AUTORADIOGRAPHIC DETERMINATION OF REGIONAL CEREBRAL BLOOD-FLOW AND METABOLISM IN CONSCIOUS RATS AFTER FLUID RESUSCITATION FROM HEMORRHAGE WITH A HEMOGLOBIN-BASED OXYGEN CARRIER

The effects of resuscitation fluids on the brain have been investigate d in previous studies by global measurements of cerebral blood flow an d metabolism. In this study we have examined the effects of a novel ha emoglobin-based oxygen carrier on local cerebral blood flow (LCBF) and local cerebral glucose utilization (LCGU) after resuscitation from a volume-controlled haemorrhage of 30 min (3.0 ml/100 g body weight) wit h ultrapurified, polymerized, bovine haemoglobin (UPBHB). LCBF and LCG U were measured in 34 brain structures of conscious rats 2h after resu scitation using quantitative iodo(C-14)antipyrine and 2-(C-14)-deoxy-D -glucose methods. The data were compared with a control group without haemorrhage and fluid resuscitation. In the haemorrhage group, LCBF in creased after resuscitation by 12-56% in the different brain structure s (mean 36%). LCGU changed less (0 to 18%, mean +9%). In the control g roup there was a close relationship between LCGU and LCBF (r = 0.95). After fluid resuscitation the relationship was preserved (r = 0.95), a lthough it was reset at a higher ratio of LCBF to LCGU (P < 0.05). We conclude that fluid resuscitation of a 30 min volume-controlled haemor rhage using the haemoglobin-based oxygen carrier, UPBHB, induced a mod erate degree of heterogeneity in the resulting changes of LCGU and LCB F. Local disturbances of cerebral blood flow or metabolism were not ob served.