COMPARISON OF THE EFFECTS OF RED-CELL SEPARATION AND ULTRAFILTRATION ON HEPARIN CONCENTRATION DURING PEDIATRIC CARDIAC-SURGERY

Objective: To determine the effects of red cell separation and ultrafi ltration on heparin concentration. Design: Prospective study. Setting: University-affiliated, pediatric medical center. Participants: Thirty -one children undergoing cardiac surgery. Interventions: Blood sampled for heparin concentration and coagulation tests. Measurements and Mai n Results: Thirteen infants underwent modified veno-venous ultrafiltra tion (UF) after cardiopulmonary bypass (CPB). In addition, residual bl ood in the CPB circuit was hemoconcentrated by UF and reinfused (UF gr oup). Heparin concentration increased from 2.0 +/- 0.6 to 2.5 +/- 0.8 U/mL, following modified UF; while activated coagulation time (ACT) de creased from 701 +/- 177 to 627 +/- 107 seconds. Heparin concentration of CPB circuit residual increased from 1.9 +/- 0.7 to 3.1 +/- 1.0 U/m L. In 18 children (older than 1 year old), the residual blood in the C PB circuit was hemoconcentrated by cell separation (CS) and reinfused (CS group). Heparin concentration of CPB circuit residual decreased fr om 2.6 +/- 0.6 to 0.3 +/- 0.2 U/mL. After reinfusion, patient heparin concentration remained unchanged at <0.05 U/mL. Thrombin time increase d from 28 +/- 6 to 48 +/- 29 seconds and did not correlate with H. Con clusions: The plasma concentration of heparin increased after veno-ven ous modified UF of the patient. Heparin concentration also increased a fter UF of residual CPB circuit blood. In contrast, circuit blood hemo concentrated by CS contained minimal heparin, and, when infused, did n ot increase patient's heparin concentration. ACT and thrombin time did not correlate with heparin concentration. Copyright (C) 1997 by W.B. Saunders Company.