The pharmacology of tissue oxygenation by biopure's hemoglobin-based oxygen carrier, Hemopure (HBOC-201).

Biopure's hemoglobin-based oxygen carrier, HBOC-201 (Hemopure), enhances oxygen transport by promoting both the convective and diffusive components of transport in the microcirculation. Convective transport is modified by HBOC-201 in three ways; (i) volume expansion promotes organ and tissue perfusion, (ii) the low viscosity of HBOC-201 improves flow to tissues, and (iii) oxygen delivery by HBOC Hb in the plasma is relatively insensitive to mechanisms regulating RBC distribution in the microcirculation. Diffusive oxygen transport is increased by the higher P50 compared with native RBC Hb which increases the off-loading of oxygen to tissues. Oxygen transport is also increased by reducing the diffusional barrier to oxygen transport associated with the plasma, in which oxygen is sparingly soluble. Biopure's HBOC solutions have been shown in vitro and in vivo to take up and off-load oxygen more efficiently than RBC Hb, and when added to blood can increase the efficiency of RBC oxygen transport.

HBOC-201 improves survival in a swine model of hemorrhagic shock and liver injury.

BACKGROUND: Blunt abdominal trauma that leads to hemorrhagic shock and cardiac arrest is almost always fatal in the prehospital setting. The current study investigated whether a hemoglobin-based oxygen carrier (HBOC-201) could maintain organ viability during an exsanguinating liver injury and allow for prolonged survival. This hypothesis was tested in a large animal model that simulated blunt abdominal trauma with major organ injury. METHODS: Swine underwent a liver crush, laceration and 50 ml/kg initial blood loss. The liver bled at 3 ml/kg per min during the resuscitation phase. No fluid (NF=6), hetastarch (HES=8), or HBOC-201 (HBOC=8) was given during the resuscitation phase. Swine alive 60 min after the initial injury underwent liver repair and 96 h observation. RESULTS: All HBOC swine survived 60 min versus none of the NF or HES swine (P<0.05). All HBOC swine survived 24 h and 7/8 survived 96 h with good functional recovery. CONCLUSIONS: HBOC resuscitation during liver bleeding in a swine model of hemorrhagic shock and liver injury allowed for 96 h survival. No fluid or HES in the same model was fatal.