Prolonged partial occlusion of the aorta in a swine model of hemorrhage and traumatic brain injury does not worsen the brain lesion, but significantly impacts hemodynamic stability

Abstract Introduction Hemorrhagic shock (HS) and traumatic brain injury (TBI) are leading causes of death in trauma. It has been shown that a novel partially occluding resuscitative endovascular balloon occlusion of the aorta device (p-REBOA) can be deployed in the thoracic aorta for up to 2 hours with minimal downstream ischemia. However, the impact of partial occlusion on the injured brain has not been studied. We hypothesized that the use of the p-REBOA in a model of TBI and HS would not worsen the brain lesion size. Methods Yorkshire, female swine (40-45 kg; n = 22) were subjected to controlled cortical impact TBI and 40% blood volume loss. After 1-hour of shock, they were randomized to either: 1) placement of p-REBOA for two hours (p-REBOA group), or 2) no p-REBOA (control). Brain lesion size, survival rates, resuscitation requirements, and key laboratory values were used to compare the groups. Results Nineteen animals survived to the end of the experiment, with all three deaths in the p-REBOA group (p = 0.1336). The brain lesion size was similar between the groups (mean p-REBOA volume vs. control: 3690.93 ± 1027.21 mm 3 and 2961.32 ± 807.31 mm 3 respectively, p = 0.1245). The p-REBOA group showed more severe tissue ischemia, as defined by worse peak lactic acidosis (p < 0.000001). All animals in the p-REBOA group required vasopressor support during the critical care period compared to one in the control group (p = 0.0001). Conclusion Prolonged partial occlusion of the thoracic aorta in a combined model of hemorrhagic shock and TBI results in significant hemodynamic instability, without an increase in the brain lesion size.