Massive exchange transfusions with crystalline hemoglobin solution and subsequent replacement of hemoglobin and blood volume.

Crystalline hemoglobin solution was used to exchange transfuse rats to 75 per cent blood replacement. At three hour intervals after transfusion, the rats received bolus injections of hemoglobin solution to replace plasma hemoglobin and intravascular volume lost during each time interval. At 12 and 24 hours after termination of exchange transfusion, the livers of five of six rats exhibited normal hepatic structure. One rat had centrilobular hepatic neurosis similar to that reported for rats given a single transfusion. Plasma hemoglobin, packed cell volume, plasma oncotic pressure and oxygen-carrying capacity of the intravascular fluid were monitored; the data demonstrate that changes observed in these parameters are rectified by the bolus injection which brought their values to the levels observed after transfusion. No hepatic lesions or other abnormalities were observed in the rats in the control group exchange transfused isovolemically with pooled rat blood or subjected to surgical procedures only. Serial bolus injections of hemoglobin solution, by rapidly restoring blood volume and hemoglobin concentration, appear to prevent the hepatic necrosis observed in rats a few hours after a single transfusion, as reported in previous studies.