A study of autonomic cardiovascular regulation in subjects with acute mountain sickness

Received: December 25, 2016; Accepted: January 15, 2017 ABSTRACT Background: Increased sympathetic activity is a part of the integrated physiological response to a hypoxic stimulus but it is not clear if it plays a role in the genesis of acute mountain sickness (AMS). Aims and Objectives: This study was conducted to evaluate the role of the autonomic nervous system in AMS during the initial phase of acute high-altitude exposure. Results: At high-altitude, the diastolic blood pressure (DBP) rise in response to sustained handgrip was higher in AMS subjects than the control group. High Altitude; Autonomic Nervous System; Acute Mountain Sickness INTRODUCTION A large number of people travel to high-altitude region all over the world for various reasons such as pilgrimage, trekking, mining or defense service requirements. The individuals who fail to adapt to these adversities may develop acute mountain sickness (AMS) or high altitude pulmonary edema (HAPE) or high altitude cerebral edema (HACE). [...]this study was conducted to elucidate the role of the ANS in AMS during the initial phase at acute high-altitude exposure. After recording baseline heart rate (HR) and blood pressure (BP), all subjects underwent four simple noninvasive cardiovascular reflex tests, namely, (a) HR response to deep breathing, (b) valsalva manoeuvre, (c) BP response to sustained handgrip, and (d) cold pressor test (CPT). RESULTS All 42 subjects successfully completed autonomic function tests at high altitude following 5th day of ascent to an altitude of 3500 m above sea level. 20 subjects had AMS, as indicated by a Lake...