Restoration of Oxygen Uptake and Blood Flow in the Rat Cerebral Cortex after Halothane Anaesthesia

Halothane decreases both the cerebral blood flow (CBF) and the cerebral metabolic rate for oxygen (CMRO2) when given in anaesthetic doses. A recent report (GJEDDE & HINDFELT 1975) suggests that when halothane is administered to rats for 1 hour, CBF and CMRO2 are depressed by about 30 and 40%, respectively, for as long as 4 hours after discontinuation of the halothane anaesthesia. In the present study rats were anaesthetized with 1% halothane for 1 hour, and CBF and CMRO2 were measured at the end of a 30 min recovery period, during which 70% N2O was administered. Comparison with animals maintained on 70% N2O throughout the entire 90 min period showed that previous halothane anaesthesia had no effects on CBF or CMRO2.