High altitude cerebral edema

Background

• Also known as HACE
• Progressive neurologic deterioration in someone with AMS or HAPE (due to incr ICP)
• Almost never occurs at <8000ft

Clinical Features

1. Altered mental status, ataxia, gait disturbance, stupor (most sensitive findings)
   1. Progresses to coma if untreated
2. Headache, nausea, and vomiting are not always present
3. Focal neuro deficits may be seen (3rd/6th CN palsies)
4. Seizures are rare

Differential Diagnosis

High Altitude Illnesses

• Acute mountain sickness
• Chronic mountain sickness
• High altitude cerebral edema
• High altitude pulmonary edema
• High altitude peripheral edema
• High altitude retinopathy
• High altitude pharyngitis and bronchitis
• Ultraviolet keratitis
• Dehydration
• Exhaustion
• Hypoglycemia
• Hypothermia
• Hyponatremia

Treatment

1. Immediate descent is the treatment of choice
2. If descent not possible use combination of:
   1. Supplemental O2 (goal SpO2 90%)
   2. Dexamethasone 8mg initially, then 4mg q6hr
   3. Acetazolamide 250 mg BID (better as ppx)
   4. Hyperbaric bag if available

Prevention

• Acetazolamide 125mg BID (250mg BID if greater than 100kg)
• Dexamethasone 2mg q6h OR 4mg q6h

See Also

High Altitude Medicine

Source

• Tintinalli
• Cone David, et al. Emergency Medical Services: Clinical Practice and Systems Oversight, 2 Volume Set. John Wiley & Sons, Dec 30, 2014.