Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) for Use in Temporizing Intra-Abdominal and Pelvic Hemorrhage: Physiologic Sequelae and Considerations

PROGRESS OF RESUSCITATIVE ENDOVASCULAR BALLOON OCCLUSION OF THE AORTA IN PREHOSPITAL EMERGENCY TREATMENT FOR PELVIC FRACTURE

ABSTRACT

Pelvic fractures are severe traumatic injuries often accompanied by potentially fatal massive bleeding. Rapid control of hemorrhages in prehospital emergency settings is critical for improving outcomes in traumatic bleeding. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a promising technique for controlling active bleeding from pelvic fractures. By inserting a balloon catheter into the aorta, REBOA helps maintain blood flow to vital organs such as the brain and heart. This paper provides a comprehensive overview of the initial management of noncompressive trunk hemorrhage caused by pelvic fractures, introduces the technical principles and developments of REBOA, and explores its extensive application in prehospital emergency care. It delves into the operational details and outlines strategies for effectively managing potential complications. We aim to offer a theoretical framework for the future utilization of REBOA in managing uncontrollable hemorrhage associated with pelvic fractures in prehospital emergencies.

The Role of Resuscitative Endovascular Balloon Occlusion of the Aorta

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been utilized by trauma surgeons at the bedside for over a decade in both civilian and military settings. Both translational and clinical research suggest it is superior to resuscitative thoracotomy for specific patient populations. Technological advancements in recent years have significantly enhanced the safety profile of REBOA. Resuscitative balloon occlusion of the aorta has also swiftly found implementation in patients in shock from non-traumatic hemorrhage.

Complications associated with the use of resuscitative endovascular balloon occlusion of the aorta (REBOA): an updated review

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has become part of the arsenal to temporize patients in shock from severe hemorrhage. REBOA is used in trauma to prevent cardiovascular collapse by preserving heart and brain perfusion and minimizing distal hemorrhage until definitive hemorrhage control can be achieved. Significant side effects, including death, ischemia and reperfusion injuries, severe renal and lung damage, limb ischemia and amputations have all been reported. The aim of this article is to provide an update on complications related to REBOA. REBOA has emerged as a critical intervention for managing severe hemorrhagic shock, aiming to temporize patients and prevent cardiovascular collapse until definitive hemorrhage control can be achieved. However, this life-saving procedure is not without its challenges, with significant reported side effects. This review provides an updated overview of complications associated with REBOA. The most prevalent procedure-related complication is distal embolization and lower limb ischemia, with an incidence of 16% (range: 4-52.6%). Vascular and access site complications are also noteworthy, documented in studies with incidence rates varying from 1.2% to 11.1%. Conversely, bleeding-related complications exhibit lower documentation, with incidence rates ranging from 1.4% to 28.6%. Pseudoaneurysms are less likely, with rates ranging from 2% to 14%. A notable incidence of complications arises from lower limb compartment syndrome and lower limb amputation associated with the REBOA procedure. Systemic complications include acute kidney failure, consistently reported across various studies, with incidence rates ranging from 5.6% to 46%, representing one of the most frequently documented systemic complications. Infection and sepsis are also described, with rates ranging from 2% to 36%. Pulmonary-related complications, including acute respiratory distress syndrome and multisystem organ failure, occur in this population at rates ranging from 7.1% to 17.5%. This comprehensive overview underscores the diverse spectrum of complications associated with REBOA.

Resuscitative balloon occlusion of the aorta in the modern era: Expanding indications, optimal techniques, unresolved issues, and current results

Resuscitative endovascular balloon occlusion of the aorta has been used by trauma surgeons at the bedside for more than a decade in civilian and military settings. Translational and clinical research suggests it is superior to resuscitative thoracotomy for select patients. Clinical research suggests outcomes are superior in patients who received resuscitative balloon occlusion of the aorta compared with those who did not. Technology has advanced considerably in the past several years, leading to the improved safety profile and wider adoption of resuscitative balloon occlusion of the aorta. In addition to trauma patients, resuscitative balloon occlusion of the aorta has been rapidly implemented for patient with nontraumatic hemorrhage.

The role of REBOA in patients in traumatic cardiac arrest subsequent to hemorrhagic shock: a scoping review

PURPOSE

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a useful adjunct in treatment of patients in severe hemorrhagic shock. Hypothetically, REBOA could benefit patients in traumatic cardiac arrest (TCA) as balloon occlusion of the aorta increases afterload and may improve myocardial performance leading to return of spontaneous circulation (ROSC). This scoping review was conducted to examine the effect of REBOA on patients in TCA.

METHODS

This scoping review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Extension for Scoping Reviews (PRISMA-ScR) Statement. PubMed, EMBASE.com and the Web of Science Core Collection were searched. Articles were included if they reported any data on patients that underwent REBOA and were in TCA. Of the included articles, data regarding SBP, ROSC and survival were extracted and summarized.

RESULTS

Of 854 identified studies, 26 articles met criteria for inclusion. These identified a total of 785 patients in TCA that received REBOA (presumably less because of potential overlap in patients). This review shows REBOA elevates mean SBP in patients in TCA. The achievement of ROSC after REBOA deployment ranged from 18.2% to 67.7%. Survival to discharge ranged from 3.5% to 12.1%.

CONCLUSION

Overall, weak evidence is available on the use of REBOA in patients in TCA. This review, limited by selection bias, indicates that REBOA elevates SBP and may benefit ROSC and potentially survival to discharge in patients in TCA. Extensive further research is necessary to further clarify the role of REBOA during TCA.

A dumbbell rescue stent graft facilitates clamp-free repair of aortic injury in a porcine model

Objective

Noncompressible torso hemorrhage is a high-mortality injury. We previously reported improved outcomes with a retrievable rescue stent graft to temporize aortic hemorrhage in a porcine model while maintaining distal perfusion. A limitation was that the original cylindrical stent graft design prohibited simultaneous vascular repair, given the concern for suture ensnarement of the temporary stent. We hypothesized that a modified, dumbbell-shaped design would preserve distal perfusion and also offer a bloodless plane in the midsection, facilitating repair with the stent graft in place and improve the postrepair hemodynamics.

Methods

In an Institutional Animal Care and Use Committee-approved terminal porcine model, a custom retrievable dumbbell-shaped rescue stent graft (dRS) was fashioned from laser-cut nitinol and polytetrafluoroethylene covering and compared with aortic cross-clamping. Under anesthesia, the descending thoracic aorta was injured and then repaired with cross-clamping (n = 6) or dRS (n = 6). Angiography was performed in both groups. Operations were divided into phases: (1) baseline, (2) thoracic injury with either cross-clamp or dRS deployed, and (3) recovery, after which the clamp or dRS were removed. Target blood loss was 22% to simulate class II or III hemorrhagic shock. Shed blood was recovered with a Cell Saver and reinfused for resuscitation. Renal artery flow rates were recorded at baseline and during the repair phase and reported as a percentage of cardiac output. Phenylephrine pressor requirements were recorded.

Results

In contrast with cross-clamped animals, dRS animals demonstrated both operative hemostasis and preserved flow beyond the dRS angiographically. Recovery phase mean arterial pressure, cardiac output, and right ventricular end-diastolic volume were significantly higher in dRS animals (P = .033, P = .015, and P = .012, respectively). Whereas distal femoral blood pressures were absent during cross-clamping, among the dRS animals, the carotid and femoral MAPs were not significantly different during the injury phase (P = .504). Cross-clamped animals demonstrated nearly absent renal artery flow, in contrast with dRS animals, which exhibited preserved perfusion (P<.0001). Femoral oxygen levels (partial pressure of oxygen) among a subset of animals further confirmed greater distal oxygenation during dRS deployment compared with cross-clamping (P = .006). After aortic repair and clamp or stent removal, cross-clamped animals demonstrated more significant hypotension, as demonstrated by increased pressor requirements over stented animals (P = .035).

Conclusions

Compared with aortic cross-clamping, the dRS model demonstrated superior distal perfusion, while also facilitating simultaneous hemorrhage control and aortic repair. This study demonstrates a promising alternative to aortic cross-clamping to decrease distal ischemia and avoid the unfavorable hemodynamics that accompany clamp reperfusion. Future studies will assess differences in ischemic injury and physiological outcomes.

Clinical Relevance

Noncompressible aortic hemorrhage remains a high-mortality injury, and current damage control options are limited by ischemic complications. We have previously reported a retrievable stent graft to allow rapid hemorrhage control, preserved distal perfusion, and removal at the primary repair. The prior cylindrical stent graft was limited by the inability to suture the aorta over the stent graft owing to risk of ensnarement. This large animal study explored a dumbbell retrievable stent with a bloodless plane to allow suture placement with the stent in place. This approach improved distal perfusion and hemodynamics over clamp repair and heralds the potential for aortic repair while avoiding complications.

Systematic review to evaluate algorithms for REBOA use in trauma and identify a consensus for patient selection

Background

Patient selection for resuscitative endovascular balloon occlusion of the aorta (REBOA) has evolved during the last decade. A recent multicenter collaboration to implement the newest generation REBOA balloon catheter identified variability in patient selection criteria. The aims of this systematic review were to compare recent REBOA patient selection guidelines and to identify current areas of consensus and variability.

Methods

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we conducted a systematic review of clinical practice guidelines for REBOA patient selection in trauma. Published algorithms from 2015 to 2022 and institutional guidelines from a seven-center REBOA collaboration were compiled and synthesized.

Results

Ten published algorithms and seven institutional guidelines on REBOA patient selection were included. Broad consensus exists on REBOA deployment for blunt and penetrating trauma patients with non-compressible torso hemorrhage refractory to blood product resuscitation. Algorithms diverge on precise systolic blood pressure triggers for early common femoral artery access and REBOA deployment, as well as the use of REBOA for traumatic arrest and chest or extremity hemorrhage control.

Conclusion

Although our convenience sample of institutional guidelines likely underestimates patient selection variability, broad consensus exists in the published literature regarding REBOA deployment for blunt and penetrating trauma patients with hypotension not responsive to resuscitation. Several areas of patient selection variability reflect individual practice environments.

Level of evidence

Level 5, systematic review.

External Aortic Compression in Noncompressible Truncal Hemorrhage and Traumatic Cardiac Arrest: A Scoping Review

External aortic compression has been investigated as a treatment for non-compressible truncal haemorrhage in trauma patients. We sought to systematically gather and tabulate the available evidence around external aortic compression. We were specifically interested in its ability to achieve hemostasis and aid in resuscitation of traumatic arrest and severe shock and to consider physiological changes and adverse effects. A scoping review approach was chosen due to the highly variable existing literature. We were guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, using the specific extension for scoping reviews. Searches were done on PubMed and Scopus databases in October 2020. We found that a range of studies have investigated external aortic compression in a variety of settings, including case reports and small case series, porcine hemorrhage models and effects on healthy volunteers. External aortic compression for postpartum hemorrhage in a single center provided some evidence of effectiveness. Overall the level of evidence is limited, however, external aortic compression does appear able to achieve cessation of distal blood flow. Furthermore, it appears to improve many relevant physiological parameters in the setting of hypovolemic shock. Application for more than 60 minutes appears to cause increasingly problematic complications. In conclusion we find that the role of external aortic compression warrants further research. The intervention may have a role as a bridge to definitive treatment of noncompressible truncal haemorrahge.

Prehospital continuous vital signs predict need for resuscitative endovascular balloon occlusion of the aorta and resuscitative thoracotomy prehospital continuous vital signs predict resuscitative endovascular balloon occlusion of the aorta

BACKGROUND

Rapid triage and intervention to control hemorrhage are key to survival following traumatic injury. Patients presenting in hemorrhagic shock may undergo resuscitative thoracotomy (RT) or resuscitative endovascular balloon occlusion of the aorta (REBOA) as adjuncts to rapidly control bleeding. We hypothesized that machine learning along with automated calculation of continuously measured vital signs in the prehospital setting would accurately predict need for REBOA/RT and inform rapid lifesaving decisions.

METHODS

Prehospital and admission data from 1,396 patients transported from the scene of injury to a Level I trauma center via helicopter were analyzed. Utilizing machine learning and prehospital autonomous vital signs, a Bleeding Risk Index (BRI) based on features from pulse oximetry and electrocardiography waveforms and blood pressure (BP) trends was calculated. Demographics, Injury Severity Score and BRI were compared using Mann-Whitney-Wilcox test. Area under the receiver operating characteristic curve (AUC) was calculated and AUC of different scores compared using DeLong's method.

RESULTS

Of the 1,396 patients, median age was 45 years and 68% were men. Patients who underwent REBOA/RT were more likely to have a penetrating injury (24% vs. 7%, p < 0.001), higher Injury Severity Score (25 vs. 10, p < 0.001) and higher mortality (44% vs. 7%, p < 0.001). Prehospital they had lower BP (96 [70-130] vs. 134 [117-152], p < 0.001) and higher heart rate (106 [82-118] vs. 90 [76-106], p < 0.001). Bleeding risk index calculated using the entire prehospital period was 10× higher in patients undergoing REBOA/RT (0.5 [0.42-0.63] vs. 0.05 [0.02-0.21], p < 0.001) with an AUC of 0.93 (95% confidence interval [95% CI], 0.90-0.97). This was similarly predictive when calculated from shorter periods of transport: BRI initial 10 minutes prehospital AUC of 0.89 (95% CI, 0.83-0.94) and initial 5 minutes AUC of 0.90 (95% CI, 0.85-0.94).

CONCLUSION

Automated prehospital calculations based on vital sign features and trends accurately predict the need for the emergent REBOA/RT. This information can provide essential time for team preparedness and guide trauma triage and disaster management.

LEVEL OF EVIDENCE

Therapeutic/care management, Level IV.