[Effects of several methods of general anesthesia on the cerebral blood flow and cerebrovascular reactivity: transcranial dopplerography data].

Effects of some methods of total anesthesia on the cerebral bloodflow and cerebrovascular reactivity was studied by transcranial dopplerography. Ketamine appreciably increases the cerebral bloodflow if no benzodiazepines are injected simultaneously. In patients with intracranial abnormalities ketamine can increase intracranial hypertension and disorder the cerebral perfusion. Despite the manifest hypotensive effect of diprivan, the autoregulation reserve of the cerebral bloodflow is not changed, probably due to the indirect vasoconstrictive effect of the drug. Total anesthesia with N2O and fentanyl virtually does not influence brain circulation.