Salmeterol inhalation — prophylaxis studies showed partial benefit but not recommended
Patient Discharge Instructions
copy discharge instructions
What is High Altitude Pulmonary Edema
Fluid buildup in the lungs caused by rapid ascent to high altitude
Occurs in healthy people without warning
Not caused by heart disease
Typically develops within 2-4 days of arriving at a new altitude
Most often during the second night at a new altitude
Symptoms often worsen during sleep
Medications prescribed
Nifedipine — if prescribed
Take as directed: 30 mg extended-release tablet twice daily
May cause low blood pressure — rise slowly from sitting
Do not stop without medical advice
Carry supply for future ascents as prophylaxis
Supplemental oxygen — if prescribed
Use as directed to maintain oxygen levels
Do not adjust flow without medical advice
Activity and altitude restrictions
No reascent until completely symptom-free
SpO2 stable at rest and with gentle activity without oxygen or medications
Typically at least 1-2 days of full recovery required
Gradual reascent if resuming altitude activities
No more than 300-500 m sleeping altitude per day above 3,000 m
Rest day every 3-4 days
Avoid alcohol and sedating medications at altitude
Worsen breathing during sleep
Can mask early symptoms
Return to emergency department immediately for
Worsening shortness of breath or difficulty breathing at rest
Any return of pink or bloody sputum
Oxygen levels dropping or failure to maintain >90% on oxygen
Confusion, difficulty walking straight, or altered mental status
May indicate concurrent brain swelling from altitude
Persistent symptoms not improving after descent
Future altitude travel advice
High risk of recurrence — up to 60% chance on rapid reascent
Carry nifedipine on future altitude trips
Consider prophylactic nifedipine starting day before ascent
Inform future travel companions of HAPE history
Ensure they know how to respond to early symptoms
Consider cardiology evaluation
Testing for patent foramen ovale if recurrent episodes
Echocardiogram to assess pulmonary artery pressures
References
Guidelines and key sources
Bartsch P, Swenson ER. Acute High-Altitude Illnesses. New England Journal of Medicine. 2013
Comprehensive review of HAPE pathophysiology, clinical features, and management
Primary source for incidence, mortality, and clinical features used in this document
Hackett PH, Roach RC. High-Altitude Illness. New England Journal of Medicine. 2001
Classic clinical overview including diagnosis, treatment hierarchy
Basis for oxygen and nifedipine treatment protocols
Luks AM, Beidleman BA, Freer L, et al. Wilderness Medical Society Clinical Practice Guidelines for the Prevention, Diagnosis, and Treatment of Acute Altitude Illness: 2024 Update. Wilderness and Environmental Medicine. 2024
Current authoritative clinical guidelines from WMS
Luks AM, Auerbach PS, Freer L, et al. Wilderness Medical Society Clinical Practice Guidelines: 2019 Update. Wilderness and Environmental Medicine. 2019
Previous iteration of WMS guidelines
PDE-5 inhibitor prophylaxis recommendations
Swenson ER. Early Hours in the Development of HAPE: Time Course and Mechanisms. Journal of Applied Physiology. 2020
Pathophysiologic cascade and SpO2 diagnostic thresholds
Alarm features and field diagnostic criteria
Berger MM, Sareban M, Schiefer LM, et al. Effects of Acetazolamide on Pulmonary Artery Pressure After Rapid Active Ascent to 4,559 m. Journal of Applied Physiology. 2022
RCT evidence that acetazolamide does not reduce pulmonary artery pressure
Basis for acetazolamide not recommended for HAPE
Diagnostic and imaging references
Rabold M. High-Altitude Pulmonary Edema: A Collective Review. American Journal of Emergency Medicine. 1989
CXR findings in HAPE including right-sided predominance
Radiographic features distinguishing HAPE from cardiogenic edema
Gluecker T, Capasso P, Schnyder P, et al. Clinical and Radiologic Features of Pulmonary Edema. Radiographics. 1999
Radiographic comparison of cardiogenic vs noncardiogenic pulmonary edema
Reference for CT and CXR interpretation
Peter H. Hackett and David R. Shlim. High-Altitude Travel and Altitude Illness. CDC Yellow Book. 2025
Practical travel medicine perspective
Field management and discharge instructions basis
SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.