Effects of head-down tilt and head-up tilt mode of repeated body position changes on human orthostatic tolerance
WANG Yingfeng
LIU Min
WU Ping
GONG Xianwen
ZHOU Yue
WU Bin
Abstract：Objective To explore the effects of the head-down and head-up tilt (HDT/HUT) mode of repeated body postural changes on human orthostatic tolerance. Methods Twelve subjects were exposed to an HDT/HUT mode of repeated body position change experiment. Before and after the experiment, the subjects were exposed to head-up tilt (HUT) to test their orthostatic tolerance. The heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), stroke volume (SV), cardiac output (CO), and total peripheral resistance (TPR) of the first minute in the HUT and supine position before and after the experiment were recorded for analysis. Results After the experiment, the HR, SV and CO in the supine position decreased significantly (P<0.05 or P<0.01), TPR increased significantly (P<0.01), DBP, MAP, SV and CO that were measured one minute into HUT decreased significantly (P<0.05 or P<0.01), but TPR increased (P<0.01). Conclusion The head-down tilt and head-up tilt mode of repeated body position changes can cause a decrease of human orthostatic tolerance.
Keywords：head-up tilthead-down tiltrepeated body position changeorthostatic tolerance
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：4( 299-301,305 )