chronic)

A small percentage of people who ascend rapidly to high altitudes become acutely sick and can die if not given oxygen or removed to a low altitude. The sickness begins from a few hours up to about 2 days after ascent.

.Two events frequently occur:

1. Acute cerebral edema.

 2. Acute pulmonary edema

Chronic Mountain Sickness:

Occasionally, a person who remains at high altitude too long develops chronic mountain sickness, in which the following effects occur:

(1) The red cell mass and hematocrit become exceptionally high,

(2) the pulmonary arterial pressure becomes elevated even more than the normal elevation that occurs during acclimatization,

(3) the right side of the heart becomes greatly enlarged,

(4) the peripheral arterial pressure begins to fall,

(5) congestive heart failure ensues, and

(6) death often follows unless the person is removed to a lower altitude.