High-altitude cerebral edema
High altitude cerebral edema (or HACE) is a severe (frequently fatal) form of altitude sickness.[1] HACE is the result of swelling of brain tissue from fluid leakage and almost always begins as acute mountain sickness (AMS)[2]. Symptoms therefore usually include those of AMS (nausea/vomiting, insomnia, weakness, and/or dizziness) plus headache, loss of coordination (ataxia), and decreasing levels of consciousness including disorientation, loss of memory, hallucinations, irrational behavior, and coma.[1][2][3] In the presence of language barriers, HACE can be assessed by asking (or gesturing) for the climber to walk along a straight line.
HACE is considered to be preventable since it almost always occurs after ascending with the presence of AMS symptoms (one exception is when climbers become stranded for long periods of time at very high altitude, which is usually above 8,000 meters, especially without bottled oxygen)[2]. Nevertheless, the dangers of HACE are compounded by the tendency of its victims to deny having any problems at all[2]. Often they do not receive treatment until they have collapsed or their symptoms cause others to intervene. Severe instances quickly lead to coma and then death if not treated immediately. Oxygen administration and medications (dexamethasone) may temporarily alleviate symptoms and facilitate descent, which is the necessary life-saving measure. Hyperbaric bags are highly effective in conjunction with dexamethasone and, considering the cost and size of most commercial climbing expeditions, are also relatively cheap and lightweight (15 lbs). Evacuated patients should go to a medical facility for proper follow-up treatment.
Symptoms
Common symptoms of HACE appear in order as followed:[4]
- Confusion
- Changes in behaviour
- Fatigue
- Ataxia
- Difficulty speaking
- Vomiting
- Hallucinations
- Blindness
- Paralysis of a limb
- Seizure
- Unconsciousness
- Total paralysis
- Coma
| High-altitude cerebral edema |
|---|
See also
References
- ^ a b Roach, Robert; Stepanek, Jan; and Hackett, Peter. (2002). "24". Acute Mountain Sickness and High-Altitude Cerebral Edema. In: Medical Aspects of Harsh Environments. Vol. 2. Washington, DC. Retrieved 2009-01-05.
{{cite book}}: More than one of|location=and|place=specified (help)CS1 maint: location missing publisher (link) CS1 maint: multiple names: authors list (link) - ^ a b c d Dietz,Thomas E. (2000). Altitude Illness Clinical Guide For Physicians. Retrieved 2009-05-18.
- ^ AAR Thompson. "Altitude sickness". Apex (Altitude Physiology Expeditions). Retrieved 2007-03-06.
- ^ "High Altitude Cerebral Edema". The Guides Network. Retrieved 2010-02-09.