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Clinical Summary

Retinal hemorrhages are common above 5200 m (17,060 ft) and are not always associated with acute mountain sickness (AMS). High-altitude retinal hemorrhages (HARH) are rarely symptomatic, but if found over the macula, these hemorrhages may cause temporary blindness. The diagnosis can be established by ophthalmoscopy. Without visualization of the lesion, the differential diagnosis of unilaterally decreased vision or blindness at high altitude includes migraine equivalent, cerebrovascular accident, and dry eye (often unilateral, due to strong winds), as well as all conditions found at sea level.

Emergency Department Treatment and Disposition

HARH generally resolve spontaneously after descent to lower altitudes. No treatment is necessary for asymptomatic HARH. Patients with HARH associated with a decrease in vision should be referred to an ophthalmologist for follow-up.

Figure 16.1.

High-Altitude Retinal Hemorrhage. Fundoscopic appearance of high-altitude retinal hemorrhage. (Photo contributor: Peter Hackett, MD.)


  1. Patients with blurred vision and unilateral mydriasis at the high altitude should be asked about use of medications, including transdermal scopolamine patches.

  2. As with almost all altitude-related problems, descent is the primary treatment. This is not emergent unless associated with severe altitude illness or progressive visual loss.

  3. Although most symptomatic HARH resolve completely in 2 to 8 weeks, cases of permanent paracentral scotomata have been reported.

The authors acknowledge the special contributions of Peter Hackett, MD, The Institute for Altitude Medicine Telluride, Colorado; Edward Otten, MD, University of Cincinnati, Cincinnati, Ohio; James O'Malley, MD, Providence Alaska Medical Center, Anchorage, Alaska; Murray Hamlett, DVM and Kathy McCue, MD, Alaska Native Medical Center, Anchorage, Alaska; Sheryl Olson, RN, Monitou Springs, CO; Luanne Freer, MD, Yellowstone National Park, The Nashville Zoo, Nashville, TN; and the Nova Scotia Museum of Natural History, Halifax, Nova Scotia, Canada. The authors thank Joseph C. Schmidt, MD, Lawrence B. Stack, MD, and Alan B. Storrow, MD for their contributions to prior editions.

Clinical Summary

High-altitude pulmonary edema (HAPE) is a form of noncardiogenic pulmonary edema, generally beginning within the first 2 to 4 days after ascent above 2500 m (8202 ft). The earliest symptoms are fatigue, weakness, dyspnea on exertion, and decreased exercise performance. Symptoms of acute mountain sickness (AMS) such as headache, anorexia, and lassitude may also be present, but HAPE may develop without AMS. If untreated, a persistent dry cough develops, followed by tachycardia and tachypnea at rest with cyanosis. Patients suffering from HAPE generally experience nocturnal onset, and frequently report progressively worsening symptoms at night. Eventually the victim develops dyspnea at rest and orthopnea with audible crackles in the chest. Pink frothy sputum is a grave sign. Patients may experience concurrent mental status changes and ataxia due to hypoxemia or associated high-altitude cerebral edema (HACE).

Emergency Department Treatment and Disposition


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