THE EFFECT OF DEXTRAN ON MICROVASCULAR THROMBOSIS IN AN EXPERIMENTAL RABBIT MODEL

Although low molecular weight dextran is commonly utilized in clinical microsurgery, few experimental data are available documenting its eff icacy. Bilateral 2-mm arterial inversion grafts were constructed in th e femoral arteries of New Zealand White rabbits. The experimental grou p (n = 40 grafts) received a 5-day constant infusion of intravenous de xtran 40 at 2.1 ml/hour, and the control group (n = 50 grafts) receive d no infusion. Whereas 85 percent (34/40) of the dextran grafts were p atent at 1 week, only 48 percent (24/50) of the control grafts were pa tent (p = 0.0003). Scanning electron micrographs revealed a decrease i n both platelet and fibrin deposition in the patent dextran arterial i nversion grafts versus the patent control specimens. As a marked dimin ution in microvascular thrombosis was demonstrated at a clinically rel evant dose, the continued use of intravenous dextran 40 in clinical mi crosurgery is supported by this study.