Cardiac Surgery: In Vivo Titration of Protamine

Summary

Safe use of cardiopulmonary bypass (CPB) requires massive doses of intravenous unfractionated heparin. At end-CPB, residual heparin is neutralized with intravenous injection of protamine sulfate. This prospective, randomized, controlled study will be conducted in 82 voluntary subjects admitted for elective, first intention, cardiac surgery requiring cardiopulmonary bypass. Each will be randomly assigned to one of two groups. The control group will be submitted to a standard protamine infusion of 1.3mg :100U of the total heparin dose given during bypass. The test group will receive an infusion of protamine (over 15 minutes) until activated clotting time (ACT) values (determined every 3 minutes) depict a plateau, sign that the optimal protamine to heparin ratio has been attained. The investigators hypothesize this new in vivo titration method to be as efficient as the standard protocol (adequacy of heparin neutralization, % heparin rebound, bleeding, and transfusion), and potentially safer by its ability to prevent protamine overdose and its deleterious impact on platelet function.15 Principal Objective Evaluate a new in vivo method of titration of protamine sulfate. Secondary Objective Evaluate the impact of this method on the adequacy of heparin neutralization by measuring: 1. platelet count 2. postoperative bleeding 3. transfusion exposure a 4. incidence of heparin rebound

Timeline

Start

2008-06

Primary completion

2011-06

Completion

2011-06

Publications

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