Risk and benefit of low systemic heparinization during open heart operations

Abstract

Heparin surface-coated perfusion equipment with improved thromboresistance was evaluated in 104 consecutive patients undergoing open heart operation in a prospective, randomized trial with low versus full systemic heparinization. Surgical procedures included coronary artery revascularization in 47 of 54 (87%) for low versus 44 of 50 patients (88%; not significant [NS]) for full, valve repair/replacement in 8 of 54 (15%) for low versus 5 of 50 patients (10%; NS) for full, left ventricular aneurysm repair in 1 of 54 (2%) for low versus 2 of 50 patients (4%; NS) for full, and other in 3 of 54 (6%) for low versus 3 of 50 patients (6%; NS) for full. Cross-clamp time was 39.2 ± 10.7 minutes for low versus 39.5 ± 10.5 minutes for full (NS). Cardiopulmonary bypass time was 68.6 ± 20.1 minutes for low versus 69.3 ± 16.6 minutes for full (NS). Lowest activated coagulation time during perfusion was 255 ± 75 seconds for low versus 537 ± 205 seconds for full ( p < 0.0005). In the low group, the target activated coagulation time of more than 180 seconds was not reached during perfusion in 4 of 54 patients (7%), the lowest value being 164 seconds. No oxygenator failure occurred. Hospital mortality was 0 of 54 (0%) for low versus 1 of 50 patients (2%) for full (NS). Bleeding required surgical revision in 0 of 54 (0%) for low versus 4 of 50 patients (8%) for full ( p = 0.05). Drainage (24 hours) was 790 ± 393 mL for low versus 1,039 ± 732 mL for full ( p < 0.025). Amount of packed homologous red cells transfused (24 hours) was 300 ± 354 mL for low versus 957 ± 596 mL for full ( p < 0.0005). Baseline hematocrit of 43.3% ± 3.7% for low versus 43.0% ± 3.9% (NS) for full before operation moved to 28.9% ± 3.2% for low versus 28.8% ± 3.2% for full (NS) at 24 hours. Low systemic heparinization during open heart operation results in reduced blood loss and transfusion requirements.