[Use of dispersion analysis in the evaluation of the effects of immersion and individual differences on the variability of orthostatic reactions]

With the use of dispersion analysis the variation of indices of central and peripheral hemodynamics in healthy volunteers stayed from 1 to 7 days under conditions of "dry" immersion (DI) was studied. Nine persons were investigated at rest, 5 individuals during orthostatic tests before and after dry immersion sessions. The central hemodynamic indices were calculated, the arterial pressure (AD) was measured by Korotkoff's method, indices of rheoencephalographic and rheoplethysmographic indices of lower leg were found. The significant differences of mean values of measured parameters before and after DI at rest were not revealed. Two-factor dispersion analysis of the orthostatic test data revealed the high levels of significance of influencing immersion and personality factors as well as their interaction on the variation of most indices. For excluding an individual uniformity there has been done an analysis of dynamics of indices according to their relative values which allowed one to isolate qualitative peculiarities of changes and distinctions between persons with different orthostatic tolerance even before orthostatic testing.