Indices for the role played by regional flow resistance in blood pressure reflex
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An index, α = (Δr/r)/(ΔR/R), is proposed for assessment of the relative degree of participation of a regional flow resistance in a blood pressure reflex, wherer andR are regional and total peripheral resistances respectively and Δ's refer to their reflexive changes. For actual computation, α =I (iΔP − PΔi)/i(IΔP − PΔI), whereI=cardiac output,i=regional flow rate,P=mean arterial pressure. When the change in cardiac output is neglegible, the above equation is simplified as Δ=1 − PΔi/iΔP. Another index,β = Δg/ΔG = (PΔi − iΔP)/(PΔI − IΔP), is introduced for the degree of contribution of a region to a reflex, whereg andG are regional and total conductances.αi = β1. Some examples of application of the indices are presented.
Key-WordsRegional Flow Cardiac Output Blood Pressure Reflex Flow Resistance Cardiovascular Regulation
SchlüsselwörterLokale Durchblutung Herzminutenvolumen Blutdruckreflex Stromresistenz Kreislaufregulation
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