Regional cerebral blood flow in the acute stage of experimentally induced subarachnoid hemorrhage

Abstract
Subarachnoid hemorrhage (SAH) was induced in 13 adult mongrel cats by a slow injection of fresh autogenous blood into the cisterna magna. Serial determinations of regional cerebral blood flow (rCBF) in the cortex and deep-seated areas (internal capsule, thalamus, and caudate nucleus) were made during the following 2 hours, while intracranial pressure (ICP) was maintained at normal values. A decrease in rCBF was observed in all the areas examined. This reduction followed a characteristic triphasic pattern with an initial steep decline immediately after the SAH. The clinical implications of these findings are discussed.