Estimating Total Cerebral Blood Flow From the Initial Slope of Hydrogen Washout Curves • An initial slope index of total cerebral blood flow, measured by the hydrogen clearance technique, shows a high correlation with flows calculated by bicompartmental analysis. In 247 flow measurements done on 41 rhesus monkeys, a linear regression analysis between these two methods of calculating flow shows ...

To determine whether dynamic cerebral autoregulation is impaired during orthostatic stress, cerebral blood flow (CBF) velocity in the middle cerebral artery (transcranial Doppler) and mean arterial pressure (MAP; Finapres) were measured continuously in 12 healthy subjects during ramped maximal lower body negative pressure (LBNP) to presyncope. Velocity and pressure were averaged over 6-min peri...

BACKGROUND Hypotensive neonates who have been treated with dopamine have poorer neurodevelopmental outcome than those who have not been treated with dopamine. We speculate that dopamine stimulates adrenoceptors on cerebral arteries causing cerebral vasoconstriction. This vasoconstriction might lead to a rightward shift of the cerebral autoregulatory curve; consequently, infants treated with dop...

OBJECTIVE The aims of this study were to document the incidence of impaired cerebral autoregulation in children with traumatic brain injury using transcranial Doppler ultrasonography and to examine the relationship between autoregulatory capacity and outcome in children following traumatic brain injury. DESIGN Prospective cohort study. SETTING Harborview Medical Center (level I pediatric tr...

Validation of Jugular Venous Flow as an Index of Total Cerebral Blood Flow • Values of total cerebral blood flow in man measured by the indicator dilution method are compared with values of total internal jugular venous flow measured by the thermal dilution method. Except in the case of an extremely labile cerebral hemodynamic state, the results agree within the accuracy of the two methods, sug...