Study of Treating HAPE with HBO in Situ at the Altitude of 4636 m

Study Objective ： To evaluate the treatment effect of HAPE with HBO in situ at an extreme altitude of 4636 m. To investigate the relationship between pulmonary hypertension （PH） and HAPE. To emphasize the importance of the treatment in situ. Methods： The 32 patients from the plateau of 4636 - 5130 m （the barometric pressure： 57.41 - 53.28 kPa/431.6 - 400.6 mmHg（1 mmHg = 133.3224 Pa）, the partial pressure of oxygen： 12.0 - 11.6 kPa/90.0 - 87.0 mmHg） were treated in situ of 4636 m altitude with HBO. Before and after the treatment, the clinical symptoms / signs, radiographic evidence, SaO2, and MPAP were compared. Results： The clinical symptoms/signs, and all the targets of the patients were improved dramatically （p 〈 0.001）. Conclusions： Treating HAPE with HBO is the most effective method among various therapies in situ at an extreme altitude. The pulmonary -artery pressure was significantly decreased. All eases showed improved immediately. Among the subjects, 11 eases （34.3 %） were cured at once. The therapy made it possible for patients to get further treatment at a lower altitude area with prospective good results. We suggested that treating HAPE with HBO should be the first choice in situ. There must be PH in the patients of HAPE, but the reverse is not the true. The PH is a mechanism of normal compensation of the body exposing in the hypoxie environment. It is very necessary for us to explore the threshold of PH when a HAPE happens.