Estimation of critical closing pressure using intravascular blood pressure of the common carotid artery.

Purpose: Radial artery, femoral artery, and aortic arterial blood pressures (ABPs) can be used to estimate cerebral critical closing pressure (CrCP) and resistance-area product (RAP). However, the use of the common carotid artery (CCA) intravascular blood pressure to estimate CrCP is unclear. Thus, using continuous ABP monitoring, we compared the CrCP and RAP estimated from CCA measurements with the corresponding values acquired from the radial artery.

Methods: In this retrospective cross-sectional study, we analyzed CrCP and RAP estimations from 21 patients with normal cerebral blood vessels between July 23, 2010, and February 9, 2011, using linear regression of the cerebral blood flow velocity-ABP relationship.

Results: Bland-Altman analysis showed that the average differences (95% limits of agreement) between the radial artery and the left CCA were -6.3 (-53.1 - 40.6) mmHg and -0.08 (-0.41 - 0.25) mmHg s cm for CrCP and RAP, respectively.

Conclusions: The CrCP and RAP estimated from the CCA measurements are consistent with the corresponding values obtained from the radial artery.