Coriolis-induced cutaneous blood flow increase in the forearm and calf

Using venous occlusion plethysmography, Sunahara et al. reported that Corio lis-induced nausea was accompanied by an increase in forearm blood flow, su ggesting a decrease in sympathetic activity to this vascular bed. No signif icant blood pressure and heart rate changes were observed. Vasodilation of the limbs theoretically impairs orthostatic tolerance, particularly if bloo d flow is shown to increase simultaneously in the lower limbs. This study e xamined the latter possibility. Seventeen subjects were exposed to the Cori olis cross-coupling effects induced by 20 RPM yaw rotation, and a simultane ous 45 degrees pitch forward head movement in the sagittal plane every 12 s . Forearm and calf skin blood flow were monitored in real-time using laser Doppler flowmetry (PeriFlux 4001). Our results indicated a significant (p < 0.001) simultaneous forearm and calf skin blood flow increase as a result of Coriolis cross-coupling across all 15 susceptible subjects, No significa nt changes in blood pressure and heart rate were observed. Coriolis-induced cardiovascular changes may confound previous reports on reduced G toleranc e using groundbased centrifuges that invariably evoke cross-coupling effect s. (C) 2001 Elsevier Science Inc.