Responses of central and cerebral hemodynamics to active orthostasis in healthy subjects

Abstract

Regular trends in changes in cerebral and central hemodynamics were studied in 28 healthy men aged 20–26 years during active orthostatic stress. The hemodynamic parameters of the blood flow in the middle cerebral artery (MCA), systemic hemodynamics, and parameters of pulmonary ventilation were recorded simultaneously for 10 min while a subject was in a horizontal position and for the same period after the position had been changed to vertical (active rising). In healthy subjects, several types of responses of cerebral and central hemodynamics were detected during active orthostasis.