The Power of Partial: Full Versus Partial Endovascular Aortic Occlusion in Traumatic Brain Injury

Resuscitative endovascular balloon occlusion of the aorta is an adjunct for hemorrhage control in trauma. Many patients requiring aortic occlusion also have concomitant traumatic brain injury (TBI). The combination of TBI and hemorrhagic shock is highly lethal. Aortic occlusion can increase mean arterial pressure, thus augmenting cerebral perfusion pressure in TBI patients. Hypotension and supraphysiologic hypertension can potentiate secondary insults in TBI. Endovascular aortic occlusion (EAO) can be done with full occlusion (FO) or partial occlusion (PO). PO allows for the titration of blood pressure, whereas FO can only have a binary effect on blood pressure. There is a paucity of data on the effects of FO and PO in patients with TBI. Therefore, we aim to evaluate the association of these two modalities with outcomes in TBI patients undergoing EAO.

This was an institutional review board-approved secondary retrospective analysis of the American Association for the Surgery of Trauma Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery registry that included all blunt trauma patients with Abbreviated Injury Scale head ≥ 1 and underwent EAO. We define severe TBI as head Abbreviated Injury Scale > 4. We compared FO and PO. Primary outcomes were systolic blood pressure (SBP) goal after EAO and mortality. Patients were considered to have SBP at goal if it was between > 90 and < 140 mmHg within 5 minutes after EAO. Secondary outcomes were length of stay, discharge Glasgow Coma Scale (GCS), discharge Glasgow Outcome Scale, disposition, rates of craniectomy, and complications.

147 patients were included in the final analysis. Of these, 97 underwent FO and 50 underwent PO. Demographics for all TBI patients undergoing EAO were age (40 ± 18), sex (32% female), mechanism of injury (93% blunt), injury severity score (42 ± 15), admission SBP (74 ± 46 mmHg), and admission GCS (6 ± 4). There was no significant difference in demographics between the two groups. Patients undergoing PO had significantly decreased transfusion of platelets (5.3 versus 2.5, P = 0.04) and administration of crystalloids (4 versus 1.5, P = 0.003). Patients with severe TBI who underwent PO met SBP goal significantly more often than patients who underwent FO (57.1 versus 83, P = 0.019). Higher rates of acute respiratory distress syndrome were seen in patients who underwent FO regardless of TBI severity. There was no significant difference in length of stay, mortality, discharge GCS, discharge Glasgow Outcome Scale, disposition, or rates of craniectomy between EAO groups.

PO enables better SBP titration and thereby can minimize secondary insult in TBI. PO is associated with lower rates of acute respiratory distress syndrome. EAO type, however, is not associated with differences in survival in TBI patients.