Hemolysis and hematology profile during perfusion: inter-species comparison

Introduction: Cardiopulmonary bypass components need to be tested on an ani mal model before their clinical application. Because their weight is simila r to that of man, the calf and pig are often used. This study compares the impact of prolonged perfusion on hemolysis and hematology profile in both s pecies. Methods: Three calves (mean bodyweight: 77.2+/-4.4 kg) and three pigs (80+/ -5.3 kg) were connected to an extracorporeal circulation circuit by jugular venous and carotid arterial cannulation, with a mean flow rate of 3.5L/min for 6h. After 7 days, the animals were sacrificed. A standard battery of b lood samples was taken before, throughout, and 24h, 48h and 7 days after by pass. ANOVA was used for repeated measurements. Results: Absolute values of red cell count were higher in the calf (p<0.001 ), while normalized values were higher in the pig (p<0.001). Absolute;value s of white cell count were higher in the pig, while normalized values diver ged toward the end of the perfusion with an increase in the calf and a decr ease in the pig (p<0.001). Free plasma Hb and LDH exhibited similar profile s in both groups. Conclusions: In the setting of prolonged perfusion, species type - bovine o r porcine - has an impact on hematology profile, but not on hemolytic param eters. These findings should be taken into account when cardiopulmonary byp ass components are tested.