Effects of albumin coating of knitted Dacron grafts on transinterstitial blood loss and tissue ingrowth and incorporation

Transinterstitial blood loss at implantation and the degree of graft incorporation and inner capsule thickening was compared in serial explants of albumin-coated Dacron versus blood preclotted Dacron grafts in the canine thoracoabdominal aortic position (8 mm internal diameter × 30 cm length). The coated grafts were Bard DeBakey Vasculour II knitted Dacron prostheses impregnated with carbodiimide-cross-linked human albumin. Control grafts were otherwise identical and preclotted with the recipients' whole blood before heparinization during surgery. Transinterstitial blood loss after establishing flow was measured by weighing sponges wrapped around the grafts. Albumin pretreatment resulted in significantly less median blood loss (5.1 g versus 11 g, P = 0.04; Mann-Whitney rank sum test). Grafts were explanted at 1 week, 4 weeks, 10 weeks, and 20 weeks. Patency was 100% in both groups. Graft incorporation at explantation was graded by the surgeon as: 1 = none, 2 = minimal, 3 = moderate, or 4 = extensive. No significant differences were noted at any time period. Inner capsule thickness measurements were made every 2.5 mm along the length of all explants. Grafts explanted at 1 week displayed no inner capsules. By 20 weeks, median inner capsule thickness was significantly less in albumin-coated grafts (190 μm versus 235 μm; P