Zones matter: Hemodynamic effects of zone 1 vs zone 3 resuscitative endovascular balloon occlusion of the aorta placement in trauma patients.

Background: Resuscitative endovascular balloon occlusion of the aorta (REBOA) has emerged as a therapy for hemorrhagic shock to limit ongoing bleeding and support proximal arterial pressures. Current REBOA algorithms recommend zone selection based on suspected anatomic location of injury rather than severity of shock. We examined the effects of Zone 1 versus Zone 3 REBOA in patients enrolled in the American Association for the Surgery of Trauma Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery (AORTA) Registry.

Methods: The prospective observational AORTA Registry was queried from November 2013 to November 2017. Patients who received REBOA were included if their initial systolic blood pressure (SBP) was less than 90 mmHg upon arrival and they were not receiving cardiopulmonary resuscitation.

Results: There were 762 patients recorded in the AORTA database during the study period. Of these, 245 underwent REBOA and 99 patients met inclusion criteria. The initial balloon position was Zone 1 in 55 patients, Zone 3 in 36 patients, and unknown or Zone 2 in 8 patients. The change in proximal SBP was greater after REBOA in the Zone 1 group compared to the Zone 3 group (58 ± 4 mmHg vs 41 ± 4 mmHg, P = 0.008). The zone of occlusion was significantly associated with the change in proximal SBP in a linear regression analysis which included initial SBP, Glasgow Coma Scale score, and Injury Severity Score (Coefficient 26.82, 95% Confidence Interval 8.11-45.54, P = 0.006).

Conclusions: In the hypotensive trauma patient, initial Zone 1 REBOA provides maximal hemodynamic support. Algorithms recommending initial Zone 3 placement for hypotensive trauma patients should be reconsidered.