HYPERDYNAMIC THERAPY FOR FOCAL CEREBRAL-ISCHEMIA OF RATS - USE OF COLLOIDAL VOLUME EXPANSION AND DOBUTAMINE

The effects of hyperdynamic therapy with colloidal volume expansion an d pharmacological augmentation of cardiac function with dobutamine on local cerebral blood flow (CBF) and the size of ischemic injury were i nvestigated in rats subjected to 6 h of middle cerebral artery (MCA) o cclusion. At 45 min after MCA occlusion, each rat was randomly assigne d to one of the following treatment groups: (1) control; (2) hetastarc h infusion (HES); and (3) hetastarch plus dobutamine (12 mug/kg/min) i nfusion (HES/DOB). In both the HES and HES/DOB groups, cardiac output and local CBF in ischemic brain markedly increased after treatment and infarction volumes were significantly reduced as compared to the cont rol group. There were, however, no significant differences between bot h groups apart from a dobutamine-induced tachycardia. Colloidal volume expansion augmented cardiac output, increased CBF in ischemic brain, and substantially modified the extent of ischemic injury. However, the addition of dobutamine did not bring about adjunctive beneficial effe cts of cardiac performance, CBF, or the degree of ischemic brain damag e in the rat focal ischemic model.