EXPERIMENTAL TECHNIQUES FOR THE PREVENTION OF SLUDGING OF ERYTHROCYTES IN EXTRACORPOREAL CIRCULATION

SUMMARY By means of a radioisotope method which quantitates erythrocyte sequestration, the effects of ascorbic acid, low molecular weight dextran, and 5 per cent dextrose primer on erythrocyte sequestration in the microcirculation following extracorporeal circulation in dogs were evaluated. Prior to perfusion, 3.0 per cent of the total circulating red cell mass was sequestered, presumably as the result of pentobarbital anesthesia, whereas no sequestration was observed in unanesthetized dogs. Following the perfusion, 11.8 per cent of the total body erythrocytes was demonstrated to be sequestered and some erythrocytes remained sequestered in the microcirculation for as long as 60 to 90 minutes. When ascorbic acid was administered, only 4.6 per cent of the erythrocyte mass was sequestered. Low molecular weight dextran and 5 per cent dextrose primer diminished the sequestration to 3.2 per cent and 5.4 per cent, respectively. The beneficial effects of various perfusion techniques were also demonstrated by the microscopic study of the mesenteric microcirculation. On the basis of this study, ascorbic acid is being used as the anti-sludging agent in clinical perfusions.