Relation between arterial blood pressure and cerebral blood flow velocity in simulated sleep apnea.

Obstructive Sleep Apnea (OSA) is one of the most common breathing disorder, affecting approximately 27% of U.S. adults. Limited data have suggested that OSA causes cerebral autoregulation impairment, thus being an important risk factor to stroke. The objective of this paper is to investigate and measure the relation between arterial blood pressure (BP) and cerebral blood flow velocity (CBFV) in simulated apnea. Sixteen healthy subjects (9 male, 7 female) of 29±4.89 yrs age and body mass index of 24.07±4.84 kg/m(2) participated in the study. Four protocols were used; sitting 30 seconds, 90 s, and supine 30 s and 90 s. Our results showed that systolic BP and peak CBFV were correlated with average r=0.672 +0.265. Also, CBFV exhibited a significantly higher percent rise than BP. Thus, our findings suggest that cerebral autoregulation may be impaired during apnea episodes.