title: [Characteristics of negative pressure inspiration effect on the cardiorespiratory system of humans in the conditions of 5-day dry immersion].
abstract: Changes in external respiration and central hemodynamics induced by negative (relative to atmospheric) inspiration pressure were studied in supine subjects before and on day-4 of a dry immersion (DI) experiment. Changes in the cardiorespiratory system as a result of negative inspiration pressure included rise of the amplitude of breathing motions and reduction of their frequency, and distinct breathing-related HR fluctuations. Combination of immersion and altered pressure in the mask caused breathing-related variations of systolic pressure and plethysmogram signal, and improved arterial blood oxygenation. These results can be useful for developing pressure-gradient methods of counteracting the adverse effects of blood redistribution toward the cranial-end.
authors.forename: Iu S
authors.initials: IuS
authors.lastname: Semenov
authors.forename: Iu A
authors.initials: IuA
authors.lastname: Popova
authors.forename: A I
authors.initials: AI
authors.lastname: D'iachenko
authors.forename: G D
authors.initials: GD
authors.lastname: Reushkina
authors.forename: V I
authors.initials: VI
authors.lastname: Kolesnikov
authors.forename: A V
authors.initials: AV
authors.lastname: Suvorov
mesh_terms: D000328:Adult; D000337:Aerospace Medicine; D001274:Atmospheric Pressure; D001794:Blood Pressure / Q000502:physiology; D006339:Heart Rate / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D007101:Immersion; D008297:Male; D012119:Respiration; D013026:Space Flight; D014893:Weightlessness / Q000009:adverse effects; D014894:Weights and Measures