Anticoagulation with prostaglandin E1 and unfractionated heparin during continuous venovenous hemofiltration.

Abstract

To determine the effect of two doses of prostaglandin E1 (PGE1, alprostadil) combined with unfractionated heparin on the hemofilter life-span and the coagulation profile during continuous venovenous hemofiltration. Prospective, randomized, controlled trial. Intensive care unit at a university-affiliated hospital. Twenty-four critically ill, mechanically ventilated patients with postoperative acute renal failure who require continuous venovenous hemofiltration. The patients were anticoagulated with 5 ng/kg/min PGE1 and 6 IU/kg/hr heparin or 20 ng/kg/min PGE1 and 6 IU/kg/hr heparin, injected into the extracorporeal circuit before the hemofilter. The life-span of 43 hemofilters was evaluated. They were used until extracorporeal line pressure exceeded 250 mm Hg, ultrafiltration rate decreased to 16 mL/min, or grossly visible extracorporeal clotting occurred. Blood was sampled from the afferent (prefilter) and efferent (postfilter) lines of the extracorporeal circuit. Platelet counts, in vitro platelet function, plasma concentrations of platelet factor 4, prothrombin fragment F1+2, thrombin-antithrombin complex, routine plasma coagulation tests, and hemodynamic profile were determined before and during hemofiltration. Hemofilter usage was significantly longer in patients anticoagulated with 20 ng/kg/min PGE1 (32 +/- 3 [SEM] hrs) than with 5 ng/kg/min PGE1 (22 +/- 3 hrs). In vitro bleeding parameters were significantly prolonged in postfilter blood in patients receiving 20 ng/kg/min PGE1. Prefilter, there was no antiplatelet activity in either group and platelet counts remained stable. No intra- or intergroup differences in plasma coagulation profile or hemodynamic parameters were detected. Extracorporeal administration of PGE1, combined with low-dose heparinization, inhibits platelet reactivity and preserves hemofilter life dose-dependently.