The effect of a short-term passive orthostatic test on central blood flow in healthy adults
Year: 2024
Type: article
Abstract: When transitioning from a horizontal to a vertical position, the cardiovascular system experiences gravitational stress — blood is redistributed to the veins of the lower extremities, resulting in hypovolemia and a decrease in central venous pressure. In this study, the effect of short-term passive orthostatic test on central blood flow was investigated in healthy adults. Participants, secured with two seat belts, were placed on a specialized turntable with a footrest for five minutes in a supine position (Background-1). The table was then tilted to 75° for five minutes to simulate the standing position (Orthostasis), followed by a return to the supine position (After Orthostasis) for additional five minutes until all measurements returned to baseline (Background-2). During each phase, the electrocardiogram (ECG) (Lead I), rheogram (electrodes placed over the eyebrows and mastoid processes), and blood pressure were recorded. Data were analyzed using a comprehensive methodological and software toolkit: ‘Analysis of signals through polygraphic channels combined with EEG signals of Encephalan-SA’, Excel 16, and StatPlus 7.3.0. Statistically significant differences were observed between horizontal and vertical positions, with decreases in base impedance (BI), arterial vessel elasticity index (AVEI), time of slow blood filling (TSBF), rheographic index (RI), and systolic blood pressure (SYS). Conversely, the modulus of elasticity (ES), time of rapid blood filling (TRBF), dicrotic and diastolic index (DDI), and diastolic blood pressure (DAI) significantly increased.
Source: Integrative Physiology
Authors: Maria A. Gerasimova, Vera A. Semiletova, Evgeny V. Dorokhov
Language: English
Subfield: Cardiology and Cardiovascular Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W4409625151