Critical Closing Pressure as the Arterial Downstream Pressure with the Heart Beating and during Circulatory Arrest

Abstract

Thus, during arrest, Pcrit can be closely predicted after > or = 7 s, regardless of the model; two-compartment and pressure-dependent conductivity models provide a better fit than a single-compartment model, and actual Pcrit is much less than Pcrit calculated with the heart beating. Irrespective of uncertainties in whether Pcrit calculated with the heart beating or during arrest is the "true" Pcrit prevailing physiologically, linear vascular resistance is markedly less when substituting Pcrit for central venous pressure as the downstream pressure.