Resuscitative endovascular balloon occlusion of the aorta for major abdominal venous injury in a porcine hemorrhagic shock model.

Background: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a rescue maneuver for unstable patients with noncompressible hemorrhage below the diaphragm. The efficacy of REBOA in the setting a major abdominal venous injury is unknown. Our objective was to examine the use of REBOA in a large animal model of major abdominal venous injury and characterize any impact on the hemodynamics, rate and volume of hemorrhage, and survival.

Methods: Ten swine (35-55 kg) underwent a controlled and validated hemorrhage and ischemia/reperfusion injury protocol to produce shock physiology. Animals were randomly assigned to a control arm (N = 5) or a treatment (REBOA) arm (N = 5). An injury was then created in the common iliac vein. Bleeding was allowed for 60 seconds and the balloon was then inflated in the REBOA arm. Hemodynamics were recorded for 45 minutes or until death. Blood loss was verified post-mortem and bleeding rate calculated.

Results: All animals demonstrated shock physiology at the time of randomization. There were no differences between control versus REBOA animals in baseline mean arterial pressure (42 vs. 50), pH (7.29 vs. 7.26), lactate (6.19 vs. 6.26), or INR (1.2 vs. 1.3, all p = NS). REBOA animals demonstrated immediate improvements in mean arterial pressure (50.6 vs. 97.2, p = 0.04). The mean survival time was 4.1 minutes for controls (100% died) versus 40.1 minutes for REBOA (p < 0.01). There was no difference in total blood loss (mean 630 mL for both). The rate of bleeding was significantly lower in the REBOA animals (control 197 mL/min vs. REBOA 14 mL/min, p = 0.02).

Conclusion: In the setting of an abdominal venous injury, REBOA improved hemodynamics and lengthened survival time. Blood loss was similar between groups but the rate of bleeding was markedly decreased with REBOA. REBOA appears effective for central venous injuries and provides a sustained period of stabilization and window for surgical intervention.