title: Maintaining long-term vessel patency in microvascular surgery using tissue-type plasminogen activator.
abstract: The primary cause of free flap failure remains vascular thrombosis at the microanastomosis site. Four-hour local infusion of tissue plasminogen activator (t-PA) has been proved to effectively lyse thromboses in microvascular studies of animals; however, rethrombosis occurs once the infusion of t-PA has been terminated. The present study was designed to examine the efficacy of 48 hours of a continuous local t-PA infusion in maintaining long-term venous patency. Our previously described modified arterial inversion graft reanastomosed into the venous system was used in rabbits to form venous thrombi. Three mg of t-PA was infused over 48 hours in eleven rabbits. Seven of eleven grafts were patent at 48 hours and four remained patent at 1 week. In comparing the patency rates in this study with the overall patency rate using the modified arterial inversion graft model (1/22), there are statistically significant differences at both 48 hours (p less than 0.001) and 7 days (p less than 0.05). We conclude that lengthening the infusion time of t-PA may increase the long-term patency rate in this animal model.
authors.affiliation: Department of Otolaryngology, University of Minnesota, Minneapolis.
authors.forename: J E
authors.initials: JE
authors.lastname: Romano
authors.forename: M A
authors.initials: MA
authors.lastname: Biel
mesh_terms: D000818:Animals; D005263:Femoral Artery / Q000473:pathology / Q000601:surgery; D005342:Fibrinolysis; D006083:Graft Occlusion, Vascular / Q000473:pathology / Q000517:prevention & control*; D008866:Microsurgery; D011817:Rabbits; D013927:Thrombosis / Q000473:pathology / Q000517:prevention & control*; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D014654:Vascular Patency
chemical_list: D010959:Tissue Plasminogen Activator