Recent trauma studies have shown a trend in how severe bleeding is managed when performing resuscitative endovascular balloon occlusion of the aorta (REBOA). While complete aortic occlusion remains a cornerstone of this technique, partial REBOA (p-REBOA) has emerged as a compelling adjunct. Rather than fully blocking blood flow, p-REBOA allows controlled perfusion to critical organs while still managing hemorrhage—a balance that could reduce ischemic complications, especially when prolonged occlusion times are required. Mastering partial occlusion techniques has become a useful tool in modern trauma care.
The Benefits of Partial REBOA
Improved Physiologic Outcomes
Studies show that p-REBOA patients may have improved outcomes compared to those undergoing complete occlusion. These benefits include better maintenance of organ perfusion, reduced metabolic disturbances, lower rates of post-procedure ischemia/reperfusion complications, and improved tissue preservation. Research highlights that p-REBOA allows for effective hemorrhage control while maintaining higher tissue oxygenation levels and better metabolic stability compared to complete occlusion. This controlled perfusion minimizes ischemia and the associated buildup of metabolic byproducts such as lactate. By avoiding full occlusion, p-REBOA reduces the risk of severe acidosis and mitigates the physiological stress on both the tissue distal to the occlusion and those subjected to reperfusion when blood flow is restored. Controlled hypoperfusion below the balloon can also minimize the risk of sudden reperfusion injury. These methods help sustain oxygen delivery while preventing the cascade of metabolic disruptions typically seen with complete REBOA occlusion for prolonged periods.
The Challenges of Implementation
Technique
A 2023 study done by Power and colleagues focused on evaluating the COBRA-OS® device in the context of partial resuscitative endovascular balloon occlusion of the aorta (p-REBOA). The study highlighted significant issues with traditional REBOA devices, particularly their inability to titrate easily to partial occlusion. The COBRA-OS® device was tested for its ability to achieve and maintain precise control of distal mean arterial pressure.
The findings from the study emphasized how the COBRA-OS® allows for small, incremental adjustments in balloon volume. This precision provides better control of blood flow, reducing risks associated with sudden pressure shifts and ensuring more consistent distal perfusion. These capabilities help maintain a safer, more stable environment for trauma care patients, suggesting that the COBRA-OS® may be a valuable advancement over traditional REBOA technologies not just by being the smallest aortic occlusion device available.
Learning Curve and Training Requirements
P-REBOA takes more than just knowing how to use the device. Surgeons need to understand blood flow dynamics, manage organ perfusion, and handle each patient’s unique anatomy. These skills only come through hands-on experience with multiple cases. Yet most centers are left to develop their own standards and protocols. For smaller hospitals especially, the challenge is stark – when you only see a handful of cases each year, keeping skills sharp becomes nearly impossible. In these circumstances, a strategy of intermittent occlusion at certain pre-determined intervals may be easier to implement than p-REBOA.
Research Limitations
The research on p-REBOA tells an incomplete story. Most studies come from single hospitals working with small groups of patients and are heavily industry-biased. Every trauma center handles partial occlusion differently – from timing to techniques. This variation makes it nearly impossible to run the kind of large studies we need. Basic questions remain unanswered: optimal distal pressure levels, safe duration limits, and the most effective ways to restore blood flow to avoid the ischemia-reperfusion phenomenon. We also don’t know the applications where p-REBOA might not be an optimal strategy. For instance, when it is used in Zone 3 prophylactically for placenta accreta spectrum, it doesn’t make sense theoretically, but it is being marketed for these reasons.
Future Directions and Research Priorities
We still have much to learn about REBOA procedures, and research is still needed to establish evidence-based guidelines that can make REBOA more reliable and widely used. That said, devices like the COBRA-OS® are showing great promise. Their design and functionality could redefine how we approach trauma care by allowing for more controlled and precise partial REBOA. However, success will depend on continued refinement of the technology, a deeper understanding of the benefits, and the development of practical treatment protocols based on solid research evidence.
References:
- Power A, et al. “Cushioned on the way up, controlled on the way down during REBOA.” J Trauma Acute Care Surg (2023) https://tsaco.bmj.com/content/7/1/e000948
- Johnson MA, Neff LP, Williams TK, DuBose JJ; EVAC Study Group. Partial resuscitative balloon occlusion of the aorta (P-REBOA): Clinical technique and rationale. J Trauma Acute Care Surg. 2016;81(5 Suppl 2 Proceedings of the 2015 Military Health System Research Symposium):S133-S137. doi:10.1097/TA.0000000000001146 https://www.researchgate.net/publication/303635243_Partial_Resuscitative_Balloon_Occlusion_of_the_AORTA_P-REBOA_Clinical_Technique_and_Rationale
- Gondek S, Hamblin S, Raley J, et al. A PROMPT Update on Partial REBOA: Initial Clinical Data and Overview of the DoD-Funded Partial REBOA Outcomes Multicenter ProspecTive (PROMPT) Study. Mil Med. 2024;189(Suppl 3):284-290. doi:10.1093/milmed/usae095 https://pubmed.ncbi.nlm.nih.gov/39160869/
- Fontenelle Ribeiro Junior MA, Salman SM, Al-Qaraghuli SM, et al. Complications associated with the use of resuscitative endovascular balloon occlusion of the aorta (REBOA): an updated review. Trauma Surg Acute Care Open. 2024;9(1):e001267. Published 2024 Feb 7. doi:10.1136/tsaco-2023-001267 https://tsaco.bmj.com/content/9/1/e001267
