Use of resuscitative endovascular balloon occlusion of the aorta (REBOA) for trauma and its performance in Japan over the past 18 years: a nationwide descriptive study.

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been used to control massive hemorrhages. Although there is no consensus on the efficacy of REBOA, it remains an option as a bridging therapy in non-trauma centers where trauma surgeons are not available. To better understand the current landscape of REBOA application, we examined changes in its usage, target population, and treatment outcomes in Japan, where immediate hemostasis procedures sometimes cannot be performed. METHODS: This retrospective observational study used the Japan Trauma Data Bank data. All cases in which REBOA was performed between January 2004 and December 2021 were included. The primary outcome was the in-hospital mortality rate. We analyzed mortality trends over time according to the number of cases, number of centers, severity of injury, and overall and subgroup mortality associated with REBOA usage. We performed a logistic analysis of mortality trends over time, adjusting for probability of survival based on the trauma and injury severity score. RESULTS: Overall, 2557 patients were treated with REBOA and were deemed eligible for inclusion. The median age of the participants was 55 years, and male patients constituted 65.3% of the study population. Blunt trauma accounted for approximately 93.0% of the cases. The number of cases and facilities that used REBOA increased until 2019. While the injury severity score and revised trauma score did not change throughout the observation period, the hospital mortality rate decreased from 91.3 to 50.9%. The REBOA group without severe head or spine injuries showed greater improvement in mortality than the all-patient group using REBOA and all-trauma patient group. The greatest improvement in mortality was observed in patients with systolic blood pressure ≥ 80 mmHg. The adjusted odds ratios for hospital mortality steadily declined, even after adjusting for the probability of survival. CONCLUSIONS: While there was no significant change in patient severity, mortality of patients treated with REBOA decreased over time. Further research is required to determine the reasons for these improvements in trauma care.

Vascular access complications associated with resuscitative endovascular balloon occlusion of the aorta in adult trauma patients: A systematic review and meta-analysis.

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is gaining popularity worldwide for managing hypotensive trauma patients. Vascular access complications related to REBOA placement have been reported, with some cases resulting in permanent morbidity. We aim to capitalize on the increase in literature to further describe and estimate the incidence of REBOA-associated vascular access complications in adult trauma patients. METHODS: We searched Medline, EMBASE, Scopus, and CINAHL for studies reporting vascular access complications of REBOA in adult trauma patients from inception to October 14, 2021. Studies reporting data from adult trauma patients who underwent REBOA insertion were eligible. Exclusion criteria included patients 15 years and younger, nontrauma patients, non-REBOA use, non-vascular access complications and patient duplication. Study data was abstracted using the PRISMA checklist and verified independently by three reviewers. Meta-analysis of proportions was performed using a random effects model with Freeman-Turkey double-arcsine transformation. Post hoc meta-regression by year of publication, sheath-size, and geographic region was also performed. The incidence of vascular access complications from REBOA insertion was the primary outcome of interest. Subgroup analysis was performed by degree of bias, sheath size, technique of vascular access, provider specialty, geographical region, and publication year. RESULTS: Twenty-four articles were included in the systematic review and the meta-analysis, for a total of 675 trauma patients who underwent REBOA insertion. The incidence of vascular access complications was 8% (95% confidence interval, 5%-13%). In post hoc meta-regression adjusting for year of publication and geographic region, the use of a smaller (7-Fr) sheath was associated with a decreased incidence of vascular access complications (odds ratio, 0.87; 95% confidence interval, 0.75-0.99; p = 0.046; R 2 = 35%; I 2 = 48%). CONCLUSION: This study provides a benchmark for quality of care in terms of vascular access complications related to REBOA insertion in adult trauma patients. Smaller sheath size may be associated with a decrease in vascular access complications. LEVEL OF EVIDENCE: Systematic Review and Meta-Analysis; Level III.

Critical systolic blood pressure threshold for endovascular aortic occlusion-A multinational analysis to determine when to place a REBOA.

BACKGROUND: Systolic blood pressure (SBP) is a potential indicator that could guide when to use a resuscitative endovascular balloon occlusion of the aorta (REBOA) in trauma patients with life-threatening injuries. This study aims to determine the optimal SBP threshold for REBOA placement by analyzing the association between SBP pre-REBOA and 24-hour mortality in severely injured hemodynamically unstable trauma patients. METHODS: We performed a pooled analysis of the aortic balloon occlusion (ABO) trauma and AORTA registries. These databases record the details related to the use of REBOA and include data from 14 countries worldwide. We included patients who had suffered penetrating and/or blunt trauma. Patients who arrived at the hospital with a SBP pre-REBOA of 0 mm Hg and remained at 0 mm Hg after balloon inflation were excluded. We evaluated the impact that SBP pre-REBOA had on the probability of death in the first 24 hours. RESULTS: A total of 1,107 patients underwent endovascular aortic occlusion, of these, 848 met inclusion criteria. The median age was 44 years (interquartile range [IQR], 27-59 years) and 643 (76%) were male. The median injury severity score was 34 (IQR, 25-45). The median SBP pre-REBOA was 65 mm Hg (IQR, 49-88 mm Hg). Mortality at 24 hours was reported in 279 (32%) patients. Math modeling shows that predicted probabilities of the primary outcome increased steadily in SBP pre-REBOA below 100 mm Hg. Multivariable mixed-effects analysis shows that when SBP pre-REBOA was lower than 60 mm Hg, the risk of death was more than 50% (relative risk, 1.5; 95% confidence interval, 1.17-1.92; p = 0.001). DISCUSSION: In patients who do not respond to initial resuscitation, the use of REBOA in SBPs between 60 mm Hg and 80 mm Hg may be a useful tool in resuscitation efforts before further decompensation or complete cardiovascular collapse. The findings from our study are clinically important as a first step in identifying candidates for REBOA. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level IV.

Systematic Review and Meta-Analysis of Nonoperative Management for SVS Grade II Blunt Traumatic Aortic Injury.

BACKGROUND: Society for Vascular Surgery (SVS) grade II blunt traumatic aortic injury is defined as intramural hematoma with or without external contour abnormality. It is uncertain whether this aortic injury pattern should be treated with endovascular stent-grafting or nonoperative measures. Since the adoption of the SVS Guidelines on endovascular repair of blunt traumatic aortic injury, the practice pattern for management of grade II injuries has been heterogenous. The objective of the study was to report natural history outcomes of grade II blunt traumatic aortic injury. METHODS: A systematic review of published traumatic aortic injury studies was performed. Online database searches were current to November 2022. Eligible studies included data on aortic injuries that were both managed nonoperatively and classified according to the SVS 2011 Guidelines. Data points on all-cause mortality, aorta-related mortality and early aortic intervention were extracted and underwent meta-analysis. The methodology was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidance. RESULTS: Thirteen studies were included in the final analysis with a total of 204 cases of SVS grade II blunt traumatic aortic injury treated nonoperatively. The outcomes rates were estimated at 10.4% (95% confidence interval [CI] 6.7%-14.9%) for all-cause mortality, 2.9% (95% CI 1.1%-5.7%) for aorta-related mortality, and 3.3% (95% CI 1.4%-6.2%) for early aortic intervention. The studies included in the analysis were of fair quality with a mean Downs and Black score 15 (±1.8). CONCLUSIONS: Grade II blunt traumatic aortic injury follows a relatively benign course with few instances of aortic-related mortality. Death in the setting of this injury pattern is more often attributable to sequelae of multisystem trauma and not directly related to aortic injury. The current data support nonoperative management and imaging surveillance for grade II blunt traumatic aortic injury instead of endovascular repair. Longer-term effects on the aorta at the site of injury are unknown.

Management of Pediatric Aortic Pseudoaneurysm Due to Penetrating Trauma.

Due to the increasing frequency of pediatric penetrating trauma, pediatric surgeons need to be prepared to evaluate and manage complex penetrating injuries. In this report, we discuss the endovascular management of a traumatic aortic pseudoaneurym and subsequent bullet retrieval following penetrating chest trauma in a child. The key to successful management included multidisciplinary decision making and use of an expandable covered stent generally used for management of aortic coarctation.

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.

Early Versus Delayed Thoracic Endovascular Aortic Repair for Blunt Thoracic Aortic Injury: A Propensity Score-Matched Analysis.

OBJECTIVE: We examined early (≤24 h) versus delayed (>24 h) thoracic endovascular aortic repair (TEVAR) for blunt thoracic aortic injury (BTAI), taking the aortic injury severity into consideration. BACKGROUND: Current trauma surgery guidelines recommend delayed TEVAR following BTAI. However, this recommendation was based on small studies, and specifics regarding recommendation strategies based on aortic injury grades are lacking. METHODS: Patients undergoing TEVAR for BTAI in the American College of Surgeons Trauma Quality Improvement Program between 2016 and 2019 were included and then stratified into 2 groups (early: ≤24 h vs. delayed: >24 h). In-hospital outcomes were compared after creating 1:1 propensity score-matched cohorts, matching for demographics, comorbidities, concomitant injuries, additional procedures, and aortic injury severity based on the acute aortic syndrome (AAS) classification. RESULTS: Overall, 1339 patients were included, of whom 1054(79%) underwent early TEVAR. Compared with the delayed group, the early group had significantly less severe head injuries (early vs delayed; 25% vs 32%; P =0.014), fewer early interventions for AAS grade 1 occurred, and AAS grade 3 aortic injuries often were intervened upon within 24 hours (grade 1: 28% vs 47%; grade 3: 49% vs 23%; P <0.001). After matching, the final sample included 548 matched patients. Compared with the delayed group, the early group had a significantly higher in-hospital mortality (8.8% vs 4.4%, relative risk: 2.2, 95% CI: 1.1-4.4; P =0.028), alongside a shorter length of hospital stay (5.0 vs 10 days; P =0.028), a shorter intensive care unit length of stay (4.0 vs 11 days; P <0.001) and fewer days on the ventilator (4.0 vs 6.5 days; P =0.036). Furthermore, regardless of the higher risk of acute kidney injury in the delayed group (3.3% vs 7.7%, relative risk: 0.43, 95% CI: 0.20-0.92; P =0.029), no other differences in in-hospital complications were observed between the early and delayed group. CONCLUSION: In this propensity score-matched analysis, delayed TEVAR was associated with lower mortality risk, even after adjusting for aortic injury grade.

Tandem use of gastroesophageal resuscitative occlusion of the aorta followed by resuscitative endovascular balloon occlusion of the aorta in a lethal liver laceration model.

BACKGROUND: Gastroesophageal resuscitative occlusion of the aorta (GROA) has been shown effective in creating zone II aortic occlusion capable of temporarily improving survival in animal models of lethal noncompressible torso hemorrhage. In this study, tandem application of GROA transitioning to resuscitative endovascular balloon occlusion of the aorta (REBOA) is explored to demonstrate feasibility as a potential point-of-injury bridge to more advanced care, using a swine model of lethal abdominal hemorrhage. METHODS: Swine (n = 19) were anesthetized, instrumented, and subjected to a combination of controlled and uncontrolled hemorrhage from a grade-V liver laceration. Animals were designated as intervention (n = 9; GROA to REBOA) or control (n = 10), for 60 minutes. Following intervention, devices were deactivated, and animals received blood and crystalloid resuscitation. Animals were monitored for 4 hours. RESULTS: Injury resulted in onset of class IV shock in all animals with a mean arterial pressure (SD) of 24.5 (4.11) mm Hg at the start of intervention. Nine of 10 controls died during the intervention period with a median (interquartile) survival time of 8.5 (9.25) minutes. All animals receiving the intervention survived both the 60-minute intervention period demonstrating a significant survival improvement ( p = 0.0007). Transition from GROA to REBOA was successful in all animals with a transition time ranging from 30 to 90 seconds. Mean arterial pressure significantly improved in animals receiving GROA to REBOA for the duration of intervention, regardless of the method of aortic occlusion, with a range of 70.9 (16.04) mm Hg to 101.1 (15.3) mm Hg. Additional hemodynamics, metrics of shock, and oxygenation remained stable during intervention. CONCLUSION: Less invasive technologies such as GROA may present an opportunity to control noncompressible torso hemorrhage more rapidly, with a subsequent transition to more advanced care such as REBOA.

Management of Penetrating Injury to the Esophagus Into the Aorta by a Fishbone.

A 66-year-old man was reported to have persistent chest pain for 4 hours after accidentally swallowing a fishbone. An isolated esophageal foreign body (EFB) was suspected in the community hospital. In our center, an emergency chest CT scan revealed an EFB in the upper part of the esophagus of the patient which penetrated the left esophageal wall as well as the distal aortic arch. However, the experience of the treatment strategy for this lesion is still not enough available. Considering the surgical trauma and the risk associated with advanced age of the patient, the option for open surgery was waived. In addition, there was also a risk of sudden death due to aortic rupture that could occur after direct removal of the fishbone. Therefore, emergency thoracic endovascular aortic repair was performed and the fishbone was removed under an endoscope. The patient successfully pulled through without any discomfort, with no complications.

An unusual occurrence of penetrating aortic arch injury by a ball-point pen: a case report and review of the literature.

BACKGROUND: Aortic arch injuries account for about 8% of thoracic aortic injuries. Penetrating zone I neck injuries account for 18% of vascular injuries in the neck and have great potential to traverse to involve thoracic vascular structures as well. The hard and soft signs of vascular injury facilitate triage of patients on an individual basis. We present a case of a ball-point pen traversing through zone I of the neck and causing penetrating aortic arch injury with minimal mediastinal haemorrhage. CASE PRESENTATION: We present a polytrauma patient who was admitted with traumatic brain injury and a ball-point pen lodged above the sternal notch in zone I of the neck following a road traffic accident. He underwent mediastinal exploration via a median sternotomy. The ball-point pen was found penetrating the anterior wall of the aortic arch and resting in its lumen. The ball-point pen was successfully explanted and primary repair of the penetrating aortic arch injury was done. He had an uneventful recovery without any added secondary neurological complications. CONCLUSION: Penetrating aortic arch injuries are rare compared to injuries of the ascending aorta and descending aorta. They require a high index of suspicion, rapid investigation and urgent intervention in view of their high associated fatality. The ball-point pen in this case assumed the shape of a plug which acted as a seal at the site of injury preventing catastrophic exsanguination.

Resuscitative endovascular balloon occlusion of the aorta in Canada: a context-specific position paper from the Canadian Collaborative for Urgent Care Surgery (CANUCS).

SummaryResuscitative endovascular balloon occlusion of the aorta (REBOA) is a well-described intervention for noncompressible torso hemorrhage. Several Canadian centres have included REBOA in their hemorrhagic shock protocols. However, REBOA has known complications and equipoise regarding its use persists. The Canadian Collaborative on Urgent Care Surgery (CANUCS) comprises surgeons who provide acute trauma care and leadership in Canada, with experience in REBOA implementation, use, education and research. Our goal is to provide evidence- and experience-based recommendations regarding institutional implementation of a REBOA program, including multidisciplinary educational programs, attention to device and care pathway logistics, and a robust quality assurance program. This will allow Canadian trauma centres to maximize patient benefits and minimize risks of this potentially life-saving technology.

Minimising the biases in the observational study of resuscitative endovascular balloon occlusion of the aorta: a research protocol for a prospective study analysed with propensity score matching with time-varying covariates.

INTRODUCTION: Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been used as a bridge to definitive bleeding control of subdiaphragmatic injury. Since previous observational studies have poorly adjusted for confounding factors, it is necessary to incorporate REBOA-specific and time-varying covariates in the model. We hypothesised that REBOA improves the survival of haemodynamically unstable torso trauma patients after comparing the REBOA group with a matched control group (non-REBOA group). METHODS AND ANALYSIS: The Japanese Association for the Surgery of Trauma-REBOA Study is a prospective, multicentre, matched cohort study organised by the Clinical Trial Committee of the Japanese Association for the Surgery of Trauma. To minimise observational study biases, this study will prospectively register traumatic shock patients who require bleeding control within 60 min upon arrival at the emergency department, with in-hospital mortality as the primary outcome. After the data set is fixed, the missing values for all variables will be imputed using the multiple imputation technique. In the primary analysis, propensity scores for the probability of REBOA decision (regardless of the actual REBOA deployment) will be calculated from the baseline information using a logistic regression generalised linear mixed-effects model, which will be performed for both the REBOA use and non-REBOA use groups. ETHICS AND DISSEMINATION: This study was approved by the ethics committee of each participating hospital. The results will be disseminated to the participating hospitals, submitted to peer-reviewed journals for publication and presented at congresses. TRIAL REGISTRATION NUMBER: UMIN Clinical Trials Registry (UMIN000035458).

REBOA Use, Practices, Characteristics, and Implementations Across Various US Trauma Centers.

BACKGROUND: Hemorrhage accounts for >30% of trauma-related mortalities. Use of resuscitative endovascular balloon occlusion of the aorta (REBOA) for temporary hemostasis in the civilian population remains controversial. We aim to investigate REBOA practices through analysis of surgeon and trauma center characteristics, implementation, patient characteristics, and overall opinions. METHODS: An anonymous 30-question standardized online survey on REBOA use was administered to active trauma surgeon members of the Eastern Association for the Surgery of Trauma. RESULTS: A total of 345 responses were received, and 130/345 (37.7%) reported REBOA being favorable, 42 (12.2%) reported REBOA unfavorably, and 173 (50.1%) were undecided. The majority of respondents (87.6%) reported REBOA performance in the trauma bay. 170 (49.3%) of respondents reported having deployed REBOA at least once over the past 2 years. 80.0% reported blunt trauma being the most common mechanism of injury in REBOA patients. Resuscitative endovascular balloon occlusion of the aorta deployment in zone 3 of the aorta was significantly higher in patients reported to suffer a pelvic fracture or pelvic hemorrhage, whereas REBOA deployment in zone 1 was significantly higher among patients reported to suffer hepatic, splenic, or other intra-abdominal hemorrhage (P < .05). CONCLUSION: Among survey respondents, frequency of REBOA use was low along with knowledge of clear indications for use. While current REBOA usage among respondents appeared to model current guidelines, additional research regarding REBOA indications, ideal patient populations, and outcomes is needed in order to improve REBOA perception in trauma surgeons and increase frequency of use.

Gastroesophageal resuscitative occlusion of the aorta prolongs survival in a lethal liver laceration model.

BACKGROUND: Noncompressible torso hemorrhage management remains a challenge especially in the prehospital setting. We evaluated a device designed to occlude the aorta from the stomach (gastroesophageal resuscitative occlusion of the aorta [GROA]) for its ability to stop hemorrhage and improve survival in a swine model of lethal liver laceration and compared its performance to resuscitative endovascular balloon occlusion of the aorta (REBOA) and controls. METHODS: Swine (n = 24) were surgically instrumented and a 30% controlled arterial hemorrhage over 20 minutes was followed by liver laceration. Animals received either GROA, REBOA, or control (no treatment) for 60 minutes. Following intervention, devices were deactivated, and animals received whole blood and crystalloid resuscitation. Animals were monitored for an additional 4 hours. RESULTS: The liver laceration resulted in the onset of class IV shock. Mean arterial blood pressure (MAP) (standard deviation) decreased from 84.5 mm Hg (11.69 mm Hg) to 27.1 mm Hg (5.65 mm Hg) at the start of the intervention. Seven of eight control animals died from injury prior to the end of the intervention period with a median survival (interquartile) time of 10.5 minutes (12 minutes). All GROA and REBOA animals survived the duration of the intervention period (60 minutes) with median survival times of 86 minutes (232 minutes) and 79 minutes (199 minutes) after resuscitation, respectively. The GROA and REBOA animals experienced a significant improvement in survival compared with controls (p = 0.01). Resuscitative endovascular balloon occlusion of the aorta resulted in higher MAP at the end of intervention 114.6 mm Hg (22.9 mm Hg) compared with GROA 88.2 mm Hg (18.72 mm Hg) (p = 0.024), as well as increased lactate compared with GROA 13.2 meq·L-1 (1.56 meq·L-1) versus 10.5 meq·L-1 (1.89 meq·L-1) (p = 0.028). Histological examination of the gastric mucosa in surviving animals revealed mild ischemic injury from both GROA and REBOA. CONCLUSION: The GROA and REBOA devices were both effective at temporarily stanching lethal noncompressible torso hemorrhage of the abdomen and prolonging survival.

Resuscitative endovascular balloon occlusion of the aorta: simulation improves performance but may require interval training to prevent skill degradation.

PURPOSE: Surgical trainees are exposed to less procedures with increasing need for simulation. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has become increasingly implemented for hemorrhage control, yet most courses are catered to faculty level with little data on trainees. We propose that routine training in this critical procedure will improve trainee performance over time. METHODS: This is a prospective, observational study at a level I trauma center involving a monthly trauma procedural program. Early in the month, trainees received hands-on REBOA training; at the end, trainees underwent standardized, class-based evaluation on a perfused trainer. Score percentages were recorded (0-100%). Endpoints included early, mid and late performance (2-12 months). Paired T-test and Pearson's coefficient were used to evaluate differences and strength of association between time between training and performance. RESULTS: 25 trainees participated with 5 and 11 repeat learners in the PGY-2 and PGY-3 classes, respectively. Median early performance score was 62.5% (IQR 56-81) for PGY-2s and 91.6% (IQR 75-100) in PGY-3s. Pearson's coefficient between time between and training and score demonstrated a weak correlation in the PGY-2s (r2 = - 0.13), but was more pronounced in the PGY-3s (r2 = - 0.44) with an inflection point at 5 months. CONCLUSIONS: Routine REBOA training in trainees is associated with improvement in performance within a short period of time. Skill degradation was most pronounced in trainees who did not receive training for more than 5 months. Trainees can be successfully trained in REBOA; however, this should be done at shorter intervals to prevent skill degradation.

Resuscitative Endovascular Balloon Occlusion of Aorta: A Systematic Review.

BACKGROUND: The data on resuscitative endovascular balloon occlusion of the aorta (REBOA) use continue to grow with its increasing use in trauma centers. The data in her last 5 years have not been systematically reviewed. We aim to assess current literature related to REBOA use and outcomes among civilian trauma populations. METHODS: A literature search using PubMed, EMBASE, and JAMA Network for studies regarding REBOA usage in civilian trauma from 2016 to 2020 is carried out. This review followed preferred reporting items for systematic reviews and meta-analysis guidelines. RESULTS: Our search yielded 35 studies for inclusion in our systematic review, involving 4073 patients. The most common indication for REBOA was patient presentation in hemorrhagic shock secondary to traumatic injury. REBOA was associated with significant systolic blood pressure improvement. Of 4 studies comparing REBOA to non-REBOA controls, 2 found significant mortality benefit with REBOA. Significant mortality improvement with REBOA compared to open aortic occlusion was seen in 4 studies. In the few studies investigating zone placement, highest survival rate was seen in patients undergoing zone 3. Overall, reports of complications directly related to overall REBOA use were relatively low. CONCLUSION: REBOA has been shown to be effective in promoting hemodynamic stability in civilian trauma. Mortality data on REBOA use are conflicting, but most studies investigating REBOA vs. open occlusion methods suggest a significant survival advantage. Recent data on the REBOA technique (zone placement and partial REBOA) are sparse and currently insufficient to determine advantage with any particular variation. Overall, larger prospective civilian trauma studies are needed to better understand the benefits of REBOA in high-mortality civilian trauma populations. STUDY TYPE: Systematic Review. LEVEL OF EVIDENCE: III- Therapeutic.