Training and assessment of competence in resuscitative endovascular balloon occlusion of the aorta (REBOA) - a systematic review

Has the balloon really burst? Analysis of "the UK-REBOA randomized clinical trial"

BACKGROUND

Uncontrolled hemorrhagic shock is a leading cause of early death after injury. Resuscitative endovascular balloon occlusion of the aorta (REBOA) represents a paradigm shift in achieving hemodynamic stability and its implementation still remain controversial in different settings. The recently published UK-REBOA Randomized Clinical Trial aimed to determine the effectiveness of REBOA in patients with hemorrhagic shock, concluding its increased mortality compared with standard care alone.

METHODS

An adjustment of the statistical analysis was performed and a comprehensive analysis was proposed to address the study's limitations and demonstrate that these conclusions cannot be considered as benchmarks.

RESULTS

Primary and secondary outcomes were analyzed using Bayesian logistic regression and generalized linear models suitable for the outcome distribution. No statistically significant differences were observed between the two groups for the primary outcome (p-value 0.3341) nor in most of the secondary outcomes. The results of the principal stratum analyses (to account for intercurrent events) also did not show significant differences after the statistical analysis tests.

CONCLUSION

It cannot be stated that REBOA increases mortality compared with standard care alone in trauma patients with exsanguinating hemorrhage. Further studies and adequate simulation training programs in REBOA are critical to its successful implementation within a trauma system and to identify the optimum settings and patients.

A Novel REBOA Training Curriculum for Emergency Medicine Residents: A Pilot Study

BACKGROUND

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) is a potentially life-saving intervention to treat noncompressible torso hemorrhage. Traditionally, REBOA use has been limited to surgeons. However, emergency physicians are often the first point-of-contact and are well-versed in obtaining rapid vascular access and damage control resuscitation, making them ideal candidates for REBOA training.

STUDY OBJECTIVES

To fill this gap, we designed and evaluated a REBOA training curriculum for emergency medicine (EM) residents.

METHODS

Participants enrolled in an accredited 4-year EM residency program (N = 11) completed a 12-hour REBOA training course. Day 1 included lectures, case studies, and hands-on training using REBOA task trainers and perfused cadavers. Day 2 included additional practice and competency evaluations. Assessments included a 25-item written knowledge exam, decision-making on case studies, REBOA placement success, and time-to-placement. Participants returned at 4 months to assess long-term retention. Data were analyzed using t-tests and nonparametric statistics at p < 0.05.

RESULTS

Scores on a 25-item multiple choice test significantly increased from pre-training (65% ± 5%) to post-training (92% ± 1%), p < 0.001. On Day 2, participants scored 100% on correct recognition of REBOA indications and scored 100% on correct physical placement of REBOA. Exit surveys indicated increased preparedness, confidence, and support for incorporating this course into EM training. Most importantly, REBOA knowledge, correct recognition of REBOA indications, and correct REBOA placement skills were retained by the majority of participants at 4 months.

CONCLUSION

This course effectively teaches EM residents the requisite skills for REBOA competence and proper placement. This study could be replicated at other facilities with larger, more diverse samples, aiming to expand the use of REBOA in emergency physicians and reducing preventable deaths in trauma.

[Medical extended reality in digital emergency medicine : From education to clinical application]

BACKGROUND

Emergency medicine faces the challenge of providing optimal care with limited resources. Especially in rare but critical situations (high-acuity low occurrence [HALO] situations), sound expertise is essential. Previous training approaches are time-limited and resource-intensive.

AIM OF THE WORK

Medical extended reality (MXR) offers promising solutions. This article gives insight into the different areas of MXR and shows the application of MXR in emergency medicine using the HALO-MXR concept as an example.

RESULTS AND DISCUSSION

MXR encompasses augmented reality (AR), virtual reality (VR) and mixed reality (MR). AR overlays digital information on the real world, enhancing perception and enabling interactive elements. VR creates an artificial three-dimensional (3D) environment in which the user is immersed. MR combines real and virtual elements. MXR offers advantages such as location-independent learning, virtual mentoring and scalability. However, it cannot replace existing training formats, but should be embedded in an overall concept. The HALO-MXR concept at Inselspital Bern includes e‑learning, simulation-based training in VR and on-site, and HALO-Assist support through augmented reality. HALO-Assist provides around-the-clock AR support for HALO procedures via audio and video communication as well as overlayed annotations, objects and flowcharts.

CONCLUSION

The integration of MXR into emergency medicine promises more efficient use of resources and enhanced training opportunities. The HALO-MXR concept demonstrates how MXR effectively combines simulation-based training in VR and AR assist to enhance the application of HALO procedures.

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.

[Effect of a 1-day "REBOA course" on the theoretical and practical skills for the prehospital REBOA setting : Experiences from the RIBCAP-HEMS project]

Resuscitative endovascular balloon occlusion of the aorta (REBOA) represents an endovascular procedure for aortic occlusion. The procedure can be used for temporary hemorrhage control as a bridge until surgical treatment for noncompressible abdominal or pelvic bleeding and to improve coronary and cerebral perfusion pressure during cardiopulmonary resuscitation. The prehospital administration is challenging and currently hardly possible in Germany. In the REBOA in bleeding and cardiac arrest in the prehospital care by helicopter emergency medical service (RIBCAP-HEMS) project, the prehospital use of REBOA will be tested in a feasibility study. This article describes the training course on the procedure in preparation for prehospital use, which was conducted before the start of the aforementioned feasibility study for the emergency physicians and paramedics (HEMS-TC) of the DRF Air Rescue Base in Halle (Saale). The course provided the necessary theoretical and practical skills to apply REBOA in the prehospital setting to patients in extremis in a safe, indications-conform and time-critical manner. The fact that all emergency physicians of the two air ambulances Christoph 84 and Christoph 85 in Halle are specialists in anesthesiology with corresponding experience in the placement of invasive arterial catheters proved to be advantageous. The training course was able to significantly improve the theoretical and practical abilities of the participants. The results of the currently ongoing study must show whether the procedure can be usefully integrated into the prehospital care of patients in extremis.

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.

Development and usability testing of a fully immersive VR simulation for REBOA training

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a potentially life-saving procedure for bleeding trauma patients. Being a rare and complex procedure performed in extreme situations, repetitive training of REBOA teams is critical. Evidence-based guidelines on how to train REBOA are missing, although simulation-based training has been shown to be effective but can be costly and complex. We aimed to determine the feasibility and acceptance of REBOA training using a fully immersive virtual reality (VR) REBOA simulation, as well as assess the confidence in conducting the REBOA procedure before and after the training.

METHODS

Prospective feasibility pilot study of prehospital emergency physicians and paramedics in Bern, Switzerland, from November 2020 until March 2021. Baseline characteristics of trainees, prior training and experience in REBOA and with VR, variables of media use (usability: system usability scale, immersion/presence: Slater-Usoh-Steed, workload: NASA-TLX, user satisfaction: USEQ) as well as confidence prior and after VR training were accessed.

RESULTS

REBOA training in VR was found to be feasible without relevant VR-specific side-effects. Usability (SUS median 77.5, IQR 71.3-85) and sense of presence and immersion (Slater-Usoh-Steed median 4.8, IQR 3.8-5.5) were good, the workload without under-nor overstraining (NASA-TLX median 39, IQR 32.8-50.2) and user satisfaction high (USEQ median 26, IQR 23-29). Confidence of trainees in conducting REBOA increased significantly after training (p < 0.001).

CONCLUSIONS

Procedural training of the REBOA procedure in immersive virtual reality is possible with a good acceptance and high usability. REBOA VR training can be an important part of a training curriculum, with the virtual reality-specific advantages of a time- and instructor-independent learning.

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.

Do we need pre-hospital resuscitative endovascular balloon occlusion of the aorta (REBOA) in the civilian helicopter emergency medical services (HEMS)?

Pre-hospital resuscitative endovascular balloon occlusion of the aorta (REBOA) can be a life-saving procedure for patients with non-compressible torso hemorrhage. We aimed to evaluate the potential eligibility for REBOA in trauma patients of a civilian helicopter emergency medical service (HEMS) using a stepwise approach. A retrospective analysis using the electronic database (HEMSDER) of "DRF Luftrettung" HEMS covering the period from January 2015 to June 2021 was performed. Trauma patients aged ≥ 16 years and with a National Advisory Committee for Aeronautics (NACA) score of ≥ 4 were assessed for potential REBOA eligibility using two different decision trees based on assumed severe bleeding due to injuries of the abdomen, pelvis, and/or lower extremities and different vital signs on the scene and at hospital handover. Non-parametric statistical methods were used for comparison. A total of 22.426 patients met the inclusion criteria for data analysis. Of these, 0.15-2.24% were possible candidates for pre-hospital REBOA. No significant differences between groups on scene and at hospital handover regarding demographics, assumed injuries, and pre-hospital interventions were found. In the on-scene group, 21.1% of the patients remained unstable even at hospital handover despite pre-hospital care. In the handover group, 42.8% of the patients seemed initially stable but then deteriorated during the pre-hospital course. The number of potential pre-hospital REBOA in severely injured patients with a NACA score of ≥ 4 is < 3% or can be even < 1% if more strict criteria are used. There are some patients who may benefit from pre-hospital REBOA as a life-saving procedure. Further research on earlier diagnosis of life-threatening bleeding and proper indications of REBOA in trauma patients is needed.

Learning insertion of a Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) catheter: Is clinical experience necessary? A prospective trial

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emerging and potentially life-saving procedure, necessitating qualified operators in an increasing number of centres. The procedure shares technical elements with other vascular access procedures using the Seldinger technique, which is mastered by doctors not only in endovascular specialties but also in trauma surgery, emergency medicine, and anaesthesiology. We hypothesised that doctors mastering the Seldinger technique (experienced anaesthesiologist) would learn the technical aspects of REBOA with limited training and remain technically superior to doctors unfamiliar with the Seldinger technique (novice residents) given similar training.

METHODS

This was a prospective trial of an educational intervention. Three groups of doctors were enroled: novice residents, experienced anaesthesiologists, and endovascular experts. The novices and the anaesthesiologists completed 2.5 h of simulation-based REBOA training. Their skills were tested before and 8-12 weeks after training using a standardised simulated scenario. The endovascular experts, constituting a reference group, were equivalently tested. All performances were video recorded and rated by three blinded experts using a validated assessment tool for REBOA (REBOA-RATE). Performances were compared between groups and with a previously published pass/fail cutoff.

RESULTS

Sixteen novices, 13 board-certified specialists in anaesthesiology, and 13 endovascular experts participated. Before training, the anaesthesiologists outperformed the novices by 30 percentage points of the maximum REBOA-RATE score (56% (SD 14.0) vs 26% (SD 17%), p<0.01). After training, there was no difference in skills between the two groups (78% (SD 11%) vs 78 (SD 14%), p = 0.93). Neither group reached the endovascular experts' skill level (89% (SD 7%), p<0.05).

CONCLUSION

For doctors mastering the Seldinger technique, there was an initial inter-procedural transfer of skills advantage when performing REBOA. However, after identical simulation-based training, novices performed equally well to anaesthesiologists, indicating that vascular access experience is not a prerequisite to learning the technical aspects of REBOA. Both groups would need more training to reach technical proficiency.

Development of a post-mortem human specimen flow model for advanced bleeding control training

INTRODUCTION

Prompt and effective hemorrhage control is paramount to improve survival in patients with catastrophic bleeding. In the ever-expanding field of bleeding control techniques, there is a need for a realistic training model to practice these life-saving skills. This study aimed to create a realistic perfused post-mortem human specimen (PMHS) flow model that is suitable for training various bleeding control techniques.

MATERIALS AND METHODS

This laboratory study was conducted in the SkillsLab & Simulation Center of Erasmus MC, University Medical Center Rotterdam, the Netherlands. One fresh frozen and five AnubiFiX® embalmed PMHS were used for the development of the model. Subsequent improvements in the exact preparation and design of the flow model were made based on model performance and challenges that occurred during this study and are described.

RESULTS

Circulating arteriovenous flow with hypertonic saline was established throughout the entire body via inflow and outflow cannulas in the carotid artery and jugular vein of embalmed PMHS. We observed full circulation and major hemorrhage could be mimicked. Effective bleeding control was achieved by placing a resuscitative endovascular balloon occlusion of the aorta (REBOA) catheter in the model. Regional perfusion significantly reduced the development of tissue edema.

CONCLUSION

Our perfused PMHS model with circulating arterial and venous flow appears to be a feasible method for the training of multiple bleeding control techniques. Regional arteriovenous flow successfully reduces tissue edema and increases the durability of the model. Further research should focus on reducing edema and enhancing the durability of the model.

Multidisciplinary Simulation of Trauma in Pregnancy with Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) Utilization

Background Studies have demonstrated the use of resuscitative endovascular balloon occlusion catheters of the aorta (REBOA) in the setting of postpartum hemorrhage and traumatic hemorrhagic shock. However, REBOA is infrequently utilized leading to a lack of clinician comfort. This study's aim was to demonstrate the utility of REBOA in a hemorrhaging pregnant trauma patient and improve clinician comfort with the placement of REBOA while emphasizing collaboration between medical specialties. Methods A multidisciplinary in-situ simulation was developed for the management of a pregnant patient with an abdominal gunshot wound evaluated by obstetrics and surgery teams. A trauma survey, emergency c-section, massive transfusion protocol (MTP), and evaluation for and placement of REBOA were indicated during the simulation. A standardized Return on Learning questionnaire was utilized to determine participants' reactions and confidence gained during the simulation. Results A total of 32 of 41 participants completed the survey (78%). A statistically significant increase in confidence was reported in the ability to prioritize the care of a pregnant patient with hemorrhagic shock (p = 0.016), apply MTP to the appropriate clinical setting (p = 0.03), and analyze critical decisions made for abdominal trauma in pregnant patients (p = 0.006). Specifically for physicians, a significant increase in confidence in the ability to identify indications/contraindications for REBOA placement in hemorrhaging patients was observed (p = 0.021). Conclusions A multidisciplinary simulation for the management of a pregnant patient in hemorrhagic shock secondary to penetrating abdominal trauma improved learner confidence in MTP, care of pregnant patients in hemorrhagic shock, and abdominal trauma in pregnancy. Physician learners gained confidence in indications for REBOA placement in abdominal trauma. This simulation was highly relevant to all participants.

Resuscitative endovascular balloon occlusion of the aorta in civilian pre-hospital care: a systematic review of the literature

Background

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a damage control tool with a potential role in the hemodynamic resuscitation of severely ill patients in the civilian pre-hospital setting. REBOA ensures blood flow to vital organs by early proximal control of the source of bleeding. However, there is no consensus on the use of REBOA in the pre-hospital setting. This article aims to perform a systematic review of the literature about the feasibility, survival, indications, complications, and potential candidates for civilian pre-hospital REBOA.

Methods

A literature search was conducted using Medline, EMBASE, LILACS and Web of Science databases. Primary outcome variables included overall survival and feasibility. Secondary outcome variables included complications and potential candidates for endovascular occlusion.

Results

The search identified 8 articles. Five studies described the use of REBOA in pre-hospital settings, reporting a total of 47 patients in whom the procedure was attempted. Pre-hospital REBOA was feasible in 68–100% of trauma patients and 100% of non-traumatic patients with cardiac arrest. Survival rates and complications varied widely. Pre-hospital REBOA requires a coordinated and integrated emergency health care system with a well-trained and equipped team. The remaining three studies performed a retrospective analysis identifying 784 potential REBOA candidates.

Conclusions

Pre-hospital REBOA could be a feasible intervention for a significant portion of severely ill patients in the civilian setting. However, the evidence is limited. The impact of pre-hospital REBOA should be assessed in future studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40001-022-00836-3.

Resuscitative Endovascular Balloon Occlusion of the Aorta for Traumatic Cardiopulmonary Arrest in the Emergency Department: The First Case With Successful Return of Spontaneous Circulation in Taiwan

Exsanguinating torso hemorrhage is a leading cause of death in trauma patients. Bleeding leads to hypothermia, acidosis, and coagulopathy, the so-called "lethal triad," and creates a vicious cycle. Therefore, bleeding control tops the priority list in the management of trauma patients. Placement of resuscitative endovascular balloon occlusion of the aorta (REBOA) in patients with traumatic non-compressible torso hemorrhage is a developing technique in the emergency departments (EDs) in Taiwan, and it is a possible solution for abdominal and pelvic trauma patients with hemodynamic instability. It not only temporarily controls bleeding below the inflation site but also increases cerebral and coronary circulation. It can create a bridge for definitive care such as an operation or an embolization, possibly preventing death. Compared to thoracotomy followed by an aortic cross clamp, REBOA is a less invasive and possibly, a more efficient way to control the hemorrhage and may lead to better overall survival. The use of REBOA has been proven to be associated with improved survival-to-discharge in severely injured trauma patients. We report a case of out-of-hospital cardiac arrest caused by penetrating injury wherein return of spontaneous circulation was successfully achieved after 39-minute cardiopulmonary resuscitation and REBOA placement in the ED. The REBOA balloon was deflated after bleeding was stopped during the laparotomy operation. The patient was then transferred to the intensive care unit for postoperative care. Unfortunately, the patient passed away approximately 12 hours after the surgery.

Difference in postcourse knowledge and confidence between Web-based and on-site training courses on resuscitative endovascular balloon occlusion of the aorta

Aim

Effective courses are essential for highly invasive procedures such as resuscitative endovascular balloon occlusion of the aorta. However, the coronavirus disease pandemic has forced the postponement of on‐site educational courses due to transmission concerns. Few studies have examined the effectiveness of Web‐based education in highly invasive procedures. To address this knowledge gap, this study aimed to investigate whether knowledge acquisition and confidence after the Web‐based course are different from those acquired after the on‐site course, using pre‐ and postcourse test scores.

Methods

The increase in scores before and after the course was compared between the on‐site and Web‐based courses. The questions reflected knowledge about seven different topics in the course modules. In addition, participants were asked about their self‐rated confidence about three topics before and after the course.

Results

Thirty learners completed the on‐site course, and 21 learners completed the Web‐based course. Forty‐seven learners completed both the precourse and postcourse tests. In both courses, the difference between the precourse and postcourse test scores showed a statistically significant increase in knowledge (on‐site course: increased score, 1.8; 95% confidence interval, 0.8 to 2.8; Web‐based course: increased score, 1.6, 95% confidence interval, 0.5 to 2.5). However, the difference was not statistically significant in the self‐rated confidence scores about “sheath and catheter removal” among learners of the Web‐based course.

Conclusion

Knowledge increased significantly in both the on‐site and Web‐based courses. However, the Web‐based course might not be sufficient to give learners confidence in the procedures.

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.

High resuscitative endovascular balloon occlusion of the aorta procedural volume is associated with improved outcomes: An analysis of the AORTA registry

BACKGROUND

The use of resuscitative endovascular balloon occlusion of the aorta (REBOA) is controversial. We hypothesize that REBOA outcomes are improved in centers with high REBOA utilization.

METHODS

We examined the Aortic Occlusion in Resuscitation for Trauma and Acute Care Surgery registry over a 5-year period (2014-2018). Resuscitative endovascular balloon occlusion of the aorta outcomes were analyzed by stratifying institutions into low-volume (<10), average-volume (11-30), and high-volume (>30) deployment centers. A multivariable model adjusting for volume group, mechanism of injury, signs of life, systolic blood pressure at initiation, operator level, device type, zone of placement, and hemodynamic response to aortic occlusion was created to analyze REBOA mortality and REBOA-related complications.

RESULTS

Four hundred ninety-five REBOA placements were included. High-volume centers accounted for 63%, while low accounted for 13%. High-volume institutions were more likely to place a REBOA in the emergency department (81% vs. 63% low volume, p = 0.003), had a lower mean systolic blood pressure at insertion (53 ± 38 vs. 64 ± 40, p = 0.001), and more Zone I deployments (64% vs. 55%, p = 0.002). Median time from admission to REBOA placement was significantly less in patients treated at high-volume centers (15 [7-30] minutes vs. 35 [20-65] minutes, p = 0.001). Resuscitative endovascular balloon occlusion of the aorta mortality was significantly higher at low-volume centers (67% vs. 57%; adjusted odds ratio, 1.29; adj p = 0.040), while average- and high-volume centers were similar. Resuscitative endovascular balloon occlusion of the aorta complications were less frequent at high-/average-volume centers, but did not reach statistical significance (adj p = 0.784).

CONCLUSION

Resuscitative endovascular balloon occlusion of the aorta survival is increased at high versus low utilization centers. Increased experience with REBOA may be associated with earlier deployment and subsequently improved patient outcomes.

LEVEL OF EVIDENCE

Therapeutic/Care Management, level IV.

Management of non-compressible torso hemorrhage of the abdomen in civilian and military austere/remote environments: protocol for a scoping review

The management of non-compressible torso hemorrhage in military austere/remote environments is a leading cause of potentially preventable death in the prehospital/battlefield environment that has not shown a decrease in mortality in 26 years. Numerous conceptual innovations to manage non-compressible torso hemorrhage have been developed without proven effectiveness in this setting. This scoping review aims to assess the current literature to define non-compressible torso hemorrhage in civilian and military austere/remote environments, assess current innovations and the effectiveness of these innovations, assess the current knowledge gaps and potential future innovations in the management of non-compressible torso hemorrhage in civilian and military austere/remote environments, and assess the translational health science perspective of the current literature and its potential effect on public health. The Joanna Briggs Institute for evidence synthesis will guide this scoping review to completion. A nine-step development process, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist, will be used to enhance the methodological and reporting quality of this scoping review. The Participant, Concept, Context framework will broaden this scoping review's reach in developing a comprehensive search strategy. Thirty years will be explored to assess all relevant literature to ensure a thorough search. Two researchers will explore all the discovered literature and develop consensus on the selected literature included in this scoping review. The article will undergo review and data extraction for data analysis. The knowledge to action framework will guide the knowledge synthesis and creation of this scoping review. A narrative synthesis will systematically review and synthesize the collected literature to produce and explain a broad conclusion of the selected literature. Lastly, a consultation exercise in the form of qualitative interviews will be conducted to assess the thematic analysis results and validate the result of this scoping review. This scoping review will require Institutional Review Board approval for the expert consultation in the form of qualitative interviews. Consultants' identifying information will remain confidential. The collected and analyzed data from this scoping review will identify gaps in the literature to create an evidence-informed protocol for the management of non-compressible torso hemorrhage of the abdomen in civilian and military austere/remote environments. The results of this scoping review will be distributed in peer-reviewed journals and educational, medical presentations. Scoping Review Protocol, Level IV.

Reliable and valid assessment of procedural skills in resuscitative endovascular balloon occlusion of the aorta

BACKGROUND

Valid and reliable assessment of skills is essential for improved and evidence-based training concepts. In a recent study, we presented a novel tool to assess procedural skills in resuscitative endovascular balloon occlusion of the aorta (REBOA), REBOA-RATE, based on international expert consensus. Although expert consensus is a strong foundation, the performance of REBOA-RATE has not been explored. The study aimed to examine the reliability and validity of REBOA-RATE.

METHODS

This was an experimental simulation-based study. We enrolled doctors with three levels of expertise to perform two REBOA procedures in a simulated scenario of out-of-hospital cardiac arrest. Procedures were video-recorded, and videos were blinded and randomized. Three clinical experts independently rated all procedures using REBOA-RATE. Data were analyzed using Messick's framework for validity evidence, including generalizability analysis of reliability and determination of a pass/fail standard.

RESULTS

Forty-two doctors were enrolled: 16 novices, 13 anesthesiologists, and 13 endovascular experts. They all performed two procedures, yielding 84 procedures and 252 ratings. The REBOA-RATE assessment tool showed high internal consistency (Cronbach's α = 0.95) and excellent interrater reliability (intraclass correlation coefficient, 0.97). Assessment using one rater and three procedures could ensure overall reliability suitable for high-stakes testing (G-coefficient >0.80). Mean scores (SD) for the three groups in the second procedure were as follows: novices, 32% (24%); anesthesiologists, 55% (29%); endovascular experts, 93% (4%) (p < 0.001). The pass/fail standard was set at 81%, which all experts but no novices passed.

CONCLUSION

Data strongly support the reliability and validity of REBOA-RATE, which successfully discriminated between all experience levels. The REBOA-RATE assessment tool requires minimal instruction, and one rater is sufficient for reliable assessment. Together, these are strong arguments for the use of REBOA-RATE to assess REBOA skills, allowing for competency-based training and certification concepts.

LEVEL OF EVIDENCE

Diagnostic test, no or poor gold standard, level V.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) in patients with major trauma and uncontrolled haemorrhagic shock: a systematic review with meta-analysis

Background

Multiple studies regarding the use of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) in patients with non-compressible torso injuries and uncontrolled haemorrhagic shock were recently published. To date, the clinical evidence of the efficacy of REBOA is still debated. We aimed to conduct a systematic review assessing the clinical efficacy and safety of REBOA in patients with major trauma and uncontrolled haemorrhagic shock.

Methods

We systematically searched MEDLINE (PubMed), EMBASE and CENTRAL up to June 2020. All randomized controlled trials and observational studies that investigated the use of REBOA compared to resuscitative thoracotomy (RT) with/without REBOA or no-REBOA were eligible.

We followed the PRISMA and MOOSE guidelines. Two authors independently extracted data and appraised the risk of bias of included studies. Effect sizes were pooled in a meta-analysis using random-effects models. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation methodology. Primary outcomes were mortality, volume of infused blood components, health-related quality of life, time to haemorrhage control and any adverse effects. Secondary outcomes were improvement in haemodynamic status and failure/success of REBOA technique.

Results

We included 11 studies (5866 participants) ranging from fair to good quality. REBOA was associated with lower mortality when compared to RT (aOR 0.38; 95% CI 0.20–0.74), whereas no difference was observed when REBOA was compared to no-REBOA (aOR 1.40; 95% CI 0.79–2.46). No significant difference in health-related quality of life between REBOA and RT (p = 0.766). The most commonly reported complications were amputation, haematoma and pseudoaneurysm. Sparse data and heterogeneity of reporting for all other outcomes prevented any estimate.

Conclusions

Our findings on overall mortality suggest a positive effect of REBOA among non-compressible torso injuries when compared to RT but no differences compared to no-REBOA. Variability in indications and patient characteristics prevents any conclusion deserving further investigation. REBOA should be promoted in specific training programs in an experimental setting in order to test its effectiveness and a randomized trial should be planned.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13017-021-00386-9.

Developing a tool to assess competence in resuscitative endovascular balloon occlusion of the aorta: An international Delphi consensus study

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emergency procedure that is potentially lifesaving in major noncompressible torso hemorrhage. It may also improve outcome in nontraumatic cardiac arrest. However, the procedure can be technically challenging and requires the immediate presence of a qualified operator. Thus, evidence-based training and assessment of operator skills are essential for successful implementation and patient safety. A prerequisite for this is a valid and reliable assessment tool specific for the procedure. The aim of this study was to develop a tool for assessing procedural competence in REBOA based on best-available knowledge from international experts in the field.

METHODS

We invited international REBOA experts from multiple specialties to participate in an anonymous three-round iterative Delphi study to reach consensus on the design and content of an assessment tool. In round 1, participants suggested items to be included. In rounds 2 and 3, the relevance of each suggested item was evaluated by all participants to reach consensus. Interround data processing was done systematically by a steering group.

RESULTS

Forty panelists representing both clinical and educational expertise in REBOA from 16 countries (in Europe, Asia, and North and South America) and seven different specialties participated in the study. After 3 Delphi rounds and 532 initial item suggestions, the panelists reached consensus on a 10-item assessment tool with behaviorally anchored rating scales. It includes assessment of teamwork, procedure time, selection and preparation of equipment, puncture technique, guidewire handling, sheath handling, placement of REBOA catheter, occlusion, and evaluation.

CONCLUSION

We present the REBOA-RATE assessment tool developed systematically by international experts in the field to optimize content validity. Following further studies of its validity and reliability, this tool represents an important next step in evidence-based training programs in REBOA, for example, using mastery learning.

LEVEL OF EVIDENCE

Therapeutic, level V.

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) Use in Animal Trauma Models

BACKGROUND

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) was developed to prevent traumatic exsanguination. We aim to identify the outcomes in animal models with 1) partial versus complete REBOA occlusion and 2) zone 1 versus 2 placements.

METHODS

The PRISMA guidelines were followed. We conducted a search of PubMed, EMBASE and Google Scholar for REBOA studies in animal trauma models using the following search terms: "REBOA trauma", "REBOA outcomes" "REBOA complications". SYRCLE's RoB Tool was utilized for the risk of bias and study quality assessment.

RESULTS

Our search yielded 14 RCTs for inclusion. Eleven studies directly investigated partial REBOA versus total aortic occlusion. Overall, partial REBOA techniques were associated with similar attainment of proximal MAP but with significantly less ischemic burden. Significant mortality benefit with partial occlusion was observed in three studies. Survival time post-occlusion also was improved with zone 3 placement versus zone 1 (100% versus 33%; P < 0.01).

CONCLUSIONS

There appears to be a fine balance between desired proximal arterial pressure and time of occlusion for overall survival and subsequent risk of distal ischemia. Many "partial occlusion" techniques may be superior in attaining such balance over prolonged REBOA inflation where no distal flow is allowed. Tailored zone 3 placement may offer significant mortality and morbidity advantages compared to sustained total occlusion and indiscriminate zone 1 placement strategies. As clear conclusions regarding REBOA are unlikely to be established in animal models, larger randomized investigations utilizing human subjects are needed to describe optimal REBOA technique and applicability in greater detail.

Ultrasound-guided versus blind vascular access followed by REBOA on board of a medical helicopter in a hemorrhagic ovine model

BACKGROUND

The aim of this study is to evaluate the feasibility of en-route resuscitative endovascular balloon occlusion of the aorta (REBOA) on board of a helicopter.

METHODS

Six sedated male sheep (weighing 42-54 kg) underwent a controlled hemorrhage until the systolic blood pressure (BP) dropped to <90 mmHg, and were placed into a low capacity Eurocopter AS-350 (France). During the 30-minutes normal flight, every animal underwent blind (left side) and ultrasound-guided (US) (right side) vascular access (VA) to the femoral artery followed by REBOA: the first catheter (Rescue balloon, Japan) - into Zone I, the second one (MIT, Russia) - Zone III. In case of blind VA failure, an alternate US-puncture was attempted. Six experienced flight anesthetists were enrolled into the study. Vascular access and REBOA catheter placement (confirmed by X-Ray later) success rate and timing were recorded.

RESULTS

Among six blind punctures one was successful, 2/6 - were into the vein, 3/6 - completely failed and switched to US-punctures (making total number of US-punctures nine). Eight out of nine US-punctures were successful. However, correct wire insertion and sheath placement was performed in 1/6 animal in the 'blind' group and only in 6/9 animals in the 'US' group. It took a median of 65 seconds (range 5-260) for US-puncture and a median of 4 minutes to get the sheath in. Among the 9 VAs, there were 2 REBOA failures (1 ruptured balloon [MIT] and 1 mistaken vena cava placement primarily recognized by a sudden drop of BP and later confirmed by X-Ray). Five out of seven balloons were placed in a desired intra-aortic position: 4/5 in Zone I and 1/2 - in Zone III. A median time for a successful REBOA procedure was 5.0 (range 2.5-10.0) minutes (1 min after sheath placement).

CONCLUSION

Our study demonstrates the potential feasibility of the en-route REBOA which can be performed within 5 minutes. Ultrasound-guidance is critically important to achieve en-route VA.

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA): update and insights into current practices and future directions for research and implementation

Background

In this review, we assess the state of Resuscitative Endovascular Occlusion of the Aorta (REBOA) today with respect to out-of-hospital (OOH) vs. inhospital (H) use in blunt and penetrating trauma, as well as discuss areas of promising research that may be key in further advancement of REBOA applications.

Methods

To analyze the trends in REBOA use, we conducted a review of the literature and identified articles with human or animal data that fit the respective inclusion and exclusion criteria. In separate tables, we compiled data extracted from selected articles in categories including injury type, zone and duration of REBOA, setting in which REBOA was performed, sample size, age, sex and outcome. Based on these tables as well as more detailed review of some key cases of REBOA usage, we assessed the current state of REBOA as well as coagulation and histological disturbances associated with its usage. All statistical tests were 2-sided using an alpha=0.05 for significance. Analysis was done using SAS 9.5 (Cary, NC). Tests for significance was done with a t-test for continuous data and a Chi Square Test for categorical data.

Results

In a total of 44 cases performed outside of a hospital in both military and civilian settings, the overall survival was found to be 88.6%, significantly higher than the 50.4% survival calculated from 1,807 cases of REBOA performed within a hospital (p<.0001). We observe from human data a propensity to use Zone I in penetrating trauma and Zone III in blunt injuries. We observe lower final metabolic markers in animal studies with shorter REBOA time and longer follow-up times.

Conclusions

Further research related to human use of REBOA must be focused on earlier initiation of REBOA after injury which may depend on development of rapid vascular access devices and techniques more so than on any new improvements in REBOA. Future animal studies should provide detailed multisystem organ assessment to accurately define organ injury and metabolic burden associated with REBOA application. Overall, animal studies must involve realistic models of injury with severe clinical scenarios approximating human trauma and exsanguination, especially with long-term follow-up after injury.

Successfully REBOA performance: does medical specialty matter? International data from the ABOTrauma Registry

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a minimally invasive procedure being increasingly utilized to prevent patients with non-compressible torso hemorrhage from exsanguination. The increased use of REBOA is giving rise to discussion about "Who is and who should be performing it?"

METHODS

Data from the international ABO (aortic balloon occlusion) Trauma Registry from between November 2014 and April 2020 were analyzed concerning the question: By who, how, and where is REBOA being performed? The registry collects retrospective and prospective data concerning use of REBOA in trauma patients.

RESULTS

During the study period, 259 patients had been recorded in the registry, 72.5% (n = 188) were males with a median (range) age of 46 (10-96) years. REBOA was performed in the ER in 50.5%, in the OR in 41.5%, and in the angiography suite in 8% of patients. In 54% of the patients REBOA was performed by surgeons (trauma surgeons 28%, vascular surgeons 22%, general surgeons 4%) and in 46% of the patients by non-surgeons (emergency physicians 31%, radiologists 9.5%, anesthetists 5.5%). Common femoral artery (CFA) access was achieved by use of external anatomic landmarks and palpation alone in 119 patients (51%), by cutdown in 57 patients (24%), using ultrasound in 49 patients (21%), and by fluoroscopy in 9 patients (4%). Significant differences between surgeons and non-surgeons were found regarding patient's age, injury severity, access methods, place where REBOA was performed, location patients were taken to from the emergency room, and mortality.

CONCLUSION

A substantial number of both surgical and non-surgical medical disciplines are successfully performing REBOA to an almost equal extent. Surgical cutdown is used less frequently as access to the CFA compared with reports in older literature and puncture by use of external anatomic landmarks and palpation alone is used with a high rate of success. Instead of discussing "Who should be performing REBOA?" future research should focus on "Which patient benefits most from REBOA?"

Can Resuscitative Endovascular Balloon Occlusion of the Aorta Fly? Assessing Aortic Balloon Performance for Aeromedical Evacuation

BACKGROUND

Noncompressible torso hemorrhage remains a leading cause of death. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) placement may occur before transport; however, its efficacy has not been demonstrated at altitude. We hypothesized that changes in altitude would not result in blood pressure changes proximal to a deployed REBOA.

METHODS

A simulation model for 7Fr guidewireless REBOA was used at altitudes up to 22,000 feet. Female pigs then underwent hemorrhagic shock to a mean arterial pressure (MAP) of 40 mm Hg. After hemorrhage, a REBOA catheter was deployed in the REBOA group and positioned but not inflated in the no-REBOA group. Animals underwent simulated aeromedical evacuation at 8000 ft or were left at ground level. After altitude exposure, the balloon was deflated, and the animals were observed.

RESULTS

Taking the REBOA catheter to 22,000 ft in the simulation model resulted in a lower systolic blood pressure but a preserved MAP. In the porcine model, REBOA increased both systolic blood pressure and MAP compared with no-REBOA (P < 0.05) and was unaffected by altitude. No differences in postflight blood pressure, acidosis, or systemic inflammatory response were observed between ground and altitude REBOA groups.

CONCLUSIONS

REBOA maintained MAP up to 22,000 feet in an inanimate model. In the porcine model, REBOA deployment improved MAP, and the balloon remained effective at altitude.