EFFECTS OF ACETAZOLAMIDE ON OVERNIGHT OXYGENATION AND ACUTE MOUNTAIN-SICKNESS IN PATIENTS WITH ASTHMA

The aim of the study was to assess effects of acetazolamide in Prevent ion of acute mountain sickness (AMS) and on overnight oxygenation, in patients with asthma treated at the altitude of 3,200 m. Sixteen patie nts with asthma, 6 males and 10 females, mean age 32 yrs, were first i nvestigated at low altitude (760 m). They presented with mild airways obstruction, normal arterial blood gases, and normal oxygenation at ni ght studied by pulse oximetry. After initial investigations, patients were divided by random number into the treated (T) and control (C) gro ups of eight patients each. T group patients received acetazolamide, 7 50 mg dally for 2 days, before the ascent and on the first day at alti tude (3,200 m). Symptoms of AMS developed in seven patients from group C and in three from group T. The overnight pulse oximetry, performed on the first night at altitude, revealed that group T patients had sta tistically higher (p<0.05) initial, 91 vs 87%, mean, 90 vs 86%, and mi nimum, 84 vs 75%, arterial oxygen saturation than group C patients. Ov ernight pulse oximetry was repeated on the 5th, 10th and 17th day at a ltitude, and showed that in group C patients, from the 5th day onwards , oxygenation improved to the level observed in group T patients on th e first night We conclude that pretreatment with acetazolamide before the ascent prevented patients with asthma from developing symptoms of AMS, and alleviated acute changes in arterial oxygen saturation brough t about by the high altitude hypoxia.