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failure, death.
Using Advanced Tools: Pulse oximeter: Oxygen levels will be lower with HAPE or other altitude illnesses.
CXR: Fluffy infiltrates in mid-lung fields or spreading throughout lungs.
Assessment:
Diagnosis is made on basis of clinical presentation and exposure history.
Differential Diagnosis
AMS or HACE in addition to HAPE - see Acute Mountain Sickness and High Altitude Cerebral Edema
sections)
Pneumonia - fever greater than 101°F; infected (purulent) sputum; symptoms before traveling to high altitude
(see Respiratory: Pneumonia)
Pulmonary embolus - chest pain with breathing, blood clot in leg veins (pain and swelling) (see Respiratory:
Pulmonary Embolus)
High-altitude cough - chronic, dry cough can occur at very high altitude (usually greater than 15,000 ft) due to
irritation of throat by breathing cold, dry air. Not associated with rales, sputum production, or other signs
or symptoms of HAPE.
Asthma - history of asthma; breathing cold air or allergen exposure; wheezing (see Respiratory: Asthma)
Plan:
Treatment
Primary:
- Immediately evacuate to lower altitude (1000 to 2000 feet lower may be lifesaving) by litter (walking
will worsen HAPE.). - Oxygen : 6 liters/minute or greater by mask.
- Nifedipine: break 20 mg capsule and hold under tongue, then 20 mg sustained release tablet every six
hours swallowed. - If HACE also present, treat it (see High Altitude Cerebral Edema section).
- If comatose, endotrachael tube intubation to protect airway. (see Procedure: Intubation a Patient)
NOTE: Nifedipine is not on SOF drug list, but is available through military medical supply channels and
civilian sources.
Alternative: - If evacuation to lower altitude not possible, bed rest, high-flow oxygen by mask, nifedipine, and treatment
in portable hyperbaric (‘pressure’) chamber*. (see Procedure: Portable Pressure Chamber) - If nifedipine not available, use acetazolamide 250 mg (do not give if allergic to sulfa) po q 6-8 hours.
- End-positive-airway-pressure (EPAP) mask may be helpful, if available.
Primitive: Descent is the best treatment for all altitude illnesses (e.g., AMS, HACE, HAPE). ‘Pursed-lip’
breathing may help increase oxygenation. Patient in prone, slightly head-down position for brief period (10-20
min) may help drain lung fluid through the mouth temporarily (if patient can tolerate that position).
Patient Education
General: HAPE is caused by rapid ascent before the body has a chance to adjust to high altitude. More likely
to occur if exercise vigorously during first 3 to 5 days after ascent, or keep ascending while symptomatic.
Activity: Bed rest (physical activity makes HAPE worse).
Medications: Nifedipine can lower the blood pressure and cause dizziness when sitting up or standing
rapidly from a prone position. It can cause swelling (edema) of the hands, lower legs and feet.
Prevention and Hygiene: Ascend slowly (less than 1000 ft/day above 8000) with rest day (no ascent)
every 3-4 days. Do not continue ascent with symptoms of altitude illness or difficulty breathing. Sleep at as
low an altitude as possible (1000-2000 ft lower than working altitude) until body adjusts (7-10 days). Avoid
vigorous physical activity for first 3 to 5 days after ascent. If you have had HAPE during previous trips to high
mountains, you should take nifedipine when going to altitude in the future.
No Improvement/Deterioration: HAPE can be rapidly fatal if not treated. Seek medical attention for more
difficulty than companions breathing during exercise or at rest. Seek medical attention for a cough, or cough
up blood or pink, or frothy sputum. Seek medical attention if hear or feel ‘gurgling’ in chest when breathing.