shown that hypoxia results in reduced nitric oxide levels, a principle cause of pulmonary vasoconstriction and that inhalation of nitric oxide can reduce hypoxic pulmonary hypertension, improve the patient's ventilation to perfusion ratio, improve hypoxemia, and improve HAPE in patients with signs and symptoms, as well as decrease hospitalization time with few adverse effects. Accordingly, we suggest that nitric oxide inhalation should be considered in the treatment of HAPE. It should be administered via a nasal catheter at a dose of 10 ppm (0.001%) at a flow rate of 3-5 L/min for 30 min in normal air or in oxygen.