Titratable partial aortic occlusion: Extending Zone I endovascular occlusion times.

Background: Extending the time to definitive hemorrhage control in noncompressible torso hemorrhage (NCTH) is of particular importance in the battlefield where transfer times are prolonged and NCTH remains the leading cause of death. While resuscitative endovascular balloon occlusion of the aorta is widely practiced as an initial adjunct for the management of NCTH, concerns for ischemic complications after 30 minutes of compete aortic occlusion deters many from zone 1 deployment. We hypothesize that extended zone 1 occlusion times will be enabled by novel purpose-built devices that allow for titratable partial aortic occlusion.

Methods: This is a cross-sectional analysis describing pREBOA-PRO zone 1 deployment characteristics at seven level 1 trauma centers in the United States and Canada (March 30, 2021, and June 30, 2022). To compare patterns of zone 1 aortic occlusion, the AORTA registry was used. Data were limited to adult patients who underwent successful occlusion in zone 1 (2013-2022).

Results: One hundred twenty-two patients pREBOA-PRO patients were included. Most catheters were deployed in zone 1 (n = 89 [73%]) with a median zone 1 total occlusion time of 40 minutes (interquartile range, 25-74). A sequence of complete followed by partial occlusion was used in 42% (n = 37) of zone 1 occlusion patients; a median of 76% (interquartile range, 60-87%) of total occlusion time was partial occlusion in this group. As was seen in the prospectively collected data, longer median total occlusion times were observed in the titratable occlusion group in AORTA compared with the complete occlusion group.

Conclusion: Longer zone 1 aortic occlusion times seen with titratable aortic occlusion catheters appear to be driven by the feasibility of controlled partial occlusion. The ability to extend safe aortic occlusion times may have significant impact to combat casualty care where exsanguination from NCTH is the leading source of potentially preventable deaths.

Level Of Evidence: Therapeutic/Care Management; Level IV.