Administration of polymerized bovine hemoglobin improves survival in a ratmodel of traumatic shock

The ability of purified and modified hemoglobin solutions to expand blood v olume and act as oxygen and carbon dioxide transporters with no apparent to xic side effects has lead to an increased interest in their utilization in shock conditions. Although hemoglobin solutions have been shown to provide beneficial effects in endotoxic and hemorrhagic shock, they have not been s tudied in whole body traumatic injury. We investigated the effects of a pol ymerized bovine hemoglobin solution (HBOC-201) in a rat model of traumatic shock. Pentobarbital-anesthetized rats subjected to Noble-Collip drum traum a developed a shock state characterized by marked hypotension, a survival t ime of 102 +/- 20 min, significant increases in intestinal myeloperoxide (M PO) activity and splanchnic vascular endothelial dysfunction characterized by an impaired vasorelaxation of the superior mesenteric artery (SMA) to en dothelium-dependent vasodilators. Traumatized rats were treated with HBOC-2 01 or an equal volume of vehicle corresponding to 5, 10 or 15% of the calcu lated blood volume. Treatment with HBOC-201 10 min posttrauma prolonged sur vival, normalized mean arterial blood pressure and attenuated endothelial d ysfunction of the SMA. However, administration of HBOC-201 failed to signif icantly attenuate increases in intestinal MPO activity following trauma. No beneficial effects were observed with the administration the vehicle. Thes e data indicate the HBOC-201 exerts significant beneficial effects in traum atic shock states by normalizing system blood pressure and attenuating vasc ular endothelial dysfunction. HBOC-201 may serve as a useful adjunctive age nt in the early treatment of trauma. (C)1999 Prous Science. All rights rese rved.