Temporal Changes in REBOA Utilization Practices are Associated With Increased Survival: an Analysis of the AORTA Registry

A PROMPT Update on Partial REBOA: Initial Clinical Data and Overview of the DoD-Funded Partial REBOA Outcomes Multicenter ProspecTive (PROMPT) Study

INTRODUCTION

Retrograde Endovascular Balloon Occlusion of the Aorta (REBOA) is an effective management for the transient responder, but the ischemic consequences of complete aortic occlusion currently limit its use. Multiple DoD-funded preclinical studies have clearly demonstrated that partial REBOA reduces distal ischemia to potentially extend safe occlusion times, while still providing effective temporization of noncompressible torso hemorrhage. Early versions of REBOA devices were designed to completely occlude the aorta and had little ability to provide partial occlusion. Recently, a new REBOA device (pREBOA-PRO) was designed specifically to allow for partial occlusion, with the hypothesis that this may reduce the complications of aortic occlusion and extend safe occlusion times while maintaining the benefits on cardiac and cerebrovascular circulation as well as reductions in resuscitation requirements.

MATERIALS AND METHODS

To ascertain the impact of a new purpose-built partial REBOA device on the extension of safe occlusion time, the Partial REBOA Outcomes Multicenter ProspecTive (PROMPT) trial compared available data from the pREBOA-PRO with existing data from 200 clinical uses of pREBOA-PRO and available data in the AAST AORTA Registry were reviewed to design primary endpoints and clinical evidence for a prospective multi-center trial, the PROMPT Study. Together with the endpoints identified in preclinical studies of partial REBOA, primary endpoints for the PROMPT study were identified and power analyses were conducted to determine the target patient enrollment goals.

RESULTS

Results from the clinical implementation of partial REBOA at a single trauma center were used to conduct the initial power analysis for the primary endpoint of Acute Kidney Injury (AKI) after prolonged occlusion. The rate of AKI after complete REBOA was 55% (12/20) compared to 33% (4/12) after partial REBOA (Madurska et al., 2021). With an alpha of 0.05 and power (β) of 0.8, the projected sample size for comparison on a dichotomous outcome is 85 patients for the assessment of AKI. Initial power and endpoint analyses have been confirmed and extended with the ongoing analysis of partial and complete REBOA reported in the AORTA database. These analyses confirm preclinical findings which show that compared to complete REBOA, partial REBOA is associated with extended occlusion time in zone 1 (complete: 31 min vs. partial: 45 min, P = 0.003), lower rates of AKI after zone 1 occlusion (complete: 33% vs. partial: 19%, P = 0.05) and reduced resuscitation requirements (e.g., 25% reduction in pRBC administration: complete: 18 units vs. partial: 13 units, P = 0.02).

CONCLUSIONS

The DoD-funded PROMPT study of partial REBOA will provide prospective observational clinical data on patients being treated with pREBOA-PRO. Outcomes will be stratified based on partial or complete occlusion to address whether partial REBOA has additional clinical benefits over complete REBOA, such as decreased distal ischemia, extension of safe occlusion time, improved hemodynamics during transition to and from occlusion, and reduced interoperative bleeding and blood product use. The results from this study are expected to confirm previous data demonstrating reduction of ischemic sequalae, improved transition to reperfusion, and reduced resuscitative requirements compared to complete REBOA.

Vascular complications secondary to resuscitative endovascular balloon occlusion of the aorta placement at a Level 1 Trauma Center

OBJECTIVE

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is designed to manage severe hemorrhagic shock. Popularized in medical care during military conflicts, the concept has emerged as a lifesaving technique that is utilized around the United States. Literature on risks of REBOA placement, especially vascular injuries, are not well-reported. Our goal was to assess the incidence of vascular injury from REBOA placement and the risk factors associated with injury and death among these patients at our institution.

METHODS

We performed a retrospective cohort study of all patients who underwent REBOA placement between September 2017 and June 2022 at our Level 1 Trauma Center. The primary outcome variable was the presence of an injury related to REBOA insertion or use. Secondary outcomes studied were limb loss, the need for dialysis, and mortality. Data were analyzed using descriptive statistics, χ2, and t-tests as appropriate for the variable type.

RESULTS

We identified 99 patients who underwent REBOA placement during the study period. The mean age of patients was 43.1 ± 17.2 years, and 67.7% (67/99) were males. The majority of injuries were from blunt trauma (79.8%; 79/99). Twelve of the patients (12.1%; 12/99) had a vascular injury related to REBOA placement. All but one required intervention. The complications included local vessel injury (58.3%; 7/12), distal embolization (16.7%; 2/12), excessive bleeding requiring vascular consult (8.3%; 1/12), pseudoaneurysm requiring intervention (8.3%; 1/12), and one incident of inability to remove the REBOA device (8.3%; 1/12). The repairs were performed by vascular surgery (75%; 9/12), interventional radiology (16.7%; 2/12), and trauma surgery (8.3%; 1/12). There was no association of age, gender, race, and blunt vs penetrating injury to REBOA-related complications. Mortality in this patient population was high (40.4%), but there was no association with REBOA-related complications. Ipsilateral limb loss occurred in two patients with REBOA-related injuries, but both were due to their injuries and not to REBOA-related ischemia.

CONCLUSIONS

Although vascular complications are not unusual in REBOA placement, there does not appear to be an association with limb loss, dialysis, or mortality if they are addressed promptly. Close coordination between vascular surgeons and trauma surgeons is essential in patients undergoing REBOA placement.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) in the presence of associated severe traumatic brain injury: A propensity-score matched study

BACKGROUND

Experimental work suggested that resuscitative Endovascular Balloon Occlusion of the aorta (REBOA) preserves cerebral circulation in animal models of traumatic brain injury. No clinical work has evaluated the role of REBOA in the presence of associated severe traumatic brain injury (TBI). We investigated the impacts of REBOA on neurological and survival outcomes.

METHODS

Propensity-score matched study, using the American College of Surgeons Trauma Quality Improvement Program database. Patients with severe TBI patients (Abbreviated Injury Scale ≥3) receiving REBOA within 4 ​h from arrival were matched with similar patients not receiving REBOA. Neurological matching included head AIS, pupils, and midline shift. Clinical outcomes were compared between the two groups.

RESULTS

434 REBOA patients were matched with 859 patients without REBOA. Patients in the REBOA group had higher rates of in-hospital mortality (63.6 ​% vs 44.2 ​%, p ​< ​0.001), severe sepsis (4.4 ​% vs 2.2 ​%, p ​= ​0.029), acute kidney injury (10.1 ​% vs 6.6 ​%, p ​= ​0.029), and withdrawal of life support (25.4 ​% vs 19.6 ​%, p ​= ​0.020) despite of lower craniectomy/craniotomy rate (7.1 ​% vs 12.7 ​%, p ​< ​0.002).

CONCLUSION

In patients with severe TBI, REBOA use is associated with an increased risk of in-hospital mortality, AKI, and infectious complications.

Consensus on resuscitative endovascular balloon occlusion of the aorta in civilian (prehospital) trauma care: A Delphi study

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) could prevent lethal exsanguination and support cardiopulmonary resuscitation. In prehospital trauma and medical emergency settings, a small population with high mortality rates could potentially benefit from early REBOA deployment. However, its use in these situations remains highly disputed. Since publication of the first Delphi study on REBOA, in which consensus was not reached on all addressed topics, new literature has emerged. The aim of this study was to establish consensus on the use and implementation of REBOA in civilian prehospital settings for noncompressible truncal hemorrhage and out-of-hospital cardiac arrest as well as for various in-hospital settings.

METHODS

A Delphi study consisting of three rounds of questionnaires was conducted based on a review of recent literature. REBOA experts with different medical specialties, backgrounds, and work environments were invited for the international panel. Consensus was reached when a minimum of 75% of panelists responded to a question and at least 75% (positive) or less than 25% (negative) of these respondents agreed on the questioned subject.

RESULTS

Panel members reached consensus on potential (contra)indications, physiological thresholds for patient selection, the use of ultrasound and practical, and technical aspects for early femoral artery access and prehospital REBOA.

CONCLUSION

The international expert panel agreed that REBOA can be used in civilian prehospital settings for temporary control of noncompressible truncal hemorrhage, provided that personnel are properly trained and protocols are established. For prehospital REBOA and early femoral artery access, consensus was reached on (contra)indications, physiological thresholds and practical aspects. The panel recommends the initiation of a randomized clinical trial investigating the use of prehospital REBOA for noncompressible truncal hemorrhage.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level V.

Computed tomography scanning is feasible in select patients with REBOA catheter deployment

BACKGROUND

Rapidly localizing and controlling bleeding is central to treating hemorrhagic shock. While REBOA allows temporary control, identifying the source of bleeding remains challenging. CT imaging with REBOA in place may provide information to direct hemorrhage control. The purpose of this study is to provide a descriptive summary of data comparing patients who did and did not undergo CT scan following REBOA deployment. Our hypothesis was that performing CT scan after REBOA placement in select patients is safe and can guide management of hemorrhagic shock.

METHODS

We queried the AAST AORTA registry for patients receiving REBOA at our level 1 trauma center from May 2017 to December 2021. Clinical data was obtained through the Trauma Registry of the American College of Surgeons (TRACS). Comparison groups were those who underwent CT scan after REBOA deployment versus those who did not undergo CT scan after REBOA deployment. The primary outcome was inhospital mortality, and secondary outcomes included hospital-, ICU-, and ventilator-free days.

RESULTS

61 patients underwent CT scan with REBOA in place; 25 patients proceeded directly to hemorrhage control. Patients with REBOA prior to CT were more likely to have blunt mechanism, higher ISS, pelvic bleeding, and zone 3 REBOA placement. Mortality was not significantly different (51 % vs. 64 %). Patients who underwent CT with REBOA were more likely to undergo hemorrhage control in interventional radiology (43 % vs. 0 %). There was no difference in hospital-, ICU-, and ventilator-free days.

DISCUSSION

We demonstrate the feasibility of performing CT in select trauma patients who undergo REBOA. We describe a pathway to enable expeditious workup and management of these patients. Optimal hemorrhage control management is impacted by CT scans when it can be performed. It is important to note that this is a severely injured patient population, and mortality is high even when hemorrhage is controlled.

LEVEL OF EVIDENCE

III.

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.

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.

Efficacy of partial and complete resuscitative endovascular balloon occlusion of the aorta in the hemorrhagic shock model of liver injury

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) can temporarily control traumatic bleeding. However, its prolonged use potentially leads to ischemia-reperfusion injury (IRI). Partial REBOA (pREBOA) can alleviate ischemic burden; however, its security and effectiveness prior to operative hemorrhage control remains unknown. Hence, we aimed to estimate the efficacy of pREBOA in a swine model of liver injury using an experimental sliding-chamber ballistic gun.

METHODS

Twenty Landrace pigs were randomized into control (no aortic occlusion) (n=5), intervention with complete REBOA (cREBOA) (n=5), continuous pREBOA (C-pREBOA) (n=5), and sequential pREBOA (S-pREBOA) (n=5) groups. In the cREBOA and C-pREBOA groups, the balloon was inflated for 60 min. The hemodynamic and laboratory values were compared at various observation time points. Tissue samples immediately after animal euthanasia from the myocardium, liver, kidneys, and duodenum were collected for histological assessment using hematoxylin and eosin staining.

RESULTS

Compared with the control group, the survival rate of the REBOA groups was prominently improved (all P<0.05). The total volume of blood loss was markedly lower in the cREBOA group (493.14±127.31 mL) compared with other groups (P<0.01). The pH was significantly lower at 180 min in the cREBOA and S-pREBOA groups (P<0.05). At 120 min, the S-pREBOA group showed higher alanine aminotransferase (P<0.05) but lower blood urea nitrogen compared with the cREBOA group (P<0.05).

CONCLUSION

In this trauma model with liver injury, a 60-minute pREBOA resulted in improved survival rate and was effective in maintaining reliable aortic pressure, despite persistent hemorrhage. Extended tolerance time for aortic occlusion in Zone I for non-compressible torso hemorrhage was feasible with both continuous partial and sequential partial measures, and the significant improvement in the severity of acidosis and distal organ injury was observed in the sequential pREBOA.

Revisiting the promise, practice and progress of resuscitative endovascular balloon occlusion of the aorta

PURPOSE OF REVIEW

The use of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) to temporarily control bleeding and improve central perfusion in critically injured trauma patients remains a controversial topic. In the last decade, select trauma services around the world have gained experience with REBOA. We discuss the recent observational data together with the initial results of the first randomized control trial and provide a view on the next steps for REBOA in trauma resuscitation.

RECENT FINDINGS

While the observational data continue to be conflicting, the first randomized control trial signals that in the UK, in-hospital REBOA is associated with harm. Likely a result of delays to haemorrhage control, views are again split on whether to abandon complex interventions in bleeding trauma patients and to only prioritize transfer to the operating room or to push REBOA earlier into the post injury phase, recognizing that some patients will not survive without intervention.

SUMMARY

Better understanding of cardiac shock physiology provides a new lens in which to evaluate REBOA through. Patient selection remains a huge challenge. Invasive blood pressure monitoring, combined with machine learning aided decision support may assist clinicians and their patients in the future. The use of REBOA should not delay definitive haemorrhage control in those patients without impending cardiac arrest.

The Implementation of a Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) Program at a Level 1 New England Trauma Center: Feasibility and Early Outcomes

OBJECTIVES

We evaluated the feasibility of implementing a Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) program at our urban level 1 trauma center and evaluated early outcomes.

DESIGN

A multidisciplinary committee including physicians (trauma surgery, emergency medicine, vascular surgery, and interventional radiology) and nurses created clinical practice guidelines for the placement of REBOA at our institution. All trauma surgeons and critical care board certified emergency medicine physicians were trained in placement and nurses received management training. A formal review process was implemented to identify areas for improvement. Finally, we instituted refresher training to maintain REBOA competency. Trauma patients with noncompressible torso hemorrhage from blunt or penetrating injuries who were partial or nonresponders to blood product resuscitation were included. Pregnant patients, children, or patients with significant hemothorax or suspected aortic or cardiac injury were excluded.

RESULTS

Over seven months, eight catheters were successfully placed, all on the first attempt, including six in Zone 3 and two in Zone 1. All Zone 3 catheters were placed for pelvic fracture-related bleeding which were subsequently embolized. The Zone 1 catheters were placed immediately preoperatively for intraabdominal bleeding. Upon committee review, one critique was made regarding zone selection. One patient developed an arteriovenous fistula after placement which resolved without intervention. There were no other complications and all patients survived to discharge.

CONCLUSIONS

An REBOA program is feasible and safe following a comprehensive multidisciplinary effort. The efforts described here can be utilized by similar trauma programs for adaptation of this endovascular approach to bleeding control.

The undisclosed disclosures: The dollar-outcome relationship in resuscitative endovascular balloon occlusion of the aorta

BACKGROUND

Despite its rapid evolution, resuscitative endovascular balloon occlusion of the aorta (REBOA) remains a controversial intervention that continues to generate active research. Proper conflict of interest (COI) disclosure helps to ensure that research is conducted objectively, without bias. We aimed to identify the accuracy of COI disclosures in REBOA research.

METHODS

Literature search was performed using the keyword "REBOA" on PubMed. Studies on REBOA with at least one American author published between 2017 and 2022 were identified. The Centers for Medicare and Medicaid Services Open Payments database was used to extract information regarding payments to the authors from the industry. This was compared with the COI section reported in the manuscripts. Conflict of interest disclosure was defined as inaccurate if the authors failed to disclose any amount of money received from the industry. Descriptive statistics were performed.

RESULTS

We reviewed a total of 524 articles, of which 288 articles met the inclusion criteria. At least one author received payments in 57% (165) of the articles. Overall, 59 authors had a history of payment from the industry. Conflict of interest disclosure was inaccurate in 88% (145) of the articles where the authors received payment.

CONCLUSION

Conflict of interest reports are highly inaccurate in REBOA studies. There needs to be standardization of reporting of conflicts of interest to avoid potential bias.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level IV.

Defence Medical Services' REBOA training course

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) enables temporary haemorrhage control and physiological stabilisation. This article describes the bespoke Defence Medical Services (DMS) training package for effectively using REBOA. The article covers how the course was designed, how the key learning objectives are taught, participant feedback and the authors' perceptions of future training challenges and opportunities. Since the inaugural training course in April 2019, the authors have delivered six courses, training over 100 clinicians. For the first time in the UK DMS, we designed and delivered a robust specialist endovascular training programme, with demonstrable, significant increases in confidence and competence. As a result of this course, the first DMS REBOA-equipped forward surgical teams deployed in June 2019. Looking to the future, there is a requirement to develop an assessment of skill retention and the potential need for revalidation.

Use of Tranexamic Acid With Resuscitative Endovascular Balloon Occlusion of the Aorta is Associated With Higher Distal Embolism Rates: Results From the American Association of Surgery for Trauma Aortic Occlusion and Resuscitation for Trauma and Acute Care Surgery Trial

INTRODUCTION

Tranexamic acid (TXA) use has been associated with thrombotic complications.

OBJECTIVE

We aim to investigate outcomes associated with TXA use in the setting of high- (HP) and low-profile (LP) introducer sheaths for resuscitative endovascular balloon occlusion of the aorta (REBOA).

PARTICIPANTS

The Aortic Occlusion and Resuscitation for Trauma and Acute Care Surgery (AORTA) database was queried for patients who underwent REBOA using a low-profile 7 French (LP) or high-profile, 11-14 French (HP) introducer sheaths between 2013 and 2022. Demographics, physiology, and outcomes were examined for patients who survived beyond the index operation.

RESULTS

574 patients underwent REBOA (503 LP, 71 HP); 77% were male, mean age was 44 ± 19 and mean injury severity score (ISS) was 35 ± 16. 212 patients received TXA (181 [36%] LP, 31 [43.7%] HP). There were no significant differences in admission vital signs, GCS, age, ISS, SBP at AO, CPR at AO, and duration of AO among LP and HP patients. Overall, mortality was significantly higher in the HP (67.6%) vs the LP group (54.9%; P = .043). Distal embolism was significantly higher in the HP group (20.4%) vs the LP group (3.9%; P < .001). Logistic regression demonstrated that TXA use was associated with a higher rate of distal embolism in both groups (OR = 2.92; P = .021). 2 LP patients (one who received TXA) required an amputation.

CONCLUSION

Patients who undergo REBOA are profoundly injured and physiologically devastated. Tranexamic acid was associated with a higher rate of distal embolism in those who received REBOA, regardless of access sheath size. For patients receiving TXA, REBOA placement should be accompanied by strict protocols for immediate diagnosis and treatment of thrombotic complications.

MILD THERAPEUTIC HYPOTHERMIA REDUCES ISCHEMIA-REPERFUSION INJURY AFTER ZONE 1 REBOA IN A SWINE HEMORRHAGIC SHOCK MODEL

ABSTRACT

Background: Resuscitative balloon occlusion of the aorta (REBOA) is an endovascular hemostasis method used for the management of traumatic abdominal and pelvic hemorrhages. However, REBOA-associated ischemia-reperfusion injury complication limits its blocking time. We hypothesized that mild therapeutic hypothermia would relieve ischemia-reperfusion injury caused by prolonged zone 1 REBOA. Methods: Ten pigs were anesthetized, intubated, and subsequently struck with the experimental sliding-chamber ballistic gun to inflict liver damage. Animals were randomized to hypothermia (60 min of zone 1 REBOA with external cooling for 180 min, n = 5) or control (60 min of zone 1 REBOA with no external cooling, n = 5). Physiological and laboratory parameters were monitored and assessed. Distal organs were obtained for histologic analysis. Results: At 180 min, compared with the control, the hypothermia animals exhibited significantly increased pH and significantly reduced lactate, hemoglobin, and hematocrit (all P < 0.05). The change of lactate from 0 to 180 min in hypothermia animals was less than that in the control ( P = 0.02). The total bleeding in the control group was significantly less than the hypothermia ( P < 0.01). In the hypothermia group, prothrombin time at 120 and 180 min was significantly longer than that at baseline (all P < 0.05). Compared with the control, animals in the hypothermia group showed slighter pathological injury of the distal organs and significantly lower overall injury score (all P < 0.05). Conclusions: Mild therapeutic hypothermia during prolonged zone 1 REBOA offered extraordinary distal organ preservation and decreased metabolic acidosis.

Editor's Choice - Systematic Review and Meta-Analysis of Lower Extremity Vascular Complications after Arterial Access for Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA): An Inevitable Concern?

OBJECTIVE

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is used to temporise non-compressible torso haemorrhage. Recent data have suggested that vascular access complications secondary to REBOA placement are higher than initially anticipated. This updated systematic review and meta-analysis aimed to determine the pooled incidence rate of lower extremity arterial complications after REBOA.

DATA SOURCES

PubMed, Scopus, Embase, conference abstract listings, and clinical trial registries.

REVIEW METHODS

Studies including more than five adults undergoing emergency REBOA for exsanguinating haemorrhage that reported access site complications were eligible for inclusion. A pooled meta-analysis of vascular complications was performed using the DerSimonian-Laird weights for the random effects model, presented as a Forest plot. Further meta-analyses compared the relative risk of access complications between different sheath sizes, percutaneous access techniques, and indications for REBOA. Risk of bias was assessed using the Methodological Index for Non-Randomised Studies (MINORS) tool.

RESULTS

No randomised controlled trials were identified, and the overall study quality was poor. Twenty-eight studies including 887 adults were identified. REBOA was performed for trauma in 713 cases. The pooled proportion rate of vascular access complications was 8.6% (95% confidence interval 4.97 - 12.97), with substantial heterogeneity (I2 = 67.6%). There was no significant difference in the relative risk of access complications between 7 and > 10 F sheaths (p = .54), or between ultrasound guided and landmark guided access (p = .081). However, traumatic haemorrhage was associated with a significantly higher risk of complications compared with non-traumatic haemorrhage (p = .034).

CONCLUSION

This updated meta-analysis aimed to be as comprehensive as possible considering the poor quality of source data and high risk of bias. It suggested that lower extremity vascular complications were higher than originally suspected after REBOA. While the technical aspects did not appear to impact the safety profile, a cautious association could be drawn between REBOA use for traumatic haemorrhage and a higher risk of arterial complications.

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.

Resuscitative Endovascular Balloon Occlusion of the Aorta is Associated with Increased Risk of Extremity Compartment Syndrome

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been used as a temporizing procedure to control intra-abdominal or pelvic bleeding. Theoretically, occlusion of the aorta and the resulting ischemia-reperfusion of the lower extremities may increase the risk of extremity compartment syndrome (CS). To date, no study has addressed systematically the incidence and risk factors of CS following REBOA intervention. The purpose of this study was to address this knowledge gap.

METHODS

Adult trauma patients from the American College of Surgeons Trauma Quality Improvement Program (ACS-TQIP) database (2016-2019) were included. Patients who received REBOA within 4 h of admission were compared to patients without REBOA after propensity score matching for demographics, vital signs on admission, comorbidities, injury severity of different body regions, pelvic and lower extremity fractures, vascular trauma to the lower extremities, fixation for fractures, angioembolization (AE) for pelvis, preperitoneal pelvic packing (PPP), laparotomy, and venous thromboembolism (VTE) prophylaxis. The primary outcomes were rates of lower extremity CS and fasciotomy and acute kidney injury (AKI). Secondary outcomes included mortality.

RESULTS

There were 534 patients who received REBOA matched with 1043 patients without REBOA. Overall, patients in the REBOA group had significantly higher rates of CS than no REBOA patients [5.4% vs 1.1%, p < 0.001, OR: 5.39]. The risk of CS remained significantly higher in the subgroups of patients with or without pelvic or lower extremity fractures, as well as in the subgroup of patients with associated extremity vascular injury [11.2% vs 1.5%, p < 0.001, OR: 8.12].The fasciotomy and AKI rates were significantly higher in the REBOA group (5.8% vs 1.2%, p < 0.001 and 12.9% vs 7.4%, p< 0.001 respectively).

CONCLUSION

REBOA use is associated with a higher risk of lower extremity CS, fasciotomy and AKI, especially in patients with associated lower extremity vascular injuries. These complications should be taken into account when considering REBOA use, and close observation for this complication should always be part of the routine monitoring.

REBOA: Expanding Applications From Traumatic Hemorrhage to Obstetrics and Cardiopulmonary Resuscitation, From the AJR Special Series on Emergency Radiology

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has emerged over the past decade as a technique to control life-threatening hemorrhage and treat hemorrhagic shock, being increasingly used to treat noncompressible traumatic torso hemorrhage. Reports during this time also support the use of a REBOA device for an expanding range of indications including nontraumatic abdominal hemorrhage, postpartum hemorrhage, placenta accreta spectrum (PAS) disorder, and cardiopulmonary resuscitation (CPR). The strongest available evidence supports REBOA as a lifesaving adjunct to definitive surgical management in trauma and as a method to help avoid hysterectomy in select patients with postpartum hemorrhage or PAS disorder. In comparison with initial descriptions of complete REBOA inflation, techniques for partial REBOA inflation have been introduced to achieve hemodynamic stability while minimizing adverse events relating to reperfusion injuries. Fluoroscopy-free REBOA has been described in various settings, including trauma, obstetrics, and out-of-hospital cardiac arrest. As the use of REBOA expands outside the trauma setting and into nontraumatic abdominal hemorrhage, obstetrics, and CPR, it is imperative for radiologists to become familiar with this technology, its proper placement, and its potential adverse sequelae.

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.

When REBOA grows wings: Resuscitative endovascular balloon occlusion of the aorta to facilitate aeromedical transport

Background

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a helpful adjunct in the control of non-compressible truncal hemorrhage. Concerns regarding ischemia time limits its applicability in transfer. We describe the first reported case of civilian transfer via aeromedical transport to a higher level of care with a zone 3 REBOA catheter deployed.

Case report

We present the case of a patient in hemorrhagic shock with a complex pelvic fracture exceeding the capability of a rural level-two trauma center requiring the use of REBOA catheter to permit aeromedical transport to a level-one trauma center for definitive embolization.

Conclusion

Deployment of REBOA catheter to facilitate aeromedical transport to an appropriate level of care may be considered if travel times can be kept brief and there is a process and training in place to empower flight medics to consider transporting with a REBOA deployed.

Predicting success of resuscitative endovascular occlusion of the aorta: Timing supersedes variable techniques in predicting patient survival

BACKGROUND

Resuscitative endovascular occlusion of the aorta (REBOA) is used for temporary aortic occlusion of trauma patients in the management of noncompressible hemorrhage. Previous studies have focused on how to properly perform REBOA in the trauma environment to improve survival rates, but high-grade evidence defining the ideal patient population does not yet exist. This post hoc analysis of the Emergent Truncal Hemorrhage Control Study seeks to identify the most important clinical factors for physicians to consider when selecting for REBOA candidates and their potential survival following REBOA.

METHODS

Post hoc analysis of a large, multicenter, prospective observational study conducted at six level 1 trauma centers, 2017 to 2018, was performed. An onsite data collector documented all time points for REBOA patients since admission. Candidate predictors were demographics; injury severity; physiology preprocedure, during procedure, and postprocedure; cardiopulmonary resuscitation; and REBOA-specific variables (time to procedure, procedure-related time intervals, access site, technique, sheath size, catheter length, balloon volume, deployment zone). Predictive models for survival at three different time points along the trauma triage and REBOA process timeline ("Admission," "REBOA Initiation," and "Postaortic Occlusion") were devised by logistic regression.

RESULTS

Eighty-eight patients had REBOA placement. The Admission model selected age, Glasgow Coma Scale, and admission systolic blood pressure as significant predictors of survival (area under the receiver operating characteristic curve [AUROC], 0.86; 95% CI, 0.77-0.94). The REBOA Initiation and Postaortic Occlusion models selected age, Glasgow Coma Scale, and the systolic blood pressure measured just before balloon inflation as predictors for survival (AUROC, 0.87 [95% CI, 0.78-0.97] and AUROC, 0.90 [95% CI, 0.81-0.99], respectively). No REBOA procedural variables were identified as predictors of patient survival.

CONCLUSION

Only patient-specific criteria of age, neurologic status, and severity of shock predicted survival. The hemodynamic stability of the patient at the time REBOA is initiated is more important than how REBOA is initiated. These findings suggest that earlier preparation for REBOA placement may be a key to improved survival.

LEVEL OF EVIDENCE

Therapeutic, level IV.