Effects of extremes of respiratory and metabolic alkalosis on cerebral blood flow in man.

Abstract

S. CRAIGHEAD ALEXANDER. Efects of extremes of respiratory and metabolic alkalosis on cerebral blood Jlow in.man. J. Appl. Physiol. 24(l): 60-65. 1968.-Cerebral blood flour has been meas-ured during steady states of both respiratory and metabolic alkalosis in lightly anesthetized man. When mechanical hyper-ventilation decreased arterial Pco2 (PacoY) from 37 to 19 torr, cerebral blood flo\\v \\yas louvered from 44.1 to 25.3 ml/100 g per min, a 43y0 diminution. Additional reduction of Pacdz to 10 torr louvered mean cerebral blood flo\\v an additional 17 % to 2 1.O ml/100 g per min. In two subjects minimum values of cerebral blood flow were achieved at Pado levels near 19 torr, but in four others only at greater degrees of hypocarbia. The mean value for maximum cerebral vascular resistance during hyperventilation and respiratory alkalosis kvas 3.5 torr/ml per 100 g per min. Metabolic alkalosis induced by sodium bicar-