Haemostatic profile of small children during and following cardiopulmonary bypass

Objective: We evaluated changes of the haemostatic system during pediatric cardiac surgery during and after cardiopulmonary bypass (CPB).Method: Twenty-five children under 15 kg of body weight under-going open-heart surgery were divided into three groups; 9 patients (Group A), no bank blood was used throughout the surgery; 8 patients (Group B), packed red cells were used in the priming of CPB circuit; 8 patients (Group C) in cyanotic condition, for whom surgery was performed without bank blood. CPB caused a significant decrease of platelet counts in all three groups, the levels of which remained similar next morning.Results: Platelet counts decreased more significantly in Group C (59±27 k/mm³) than in Group A (119±42 k/mm³) and B (104±27 k/mm³). Platelet function-platelet activating factor test (HemoSTATUS^TM) did not significantly decrease throughout the perioperative period in Group A. Hemo-STATUS^TM value decreased during CPB and recovered after CPB in Group B and C. Prothrombin time international ratio (PT-INR) and activated partial thromboplastin time were significantly prolonged just after CPB and recovered until next morning in all three groups. PT-INR was more prolonged in Group C (2.92±0.62) than in Group A (2.08±0.27) and B (2.42±0.42). There was no significant difference in postoperative bleeding for the first 12 hours among the three groups.Conclusion: Although extreme hemodilution during CPB significantly impairs the coagulation and platelet system, these changes are usually transient and tolerable with minimal postoperative hemorrhage. However, a prolonged CPB and preoperative cyanotic condition may induce a critical decrease of platelet counts and increase postoperative bleeding.