Effect of modified ultrafiltration on bivalirudin elimination and postoperative blood loss after on-pump coronary artery bypass grafting: assessment of different filtration strategies.

OBJECTIVE: Bivalirudin has a short elimination half-life of approximately 25 to 30 minutes, but no antidote is available. We assessed the effect of four different strategies of modified ultrafiltration after cardiopulmonary bypass on the bivalirudin elimination and postoperative blood loss. METHODS: Five groups of seven patients undergoing elective "on-pump" coronary artery bypass grafting were enrolled in this controlled randomized investigation. The filtration strategies varied with regard to the filtration flow, the filtrate volume, the addition of vacuum suction to the filter system, and the performance of hemodiafiltration. Filtration was started after weaning from cardiopulmonary bypass (CPB). The cumulative postoperative blood drainage at 12 hours was recorded. RESULTS: Bivalirudin half-life in the control group was 0.6 +/- 0.11 hours, and the blood loss was 958 +/- 472 mL. Hemofiltration with a constant flow of 300 mL/m(2) body surface area/min and a filtrate volume of 3000 mL reduced the elimination half-life significantly to 0.47 +/- 0.11 hours. Adding the process of dialysis to hemofiltration resulted in a half-life of 0.52 +/- 0.04 hours and reduced the 12-hour postoperative blood loss significantly, compared to the control group, to 444 +/- 220 mL. The other strategies failed to augment the bivalirudin elimination and postoperative drainage effectively. CONCLUSION: Zero-balanced modified hemodiafiltration without addition of vacuum suction is effective in improving the elimination of bivalirudin after CPB and reducing the postoperative blood loss. Zero-balanced hemodiafiltration should be considered for the augmented elimination of bivalirudin in complex surgical procedures with a high risk of bleeding complications. However, larger investigations are warranted to confirm these results.

Duke Scholars

Author Solomon Aronson Anesthesiology, Cardiothoracic