CHANGES IN HUMAN CEREBRAL BLOOD FLOW CONSEQUENT ON ALTERATIONS IN BLOOD GASES

Abstract

By a thermoelectric blood flow recorder, observations were made of the change in blood flow through an internal jugular vein of unanesthetized human subjects, following changes in the CO2 and the O2 tension of the blood. Increase in the CO2 and decrease in the O2 tension of the arterial blood result in an increase in the cerebral blood flow, chiefly because of the dilatation of the cerebral vascular bed. Decrease in CO2 tension of the arterial blood results in a decrease in blood flow, chiefly because of a constriction of the cerebral vascular bed. The effects due to changes in CO2 tension are much more marked than those due to changes in Oa tension.