-IBIS-1.5.0-
tx
nervous system
hypothermia
diagnoses

definition and etiology

definition:
Generalized lowering of the body temperature to less than 35° C
(95° F). Usually termed "accidental hypothermia". This is a medical emergency.

etiology:
This is seen particularly in the elderly and inebriated and especially in the sick elderly person. Factors that predispose to hypothermia are Addison's disease; hypoglycemia; myxedema; cirrhosis; pituitary insufficiency; starvation; brain injury; and any illness that immobilizes the patient. Hypothermia is usually seen during the winter months. Elderly patients may become hypothermic even in homes where the temperature is kept at 65° F, where previous cold exposure was at substantially lower temperatures.

signs and symptoms

signs and symptoms:
Onset is usually gradual over hours or days.
• Progress of mental status as the body temperature drops: Fatigue, weakness, incoordination, apathy, drowsiness, stupor and coma (below 90° F).
• Patient's body is cold to touch all over.
• No shivering.
• Patient's body is stiff.

lab findings:
• Acid-base disturbances: respiratory alkalosis then respiratory acidosis; metabolic acidosis.
• Hemoconcentration.
• Decreased WBCs with normal differentiation.
• DIC can occur during rewarming.
• Pancreatitis.
• Urine changes: glycosuria and natriuresis are possible; oliguria with complications.

course and prognosis

The mortality rate is approximately 50% in severe cases, and increases when there is a previous severe disease present. Common complications include pancreatitis, gangrene of the extremities, renal failure, metabolic acidosis, pneumonia, and pulmonary edema.

Treatment is reheating, usually rapidly.

see: frostbite

differential diagnosis

• frostbite
• cerebrovascular accidents
• intoxication
• medication overdose
• complication of endocrine condition (e.g. DM)


footnotes