Resuscitation following severe, controlled hemorrhage associated with a 24 h delay to surgical intervention in swine using a hemoglobin based oxygen carrier as an oxygen bridge to definitive care

Summary Objectives To test our hypothesis that the hemoglobin based oxygen carrier HBOC-201 would have similar or superior efficacy to 6% hetastarch (HEX) as a pre-hospital ‘bridging' fluid for hemorrhagic shock when delay to definitive medical care is prolonged to 24h. Methods Twenty-four pigs were anesthetized, instrumented, given a soft tissue injury, and bled 55% estimated blood volume. Pigs were randomized to receive HBOC-201, HEX, or no resuscitation fluids (NON). At 4h post-injury, surgical sites were repaired and pigs were recovered from anesthesia. Animals were non-invasively monitored, administered blood for anemia or saline for hypotension at 24 and 48h, and monitored for 72h. Results Survival to 72h was 87.5% (7/8) in HBOC-201 and HEX pigs compared to 25% (2/8) in NON pigs ( p =0.01). Increased mean arterial pressure was observed in the HBOC-201 group ( p p p =0.002). Transcutaneous tissue oxygenation was higher with HBOC-201 (overall p =0.04, HBOC-201 versus HEX p 2 saturation, base deficit, and lactic acid. Hemoglobin was decreased with HEX (overall p p p >0.001). Conclusions HBOC-201 restored hemodynamics, maintained tissue oxygenation, and decreased blood transfusions in comparison to HEX in severe controlled HS with 24h delay to simulated hospital care. These results support the potential use of HBOC-201 as a bridging resuscitation fluid for HS.