Acclimatization at high altitude in gradual and acute induction. Purkayastha, S. S., U. S. Ray, B. S. Arora, P. C. Chhabra, L. Thakur, P. Bandopadhyay, W. Selvamurthy. Defence Institute of Physiology, and Allied Sciences,Lucknow Road, Timarpur, Delhi-110054, India
APStracts 2:0166A, 1995.
The study assessed physiological responses to induction to high altitude(HA) first to 3,500m then to 4,200m and compared the time course of altitude acclimatization in two groups of male volunteers. Acutely inducted group (AI) was transported by aircraft to 3,500m in 1 h, while gradually inducted group by road(RI)in 4 days. Baseline recordings of basal cardiovascular, respiratory and blood gas variables were monitored at sea level as well as at 3,500mon day -1,3,5 and 7. Blood gases were measured on day-10 also. After 15 days at 3,500m they were inducted to 4,200m by road and measurements were repeated on day-1, 3 and 5, except blood gas variables, which were done on day-10 only. AMS symptoms were recorded throughout.The responses of RI were stable by day-3 of induction at 3,500m whereas it took 5 days for AI. Four days in transit for RI appears equivalent to 2 days at 3,500m for AI. Acclimatization schedule of 3 and 5 days respectively for RI and AI is essential to avoid malacclimatization/HA-illness. Both groups took 3 days at 4,200m to attain stability for achieving acclimatization.

Received 17 October 1994; accepted in final form 28 March 1995.
APS Manuscript Number A1064-4.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 25 April 1995.