Reduced blood loss and transfusion requirements with low systemic heparinization: preliminary clinical results in coronary artery revascularization

Abstract

In coronary artery revascularization, low systemic heparinization wascompared to full systemic heparinization during perfusion with heparinsurface-coated cardiopulmonary bypass equipment. Twelve patients wererandomly assigned to two groups and perfused with low [activated clottingtime (ACT) greater than 180 s] or full (ACT greater than 480 s) systemicheparinization. A standard battery of blood samples was taken before theprocedure, after heparinization, and at regular intervals during and aftercardiopulmonary bypass. No differences were seen between the two groups inregard to age, body surface area, preoperative hematocrit, duration ofbypass, bypass hypothermia, cross- clamp time, and number of bypasses perpatient. However, there were more internal thoracic artery (ITA) grafts inthe group with low systemic heparinization (1.5 +/- 0.8 ITA grafts perpatient versus 0.8 +/- 0.4 ITA grafts per patient with full heparinization;p less than 0.05). The oxygenator gradient at the end of perfusion (beforeweaning) was 107 +/- 40 mmHg for low versus 110 +/- 10 mmHg for fullheparinization (difference not significant). The total amount of heparinused was 7200 +/- 1030 IU for low versus 51400 +/- 9700 IU for full (p lessthan 0.05). Postoperative hematocrit was 35.0 +/- 2.0% for low versus 24.7+/- 2.7% for full (p less than 0.05). Total chest tube drainage was 428 +/-153 ml/m2 for low versus 935 +/- 414 ml/m2 for full (p less than 0.05).Homologous transfusions of blood products were necessary in 3/6 patientsfor low versus 6/6 patients for full (p less than 0.10).(ABSTRACT TRUNCATEDAT 250 WORDS)