Self-expanding foam versus preperitoneal packing for exsanguinating pelvic hemorrhage

BACKGROUND: Mortality for pelvic fracture patients presenting with hemorrhagic shock ranges from 21% to 57%. The objective of this study was to develop a lethal and clinically relevant pelvic hemorrhage animal model with and without bony fracture for evaluating therapeutic interventions. ResQFoam is a self-expanding foam that has previously been described to significantly decrease mortality in large-animal models of abdominal exsanguination. We hypothesized that administration of ResQFoam into the preperitoneal space could decrease mortality in exsanguinating pelvic hemorrhage. METHODS: Two pelvic hemorrhage models were developed using noncoagulopathic swine. Pelvic hemorrhage model 1: bilateral, closed-cavity, major vascular retroperitoneal hemorrhage without bony pelvic fracture. After injury, animals received no treatment (control, n = 10), underwent preperitoneal packing using laparotomy pads (n = 11), or received ResQFoam (n = 10) injected into the preperitoneal space. Pelvic hemorrhage model 2: unilateral, closed-cavity, retroperitoneal hemorrhage injury (with intraperitoneal communication) combined with complex pelvic fracture. After injury, animals received resuscitation (control, n = 12), resuscitation with preperitoneal packing (n = 10) or with ResQFoam injection (n = 10) into the preperitoneal space. RESULTS: For model 1, only ResQFoam provided a significant survival benefit. The median survival times were 50 minutes and 67 minutes for preperitoneal packing and ResQFoam, compared with 6 minutes with controls ( p = 0.002 and 0.057, respectively). Foam treatment facilitated hemodynamic stabilization and resulted in significantly less hemorrhage (21.5 ± 5.3 g/kg) relative to controls (31.6 ± 5.0 g/kg, p < 0.001) and preperitoneal packing (32.7 ± 5.4 g/kg, p < 0.001). For model 2, both ResQFoam and preperitoneal packing resulted in significant survival benefit compared with controls. The median survival times were 119 minutes and 124 minutes for the preperitoneal packing and ResQFoam groups, compared with 4 minutes with controls ( p = 0.004 and 0.013, respectively). CONCLUSION: Percutaneous injection of ResQFoam into the preperitoneal space improved survival relative to controls, and similar survival benefit was achieved compared with standard preperitoneal pelvic packing. The technology has potential to augment the armamentarium of tools to treat pelvic hemorrhage.