Gravity-induced hyperventilation is caused by a reduced brain perfusion.

R Arieli; L E Farhi

doi:10.1016/0034-5687(87)90030-2

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Gravity-induced hyperventilation is caused by a reduced brain perfusion.

R Arieli·L E Farhi

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Abstract

The suggestion that hyperventilation caused by increased gravity is mediated by a decrease in brain perfusion has led us to propose a mathematical model based on: (1) the CO2 balance equation for the respiratory center (RC), and (2) the relationship between RC blood flow (QRC), foot-to-head acceleration (Gz) and PRCCO2, namely, QRC = [1 - a(Gz - 1)](b X PRCCO2 + c), where the coefficients a, b and c can be calculated from data in the literature. QRC is significantly affected by + GZ only at high PaCO2. The model can be used to calculate oxygen pressure in the RC; the numbers so obtained are in good agreement with measurements of jugular vein PO2 obtained by others.

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Blood Flow Velocity Brain Carbon Dioxide Gravitation Humans Hyperventilation Male Mathematics Models, Biological Respiration Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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R Arieli, L E Farhi. 1987. Gravity-induced hyperventilation is caused by a reduced brain perfusion.. https://doi.org/10.1016/0034-5687(87)90030-2

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