Intraoperative Monitoring of Local Hb-Oxygenation in Human Brain Cortex

Abstract

Neurosurgical interventions are frequently performed under conditions of hyperventilation in order to lower intracranial pressure. This treatment is accompanied by a decrease in cerebral blood flow (CBF) and thus a decrease in the oxygen supply rate. Lowering the PaCO2 (arterial PCO2) from 40 to 30 mm Hg induces a decrease in CBF of 40% (Thoresen et al. 1979). This, in turn, may cause disturbances in local oxygen supply. Because the brain is highly vulnerable to damage from even a brief imbalance of oxygen delivery and demand (O’Sullivan and Cunningham 1989), intraoperative disturbances of local oxygen supply must be avoided. Furthermore, it was shown that anaesthesia can cause a decrease in CBF and in cerebral oxygen uptake rate. Thus it is of interest to know the local oxygen supply to the brain under conditions of anaesthesia and hyperventilation.KeywordsCerebral Blood FlowBrain Blood VesselOxygen Supply RateIntegrate GradientTotal Cerebral Blood FlowThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.