Remote ischemic preconditioning alleviates hemodynamic changes induced by acute altitude exposure

Objective To observe the effects of remote ischemic preconditioning (RIPC) on hemodynamic parameters and cerebral oxygen saturation in healthy adults under acute exposure to altitude. Methods Twenty-four healthy male cadets (24.0±1.7 years old) were recruited from Army Medical University during March and July, 2020, and equally and randomly divided into control and RIPC groups. After the hemodynamic parameters and cerebral oxygen saturation were measured at baseline for all participants, those of the RIPC group were subjected to 7 consecutive days of upper limb ischemic preconditioning with a pneumatic sphygmomanometer, while those of the control group underwent the same procedure but without ischemic treatment. A hypobaric chamber was used to simulate the oxygen partial pressure and atmospheric pressure at an altitude of 4 000 m. The changes of mentioned indexes were observed and compared between the 2 groups, before decompression and 2 h after reaching the simulated altitude. Moreover, blood samples of the