RISK AND BENEFIT OF LOW SYSTEMIC HEPARINIZATION DURING OPEN-HEART OPERATIONS

Heparin surface-coated perfusion equipment with improved thromboresist ance was evaluated in 104 consecutive patients undergoing open heart o peration in a prospective, randomized trial with low versus full syste mic heparinization. Surgical procedures included coronary artery revas cularization 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 (1 5%) for low versus 5 of 50 patients (10%; NS) for full, left ventricul ar 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 patie nts (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 f or full (NS). Lowest activated coagulation time during perfusion was 2 55 +/- 75 seconds for low versus 537 +/- 205 seconds for full (p < 0.0 005). 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 occurr ed. Hospital mortality was 0 of 54 (0%) for low versus 1 of 50 patient s (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 ful l (p < 0.025). Amount of packed homologous red cells transfused (24 ho urs) was 300 +/- 354 mt 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% far low ve rsus 28.8% +/- 3.2% for full (NS) at 24 hours. Low systemic hepariniza tion during open heart operation results in reduced blood loss and tra nsfusion requirements.