Fewer REBOA complications with smaller devices and partial occlusion: evidence from a multicentre registry in Japan

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) in the Field Setting: A Case Report From China

BACKGROUND

The widespread use of agricultural machinery in China has increased the incidence of agricultural machinery-related injuries, posing challenges to on-site medical rescue. This study explores resuscitative endovascular balloon occlusion of the aorta (REBOA) as a life-saving intervention for a patient with severe trauma from agricultural machinery.

CASEPRESENTATION

This study reviews the emergency medical response for a 70-year-old male who suffered machinery entanglement injuries in an agricultural field in western China. The intervention involved a tiered multidisciplinary medical response, including the implementation of REBOA.

CONCLUSION

This case demonstrates the successful use of REBOA in the prehospital setting in China. While prehospital REBOA use is rare, it is increasingly reported in both military and civilian contexts in austere environments in different countries. Further research is required to validate the feasibility and efficacy of REBOA as a prehospital resuscitation strategy.

Emergency treatment of pelvic ring injuries: state of the art

High energy pelvic injuries sustain significant mortality rates, due to acute exsanguination and severe associated injuries. Managing the hemodynamically unstable trauma patient with a bleeding pelvic fracture still forms a major challenge in acute trauma care. Various approaches have been applied through the last decades. At present the concept of Damage Control Resuscitation (DCR) is universally accepted and applied in major trauma centers internationally. DCR combines hemostatic blood transfusions to restore blood volume and physiologic stability, reduced crystalloid fluid administration, permissive hypotension, and immediate hemorrhage control by operative or angiographic means. Different detailed algorithms and orders of hemostatic procedures exist, without clear consensus or guidelines, depending on local traditions and institutional setups. Fracture reduction and immediate stabilization with a binder constitute the basis for angiography and embolization (AE) or pelvic packing (PP) in the hemodynamically unstable patient. AE is time consuming and may not be available 24/7, whereas PP offers a quick and technically easy procedure well suited for the patient in extremis. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has also been described as a valuable adjunct in hemostatic non-responders, but merely constitute a bridge to surgical or angiographic hemostasis and its definitive role in DCR is not yet clearly established. A swift algorithmic approach to the hemodynamically unstable pelvic injury patient is required to achieve optimum results. The present paper summarizes the available literature on the acute management of the bleeding pelvic trauma patient, with emphasis on initial assessment and damage control resuscitation including surgical and angiographic hemostatic procedures. Furthermore, initial treatment of open fractures and associated injuries to the nervous and genitourinary system is outlined.

Torso hemorrhage: noncompressible? never say never

Since limb bleeding has been well managed by extremity tourniquets, the management of exsanguinating torso hemorrhage (TH) has become a hot issue both in military and civilian medicine. Conventional hemostatic techniques are ineffective for managing traumatic bleeding of organs and vessels within the torso due to the anatomical features. The designation of noncompressible torso hemorrhage (NCTH) marks a significant step in investigating the injury mechanisms and developing effective methods for bleeding control. Special tourniquets such as abdominal aortic and junctional tourniquet and SAM junctional tourniquet designed for NCTH have been approved by FDA for clinical use. Combat ready clamp and junctional emergency treatment tool also exhibit potential for external NCTH control. In addition, resuscitative endovascular balloon occlusion of the aorta (REBOA) further provides an endovascular solution to alleviate the challenges of NCTH treatment. Notably, NCTH cognitive surveys have revealed that medical staff have deficiencies in understanding relevant concepts and treatment abilities. The stereotypical interpretation of NCTH naming, particularly the term noncompressible, is the root cause of this issue. This review discusses the dynamic relationship between TH and NCTH by tracing the development of external NCTH control techniques. The authors propose to further subdivide the existing NCTH into compressible torso hemorrhage and NCTH' (noncompressible but REBOA controllable) based on whether hemostasis is available via external compression. Finally, due to the irreplaceability of special tourniquets during the prehospital stage, the authors emphasize the importance of a package program to improve the efficacy and safety of external NCTH control. This program includes the promotion of tourniquet redesign and hemostatic strategies, personnel reeducation, and complications prevention.

Balloon Rises Above: REBOA at Zone 1 May Be Superior to Resuscitative Thoracotomy

BACKGROUND

The use of Zone 1 REBOA for life-threatening trauma has increased dramatically.

STUDY DESIGN

The Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery database was queried for blunt and penetrating trauma between 2013 and 2021. Outcomes were examined both for mechanisms of injury combined and separately and for combinations of abdominal injury with and without traumatic brain injury and chest injuries (Abbreviated Injury Scale [AIS] score >2).

RESULTS

A total of 531 patients underwent REBOA (408 with blunt injury and 123 with penetrating injury) and 1,603 (595 with blunt injury and 1,008 with penetrating injury) underwent resuscitative thoracotomy (RT). Mean age was 38.5 ± 16 years and mean injury severity score was 34.5 ± 21; 57.7% had chest AIS score of more than 2, 21.8% had head AIS score of more than 2, and 37.3% had abdominal AIS score of more than 2. Admission Glasgow Coma Scale was 4.9 + 4, and systolic blood pressure at aortic occlusion (AO) was 22 + 40 mmHg. No differences in outcomes in REBOA or RT patients were identified between institutions (p > 0.5). After inverse probability weighting, Glasgow Coma Scale, age, injury severity score, systolic blood pressure at AO, CPR at AO, and blood product transfusion, REBOA was superior to RT in both blunt (odds ratio [OR] 4.7, 95% CI 1.9 to 11.7) and penetrating (OR 4.9, 95% CI 1.7 to 14) injuries, across all spectrums of injury (p < 0.01). Overall mortality was significantly higher for AO more than 90 minutes compared with less than 30 minutes in blunt (OR 4.6, 95% CI 1.5 to 15) and penetrating (OR 5.4, 95% CI 1.1 to 25) injuries. Duration of AO more than 60 minutes was significantly associated with mortality after penetrating abdominal injury (OR 5.1, 95% CI 1.1 to 22) and abdomen and head (OR 5.3, 95% CI 1.6 to 18).

CONCLUSIONS

In-hospital survival is higher for patients undergoing REBOA than RT for all injury patterns. Complete AO by REBOA or RT should be limited to less than 30 minutes. Neither hospital and procedure volume nor trauma verification level impacts outcomes for REBOA or RT.

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) prior to interfacility transfer: Who might benefit in a statewide trauma system?

BACKGROUND

Rural trauma patients are often seen at lower-level trauma centers before transfer and have higher mortality than those seen initially at a Level 1 Trauma Center. This study aims to describe the potential for Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) to bridge this mortality gap.

METHODS

We queried the Arizona Trauma Registry between 2014 and 2017 for hypotensive patients who were later transported to a level 1 center. REBOA candidates were identified as those with injuries consistent with major infra-diaphragmatic torso hemorrhage as the likely cause of death.

RESULTS

Of 17,868 interfacility transfers during the study period, 333 met inclusion criteria and had sufficient data for evaluation. 26 of the 333 patients were identified as REBOA candidates.

CONCLUSIONS

Our study suggests that REBOA may be an effective means to extend survivability to those severely injured trauma patients needing interfacility transfer to a higher level of care.

Arterial Access Complications Following Percutaneous Femoral Access in 24-Hour Resuscitative Endovascular Balloon Occlusion of the Aorta Survivors

INTRODUCTION

With the use of resuscitative endovascular balloon occlusion of the aorta (REBOA) comes the potential for vascular access site complications (VASCs) and limb ischemic sequelae. We aimed to determine the prevalence of VASC and associated clinical and technical factors.

METHODS

A retrospective cohort analysis of 24-h survivors undergoing percutaneous REBOA via the femoral artery in the American Association for the Surgery of Trauma Aortic Occlusion for Resuscitation in Trauma and Acute care surgery registry between Oct 2013 and Sep 2021 was performed. The primary outcome was VASC, defined as at least one of the following: hematoma, pseudoaneurysm, arteriovenous fistula, arterial stenosis, or the use of patch angioplasty for arterial closure. Associated clinical and procedural variables were examined. Data were analyzed using Fisher exact test, Mann-Whitney-U tests, and linear regression.

RESULTS

There were 34 (7%) cases with VASC among 485 meeting inclusion criteria. Hematoma (40%) was the most common, followed by pseudoaneurysm (26%) and patch angioplasty (21%). No differences in demographics or injury/shock severity were noted between cases with and without VASC. The use of ultrasound (US) was protective (VASC, 35% versus no VASC, 51%; P = 0.05). The VASC rate in US cases was 12/242 (5%) versus 22/240 (9.2%) without US. Arterial sheath size >7 Fr was not associated with VASC. US use increased over time (R2 = 0.94, P < 0.001) with a stable rate of VASC (R2 = 0.78, P = 0.61). VASC were associated with limb ischemia (VASC, 15% versus no VASC, 4%; P = 0.006) and arterial bypass procedures (VASC 3% versus no VASC 0%; P < 0.001) but amputation was uncommon (VASC, 3% versus no VASC, 0.4%; P = 0.07).

CONCLUSIONS

Percutaneous femoral REBOA had a 7% VASC rate which was stable over time. VASC are associated with limb ischemia but need for surgical intervention and/or amputation is rare. The use of US-guided access appears to be protective against VASC and is recommended for use in all percutaneous femoral REBOA procedures.

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.

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.

A randomized porcine study of hemorrhagic shock comparing end-tidal carbon dioxide targeted and proximal systolic blood pressure targeted partial resuscitative endovascular balloon occlusion of the aorta in the mitigation of metabolic injury

BACKGROUND

The definition of partial resuscitative endovascular balloon occlusion of the aorta (pREBOA) is not yet determined and clinical markers of the degree of occlusion, metabolic effects and end-organ injury that are clinically monitored in real time are lacking. The aim of the study was to test the hypothesis that end-tidal carbon dioxide (ETCO₂) targeted pREBOA causes less metabolic disturbance compared to proximal systolic blood pressure (SBP) targeted pREBOA in a porcine model of hemorrhagic shock.

MATERIALS AND METHODS

Twenty anesthetized pigs (26-35 kg) were randomized to 45 min of either ETCO₂ targeted pREBOA (pREBOA_ETCO2, ETCO₂ 90-110% of values before start of occlusion, n = 10) or proximal SBP targeted pREBOA (pREBOA_SBP, SBP 80-100 mmHg, n = 10), during controlled grade IV hemorrhagic shock. Autotransfusion and reperfusion over 3 h followed. Hemodynamic and respiratory parameters, blood samples and jejunal specimens were analyzed.

RESULTS

ETCO₂ was significantly higher in the pREBOA_ETCO2 group during the occlusion compared to the pREBOA_SBP group, whereas SBP, femoral arterial mean pressure and abdominal aortic blood flow were similar. During reperfusion, arterial and mesenteric lactate, plasma creatinine and plasma troponin concentrations were higher in the pREBOA_SBP group.

CONCLUSIONS

In a porcine model of hemorrhagic shock, ETCO₂ targeted pREBOA caused less metabolic disturbance and end-organ damage compared to proximal SBP targeted pREBOA, with no disadvantageous hemodynamic impact. End-tidal CO₂ should be investigated in clinical studies as a complementary clinical tool for mitigating ischemic-reperfusion injury when using pREBOA.

Partial vs Full Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) in a Swine Model of Raised Intracranial Pressure and Hemorrhagic Shock

BACKGROUND

Partial resuscitative endovascular balloon occlusion of the aorta (pREBOA) is a potential method to mitigate the ischemia observed in full REBOA (fREBOA). However, the effect of pREBOA on cerebral perfusion in the setting of raised intracranial pressure (rICP) is unknown. The aim was to evaluate the effects of no REBOA (nREBOA) vs pREBOA vs fREBOA on cerebral perfusion in a swine model of rICP and hemorrhagic shock.

STUDY DESIGN

Anesthetized swine (n = 18) underwent instrumentation. Controlled hemorrhage was performed over 30 minutes. rICP was achieved using an intracranial Fogarty catheter inflated to achieve an ICP of 20 mmHg. Animals underwent intervention for 30 minutes, followed by resuscitation. The primary outcome was cerebral perfusion measured by ICP (millimeters of mercury), cerebral perfusion pressure (CPP; millimeters of mercury), and cerebral blood flow (CBF; milliliters per minute per 100 g) derived from CT perfusion. The secondary outcomes included hemodynamics and lactate (millimoles per liter).

RESULTS

The peak ICP of pREBOA animals (22.7 ± 2.5) was significantly lower than nREBOA and fREBOA. pREBOA CPP was significantly higher compared with nREBOA and fREBOA during resuscitation. The pREBOA CBF was greater during intervention and resuscitation compared with nREBOA (p < 0.001). Systolic blood pressure was similar between pREBOA and fREBOA, and coronary perfusion was significantly greater in pREBOA. fREBOA had significantly higher lactate during the intervention (9.3 ± 1.3) and resuscitation (8.9 ± 3.5) compared with nREBOA and pREBOA.

CONCLUSION

pREBOA produced greater cerebral perfusion, as demonstrated by more favorable CPP, CBF, and ICP values. fREBOA was associated with metabolic derangement and diminished pressure during resuscitation. pREBOA is superior to fREBOA in a swine model and should be considered over fREBOA for aortic occlusion.

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.

Intermittent thoracic resuscitative endovascular balloon occlusion of the aorta improves renal function compared to 60 min continuous application after porcine class III hemorrhage

Background

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) may be considered for stabilization of patients with hemorrhage from below the diaphragm. Occluding the aorta is a powerful means of hemorrhagic control but is also associated with acute kidney injury, which increases mortality in trauma patients. Allowing for intermittent distal blood flow during REBOA application (iREBOA) could decrease this risk, but circulatory consequences have not been sufficiently elucidated. Therefore, we investigated circulatory effects and the renal artery blood flow (RBF) in iREBOA versus continuous, complete aortic occlusion (cREBOA).

Methods

In a porcine model of uncontrolled class III hemorrhage (34% estimated total blood volume, mean 1360 mL), swine (n = 12, mean weight 60.3 kg) were randomly assigned to iREBOA: 3-min full deflation every 10 min (n = 6), or cREBOA (n = 6), for 60 min of thoracic (zone I) application. The animals then underwent 60 min of reperfusion (critical care phase).

Results

Survival was 100% in iREBOA and 83% in cREBOA. The intermittent balloon deflation protocol was hemodynamically tolerable in 63% of reperfusion intervals. Systolic blood pressure decreased during the reperfusion intervals in iREBOA animals (mean 108 mm Hg versus 169 mm Hg; p < 0.005). No differences were detected in heart rate, cardiac output or stroke volume between methods. Troponin I increased in cREBOA after 60 min (mean 666–187 ng/L, p < 0.05). The norepinephrine requirement increased in cREBOA during reperfusion (mean infusion time 12.5–5.5 min; p < 0.05). Total ischemic time decreased in iREBOA (60.0–48.6 min; p < 0.001). RBF increased in iREBOA during balloon deflations and after 60 min reperfusion (61%–39% of baseline RBF; p < 0.05). Urine output increased in iREBOA (mean 135–17 mL; p < 0.001). Nephronal osteopontin, a marker of ischemic injury, increased in cREBOA (p < 0.05).

Conclusion

iREBOA was survivable, did not cause rebleeding, decreased the total ischemic time and increased the renal blood flow, urine output and decreased renal ischemic injury compared to cREBOA. Intermittent reperfusions during REBOA may be preferred to be continuous, complete occlusion in prolonged application to improve renal function.

Endovascular Perfusion Augmentation After Resuscitative Endovascular Balloon Occlusion of the Aorta Improves Renal Perfusion and Decreases Vasopressors

INTRODUCTION

Resuscitative endovascular balloon occlusion of the aorta (REBOA) causes a severe ischemia-reperfusion injury. Endovascular Perfusion Augmentation for Critical Care (EPACC) has emerged as a hemodynamic/mechanical adjunct to vasopressors and crystalloid for the treatment of post-REBOA ischemia-reperfusion injury. The objective of the study is to examine the impact of EPACC as a tool for a wean from complete REBOA compared to standard resuscitation techniques.

METHODS

Nine swine underwent anesthesia and then a controlled 30% blood volume hemorrhage with 30 min of supraceliac total aortic occlusion to create an ischemia-reperfusion injury. Animals were randomized to standardized critical care (SCC) or 90 min of EPACC followed by SCC. The critical care phase lasted 270 min after injury. Hemodynamic markers and laboratory values of ischemia were recorded.

RESULTS

During the first 90 min the intervention phase SCC spent 60% (54%-73%) and EPACC spent 91% (88%-92%) of the time avoiding proximal hypotension (<60 mm Hg), P = 0.03. There was also a statistically significant decrease in cumulative norepinephrine dose at the end of the experiment between SCC (80.89 mcg/kg) versus EPACC (22.03 mcg/kg), P = 0.03. Renal artery flow during EPACC was similar compared to SCC during EPACC, P = 0.19. But during the last hour of the experiment (after removal of aortic balloon) the renal artery flow in EPACC (2.9 mL/kg/min) was statistically significantly increased compared to SCC (1.57 mL/min/kg), P = 0.03. There was a statistically significant decrease in terminal creatinine in the EPACC (1.7 mg/dL) compared to SCC (2.1 mg/dL), P = 0.03.

CONCLUSIONS

The 90 min of EPACC as a weaning adjunct in the setting of a severe ischemia-reperfusion injury after complete supraceliac REBOA provides improved renal flow with improvement in terminal creatinine compared to SCC with stabilized proximal hemodynamics and decreased vasopressor dose.

Resuscitative endovascular balloon occlusion of the aorta for life-threatening postpartum hemorrhage: A nationwide observational study in Japan

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is used for postpartum hemorrhage (PPH) which is one of the leading causes of maternal mortality worldwide; however, its utility in the obstetrics setting remains unclear. Thus, this study aimed to describe the characteristics, demographics and mortality of patients with PPH who underwent REBOA.

METHODS

We used the Japanese Diagnosis Procedure Combination inpatient database to identify patients with PPH who underwent REBOA from April 2012 to March 2020. We examined the patients' characteristics, interventions administered and in-hospital mortality.

RESULTS

We identified 143 patients with PPH who underwent REBOA. The most common cause of PPH was atonic postpartum hemorrhage (52.4%), followed by disseminated intravascular coagulation (29.4%) and amniotic fluid embolism documented (11.2%). Among patients who delivered at hospitals in which REBOA was performed (n = 55), 38.2% of patients experienced preterm births and 70.9% delivered via cesarean section. The proportion of patients who underwent transcatheter arterial embolization and hysterectomy was 53.8% and 16.1%, respectively. In-hospital mortality was 7.0%.

CONCLUSION

The results of the present study could be helpful in clinical decision-making and providing patients and families with additional treatment options for PPH.

LEVEL OF EVIDENCE

Therapeutic, level IV.

Successful Management of Resuscitative Endovascular Balloon Occlusion of the Aorta for Hemorrhagic Shock Due to Ruptured Hepatocellular Carcinoma

A 68-year-old man was transferred to our hospital because of sudden right costal pain with unmeasurable hypotension. Ultrasonography revealed possible hemorrhagic shock due to ruptured hepatocellular carcinoma (HCC). As the patient was not hemodynamically stable after primary treatment, resuscitative endovascular balloon occlusion of the aorta (REBOA) was performed, and hemodynamic stability was then achieved. Contrast-enhanced computed tomography confirmed the diagnosis. Transcatheter artery embolization with gelatin sponge particles and coils eliminated the extravasation. The patient was discharged on day 36 post-procedure. Our observations suggest that REBOA may help achieve hemodynamic stability in cases of ruptured HCC.

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

INTRODUCTION

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been used as a bridge to definitive bleeding control of subdiaphragmatic injury. Since previous observational studies have poorly adjusted for confounding factors, it is necessary to incorporate REBOA-specific and time-varying covariates in the model. We hypothesised that REBOA improves the survival of haemodynamically unstable torso trauma patients after comparing the REBOA group with a matched control group (non-REBOA group).

METHODS AND ANALYSIS

The Japanese Association for the Surgery of Trauma-REBOA Study is a prospective, multicentre, matched cohort study organised by the Clinical Trial Committee of the Japanese Association for the Surgery of Trauma. To minimise observational study biases, this study will prospectively register traumatic shock patients who require bleeding control within 60 min upon arrival at the emergency department, with in-hospital mortality as the primary outcome. After the data set is fixed, the missing values for all variables will be imputed using the multiple imputation technique. In the primary analysis, propensity scores for the probability of REBOA decision (regardless of the actual REBOA deployment) will be calculated from the baseline information using a logistic regression generalised linear mixed-effects model, which will be performed for both the REBOA use and non-REBOA use groups.

ETHICS AND DISSEMINATION

This study was approved by the ethics committee of each participating hospital. The results will be disseminated to the participating hospitals, submitted to peer-reviewed journals for publication and presented at congresses.

TRIAL REGISTRATION NUMBER

UMIN Clinical Trials Registry (UMIN000035458).

REBOA utility

Resuscitative endovascular balloon occlusion of the aorta is a tool that can play an important role for the modern-day Trauma Surgeon. Although the concept of aortic balloon occlusion is not new, its use as a rescue device for managing life-threatening traumatic hemorrhage has increased dramatically. The ideal role for resuscitative endovascular balloon occlusion of the aorta continues to evolve. In situations of noncompressible truncal hemorrhage, its use can temporize bleeding while other means of hemorrhage control, including those discussed elsewhere in this supplement, are used. However, it is a tool with potentially significant complications and consequences. Studies examining resuscitative endovascular balloon occlusion of the aorta are ongoing as, despite its ever-increasing adoption, quality evidence to support its clinical use is lacking.

The Role of Prehospital REBOA for Hemorrhage Control in Civilian and Military Austere Settings: A Systematic Review

Despite the success of prehospital resuscitative endovascular balloon occlusion of the aorta (REBOA) in combat and civilian settings, the prevalence of complications and the lack of conclusive evidence has led to uncertainty and controversy. Therefore, this systematic review aimed to evaluate the role of prehospital REBOA for hemorrhage control in trauma populations. We systematically searched Cochrane, Ovid MEDLINE, EMBASE and Google Scholar for all relevant studies that investigated the efficacy of prehospital REBOA on trauma patients with massive hemorrhage. Primary outcome was evaluated by blood pressure elevation and secondary outcome was measured by 30-day mortality and complications. Our search identified 546 studies, but only six studies met the inclusion and exclusion criteria. Included studies were low to moderate quality due to limitations within the studies. However, all of the studies reported significant elevation of blood pressure and survival, demonstrating the potential benefits of REBOA. For example, the 30-day mortality rate reduced significantly after REBOA, but studies lacked long-term outcome assessments across the continuum of care. Due to the heterogeneity of the results, a meta-analysis was not possible. We conclude that prehospital REBOA is a feasible and effective resuscitative adjunct for shock patients with lethal non-compressible torso hemorrhage. However, due to the unclear causes of complications and the lack of high quality and homogeneous data, the effects of prehospital REBOA were not truly reflected and comparison between groups was not feasible. Thus, further high-quality studies are required to attest the causality between prehospital REBOA and outcomes.

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) in Non-Traumatic Cardiac Arrest: A Narrative Review of Known and Potential Physiological Effects

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is widely used in acute trauma care worldwide and has recently been proposed as an adjunct to standard treatments during cardiopulmonary resuscitation in patients with non-traumatic cardiac arrest (NTCA). Several case series have been published highlighting promising results, and further trials are starting. REBOA during CPR increases cerebral and coronary perfusion pressure by increasing the afterload of the left ventricle, thus improving the chances of ROSC and decreasing hypoperfusion to the brain. In addition, it may facilitate the termination of malignant arrhythmias by stimulating baroreceptor reflex. Aortic occlusion could mitigate the detrimental neurological effects of adrenaline, not only by increasing cerebral perfusion but also reducing the blood dilution of the drug, allowing the use of lower doses. Finally, the use of a catheter could allow more precise hemodynamic monitoring during CPR and a faster transition to ECPR. In conclusion, REBOA in NTCA is a feasible technique also in the prehospital setting, and its use deserves further studies, especially in terms of survival and good neurological outcome, particularly in resource-limited settings.

A core outcome set for resuscitative endovascular balloon occlusion of the aorta: A consensus based approach using a modified Delphi method

BACKGROUND

The utilization of resuscitative endovascular balloon occlusion of the aorta (REBOA) in trauma has grown exponentially in recent years. However, inconsistency in reporting of outcome metrics related to this intervention has inhibited the development of evidence-based guidelines for REBOA application. This study sought to attain consensus on a core outcome set (COS) for REBOA.

METHODS

A review of "landmark" REBOA articles was performed, and panelists (first and senior authors) were contacted for participation in a modified Delphi study. In round 1, panelists provided a list of potential core outcomes. In round 2, using a Likert scale (1 [not important] to 9 [very important]), panelists scored the importance of each potential outcome. Consensus for core outcomes was defined a priori as greater than 70% of scores receiving 7 to 9 and less than 15% of scores receiving 1 to 3. Feedback was provided after round 2, and a third round was performed to reevaluate variables not achieving consensus and allow a final "write-in" round by the experts.

RESULTS

From 17 identified panelists, 12 participated. All panelists (12 of 12, 100%) participated in each subsequent round. Panelists initially identified 34 unique outcomes, with two outcomes later added upon write-in request after round 2. From 36 total potential outcomes, 20 achieved consensus as core outcomes, and this was endorsed by 100% of the participants.

CONCLUSION

Panelists successfully achieved consensus on a COS for REBOA-related research. This REBOA-COS is recommended for all clinical trials related to REBOA and should help enable higher-quality study designs, valid aggregation of published data, and development of evidence-based practice management guidelines.

LEVEL OF EVIDENCE

Diagnostic test or criteria, level V.

TRIAL REGISTRATION

Core Outcomes in Trauma Surgery: Development of a Core Outcome Set for Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) http://www.comet-initiative.org/Studies/Details/1709.

Fetal and neonatal outcomes following maternal aortic balloon occlusion for hemorrhage in pregnancy: A review of the literature

BACKGROUND

Hemorrhage is a leading cause of maternal death worldwide, with increased risk in women with abnormal placentation. Aortic balloon occlusion (ABO), including resuscitative endovascular balloon occlusion, has been used for obstetrical hemorrhage for 20 years, and is associated with decreased operative blood loss, fewer transfusions, and lower rates of hysterectomy. However, the effect of aortic occlusion on fetal/neonatal outcomes is not well known.

METHODS

A literature review on ABO for obstetrical or traumatic hemorrhage was performed. Cases were included if fetal/neonatal outcomes were reported. Data were collected on timing of balloon inflation (predelivery or postdelivery), fetal/neonatal mortality, and Apgar scores. Secondary maternal outcomes included blood loss, need for hysterectomy, ABO-related complications, and mortality.

RESULTS

Twenty-one reports of ABO in 825 cases of obstetrical hemorrhage were reviewed (nine case reports/series and twelve comparative studies). 13.5% (111/825) had aortic occlusion prior to delivery of the fetus. Comparative cohorts included 448 patients who underwent iliac artery balloon occlusion (n = 219) or no vascular balloon occlusion (n = 229). The most common neonatal outcome reported was Apgar scores, with no difference in fetal/neonatal outcomes between ABO and non-ABO patients in any study. One neonatal mortality occurred in the sole reported case of ABO use in a pregnant trauma patient at 24 weeks gestation. One maternal mortality occurred because of aortic dissection. Five comparative studies reported significantly decreased blood loss in ABO patients compared to non-ABO patients, and four studies reported significantly lower rates of hysterectomy in ABO patients. ABO-related complications were reported in 1.6% of patients (13/825).

CONCLUSION

Obstetrical hemorrhage is a devastating complication, and ABO may potentially decrease blood loss and reduce the hysterectomy rate without compromising fetal and neonatal outcomes. Further research is needed to determine the safety of predelivery aortic occlusion as this occurred in 14% of the cases.

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.

Targeted Regional Optimization: Increasing the Therapeutic Window for Endovascular Aortic Occlusion In Traumatic Hemorrhage

ABSTRACT

Resuscitative endovascular balloon occlusion of the aorta (REBOA) allows for effective temporization of exsanguination from non-compressible hemorrhage (NCTH) below the diaphragm. However, the therapeutic window for aortic occlusion is time-limited given the ischemia-reperfusion injury generated. Significant effort has been put into translational research to develop new strategies to alleviate the ischemia-reperfusion injury and extend the application of endoaortic occlusion. Targeted regional optimization (TRO) is a partial REBOA strategy to augment proximal aortic and cerebral blood flow while targeting minimal threshold of distal perfusion beyond the zone of partial aortic occlusion. The objective of TRO is to reduce the degree of ischemia caused by complete aortic occlusion while providing control of distal hemorrhage. This review provides a synopsis of the concept of TRO, pre-clinical, translational experiences with TRO and early clinical outcomes. Early results from TRO strategies are promising; however, further studies are needed prior to large-scale implementation into clinical practice.

End-tidal Carbon Dioxide as an Indicator of Partial REBOA and Distal Organ Metabolism in Normovolemia and Hemorrhagic Shock in Anesthetized Pigs

INTRODUCTION

It is difficult to estimate the ischemic consequences when using partial resuscitative endovascular balloon occlusion of the aorta (REBOA). The aim was to investigate if end-tidal carbon dioxide (ETCO2) is correlated to degree of aortic occlusion, measured as distal aortic blood flow, and distal organ metabolism, estimated as systemic oxygen consumption (VO2), in a porcine model of normovolemia and hemorrhagic shock.

MATERIALS AND METHODS

Nine anesthetized pigs (25-32 kg) were subjected to incremental steps of zone 1 aortic occlusion (reducing distal aortic blood flow by 33%, 66%, and 100%) during normovolemia and hemorrhagic grade IV shock. Hemodynamic and respiratory variables, and blood samples, were measured. Systemic VO2 was correlated to ETCO2 and measures of partial occlusion previously described.

RESULTS

Aortic occlusion gradually lowered distal blood flow and pressure, whereas ETCO2, VO2 and carbon dioxide production decreased at 66% and 100% aortic occlusion. Aortic blood flow correlated significantly to ETCO2 during both normovolemia and hemorrhage (R = 0.84 and 0.83, respectively) and to femoral mean pressure (R = 0.92 and 0.83, respectively). Systemic VO2 correlated strongly to ETCO2 during both normovolemia and hemorrhage (R = 0.91 and 0.79, respectively), blood flow of the superior mesenteric artery (R = 0.77 and 0.85, respectively) and abdominal aorta (R = 0.78 and 0.78, respectively), but less to femoral blood pressure (R = 0.71 and 0.54, respectively).

CONCLUSION

ETCO2 was correlated to distal aortic blood flow and VO2 during incremental degrees of aortic occlusion thereby potentially reflecting the degree of aortic occlusion and the ischemic consequences of partial REBOA. Further studies of ETCO2, and potential confounders, in partial REBOA are needed before clinical use.

A survey of resuscitative endovascular balloon occlusion of the aorta (REBOA) program implementation in Canadian trauma centres

OBJECTIVE

To determine how many Level 1 and Level 2 trauma centres in Canada have implemented a resuscitative endovascular balloon occlusion of the aorta (REBOA) program, and to identify facilitators and barriers to successful implementation of REBOA programs.

METHODS

An electronic survey was developed and administered in November 2019 (updated in July 2021) via email to directors at all 32 Level 1 and Level 2 trauma centres across Canada, and to the medical director in PEI (no Level 1 or Level 2 capacity). Survey responses were supplemented by an online search in PubMed and the grey literature. Responses were analyzed using simple descriptive statistics including frequencies and proportions.

RESULTS

We received responses from directors at 22 sites (17 Level 1 trauma centres, 4 Level 2 trauma centres, PEI) for a response rate of 66.7%. There are 6 Level 1 trauma centres with REBOA programs; all were implemented between 2017 and 2019. One additional Level 1 trauma centre that did not respond was found to have a REBOA program; thus, 21.9% (7/32) of Canadian Level 1 and Level 2 trauma centres have an existing REBOA program. These programs are located in three provinces (British Columbia, Ontario, Quebec). Five other centres are planning on implementing a REBOA program in the next 2 years. The number of REBOA cases performed ranged from 0 to 30 (median 2). Factors contributing most to successful program implementation were having physician champions and patient populations with sufficient REBOA candidates, while cost and lack of expertise were the greatest barriers identified.

CONCLUSION

As of July 2021, 21.9% (7/32) of Canadian Level 1 and Level 2 trauma centres have a REBOA program. Physician champions and a patient population with sufficient numbers of REBOA candidates were the most important factors contributing to successful implementation of these programs.

Quantifying the need for pediatric REBOA: A gap analysis

BACKGROUND

Trauma is the leading cause of death in children. Resuscitative endovascular balloon occlusion of the aorta (REBOA) provides temporary hemorrhage control, but its potential benefit has not been assessed in children. We hypothesized that there are pediatric patients who may benefit from REBOA.

METHODS

Trauma patients <18 years old at a level 1 pediatric trauma center between 2009 and 2019 were queried for deaths, pre-hospital cardiac arrest, massive transfusion protocol activation, transfusion requirement, or hemorrhage control surgery. These patients defined the cohort of severely injured patients. From this cohort, patients with intraabdominal injuries for which REBOA may provide temporary hemorrhage control were identified, including solid organ injury necessitating intervention, vascular injury, or pelvic hemorrhage.

RESULTS

There were 239 severely injured patients out of 6538 pediatric traumas. Of these, 38 had REBOA-amenable injuries (15.9%) with 34.2% mortality, accounting for 10.2% of all pediatric trauma deaths at one center. Eleven patients with REBOA-amenable injuries had TBI (28.9%). Patients with REBOA-amenable injuries represented 0.6% of all pediatric traumas.

CONCLUSION

Nearly 20% of severely injured pediatric patients could potentially benefit from REBOA. The overall proportion of pediatric patients with REBOA-amenable injuries is similar to adult studies.

TYPE OF STUDY

Retrospective comparative study.

LEVEL OF EVIDENCE

Level III.

Assessment of mechanical and biocompatible performance of ultra-large nitinol endovascular devices fabricated via a low-energy laser joining process

Nitinol is an excellent candidate material for developing various self-expanding endovascular devices due to its unique properties such as superelasticity, biocompatibility and shape memory effect. A low-energy laser joining technique suggests a high potential to create various large diameter Nitinol endovascular devices that contain complex geometries. The primary purpose of the study is to investigate the effects of laser joining process parameters with regard to the mechanical and biocompatible performance of Nitinol stents. Both the chemical composition and the microstructure of the laser-welded joints were evaluated using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). In vitro study results on cytotoxicity demonstrated that the joining condition of 8 Hz frequency and 1 kW laser power showed the highest degree of endothelial cell viability after thermal annealing in 500°C for 30 min. Also, in vitro study results showed the highest oxygen content at 0.9 kW laser power, 8 Hz frequency, and 0.3 mm spot size after the thermal annealing. Mechanical performance test results showed that the optimal condition for the highest disconnecting force was found at 1 Hz frequency and 1 kW power with 0.6 mm spot size. Two new endovascular devices have been fabricated using the optimized laser joining parameters, which have demonstrated successful device delivery and retrieval, as well as acute biocompatibility.

Resuscitative endovascular balloon occlusion of the aorta in combat casualties: The past, present, and future

BACKGROUND

Noncompressible torso hemorrhage is a leading cause of preventable death on the battlefield. Intra-aortic balloon occlusion was first used in combat in the 1950s, but military use was rare before Operation Iraqi Freedom and Operation Enduring Freedom. During these wars, the combination of an increasing number of deployed vascular surgeons and a significant rise in deaths from hemorrhage resulted in novel adaptations of resuscitative endovascular balloon occlusion of the aorta (REBOA) technology, increasing its potential application in combat. We describe the background of REBOA development in response to a need for minimally invasive intervention for hemorrhage control and provide a detailed review of all published cases (n = 47) of REBOA use for combat casualties. The current limitations of REBOA are described, including distal ischemia and reperfusion injury, as well as ongoing research efforts to adapt REBOA for prolonged use in the austere setting.

LEVEL OF EVIDENCE

Level V.

Computed tomography imaging of resuscitative endovascular balloon occlusion of the aorta (REBOA): pearls and pitfalls

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is performed in patients with hemorrhagic shock who develop massive subdiaphragmatic bleeding. This procedure enables rapid and less invasive aortic blockade compared to resuscitative thoracotomy and aortic cross-clamp procedures. However, the REBOA procedure is often blindly performed in the emergency department without fluoroscopy, and the appropriateness of the procedure may be evaluated on computed tomography (CT) after REBOA. Therefore, radiologists should be familiar with the imaging features of REBOA. We present a pictorial review of the radiological findings of REBOA along with a description of the procedure, its complications, and pitfalls.

A Life Saving Emergency Department Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) with Open Groin Technique

A 53-year-old male pedestrian was hit by a car and arrived at our hospital with a blunt abdominal injury and hemorrhagic shock. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) was performed in a timely fashion using the open groin technique in the emergency room. The procedure resulted in rapid improvement of hemodynamic status while the bleeding source was controlled. Recently, REBOA is a proper adjunctive procedure in major non-compressible torso hemorrhage patients. The procedure requires a portable X-ray or fluoroscopic machine in the ER to confirm the balloon’s position. This method has likely limited the use of REBOA in developing countries. The procedure with open groin technique, using anatomical landmarks and physiologic change to confirm the position of the balloon, has been developed to address these concerns. Here we report on the treatment’s success with this technique and believe that it can benefit trauma patient care.

American Association for the Surgery of Trauma-World Society of Emergency Surgery guidelines on diagnosis and management of abdominal vascular injuries

Abdominal vascular trauma accounts for a small percentage of military and a moderate percentage of civilian trauma, affecting all age ranges and impacting young adult men most frequently. Penetrating causes are more frequent than blunt in adults, while blunt mechanisms are more common among pediatric populations. High rates of associated injuries, bleeding, and hemorrhagic shock ensure that, despite advances in both diagnostic and therapeutic technologies, immediate open surgical repair remains the mainstay of treatment for traumatic abdominal vascular injuries. Because of their devastating nature, abdominal vascular injuries remain a significant source of morbidity and mortality among trauma patients. The American Association for the Surgery of Trauma in conjunction with the World Society of Emergency Surgery seek to summarize the literature to date and provide guidelines on the presentation, diagnosis, and treatment of abdominal vascular injuries. LEVEL OF EVIDENCE: Review study, level IV.

Open versus endovascular REBOA control of blood loss during cesarean delivery in the placenta accreta spectrum: A single-center retrospective case control study

OBJECTIVE

The aim of this study was to compare two vascular control options for blood loss prevention and hysterectomy during cesarean delivery (CD2): endovascular balloon occlusion of the aorta (REBOA3) and open bilateral common iliac artery occlusion (CIAO4) in women with extensive placenta accreta spectrum (PAS5).

STUDY DESIGN

This was retrospective comparison of cases of PAS using either CIAO (October 2017 through October 2018) or REBOA (November 2018 through November 2019) to prevent pathologic hemorrhage during scheduled CD. Women with confirmed placenta increta/percreta underwent either CD then intraoperative post-delivery, pre-hysterectomy open vascular control of both CIA6 (CIAO group) or pre-operative, ultrasound-guided, fluoroscopy-free REBOA followed by standard CD and balloon inflation after fetal delivery (REBOA group). Intraoperative blood loss, transfusion volumes, surgical time, blood pressure, maternal and neonatal outcomes, hospitalization length and postoperative complications were compared.

RESULTS

The REBOA and CIAO groups included 12 and 16 women, respectively, with similar median age of 35 years and gestational age of 34-35 weeks. All REBOA catheters were successfully placed into aortic zone three under ultrasound guidance. The quantitated median intraoperative blood loss was significantly lower for the REBOA group, (541 [IQR 300-750] mL) compared to the CIAO group (3331 [IQR 1150-4750] mL (P = 0.001). As a result, the total volume of fluid and blood replacement therapy was significantly lower in the REBOA group (P < 0.05). Median surgical time in the REBOA group was less than half as long: 76 [IQR 64-89] minutes compared to 168 [IQR 90-222] minutes in the CIAO group (P = 0.001). None of the women with REBOA required hysterectomy, while 8/16 women in the CIAO group did (P = 0.008). Furthermore, the post-anesthesia recovery and hospital discharge times in the REBOA-group were shorter (P < 0.05). One thromboembolic complication occurred in each group. The only REBOA-associated complication was non-occlusive femoral artery thrombosis, with no surgical management required. No maternal or neonatal deaths occurred in either group.

CONCLUSION

Fluoroscopy-free REBOA for women with PAS is associated with improved vascular control, perioperative blood loss, the need for transfusion and hysterectomy and reduces surgical time when compared to bilateral CIAO.

Resuscitative Endovascular Balloon Occlusion of Aorta: A Systematic Review

BACKGROUND

The data on resuscitative endovascular balloon occlusion of the aorta (REBOA) use continue to grow with its increasing use in trauma centers. The data in her last 5 years have not been systematically reviewed. We aim to assess current literature related to REBOA use and outcomes among civilian trauma populations.

METHODS

A literature search using PubMed, EMBASE, and JAMA Network for studies regarding REBOA usage in civilian trauma from 2016 to 2020 is carried out. This review followed preferred reporting items for systematic reviews and meta-analysis guidelines.

RESULTS

Our search yielded 35 studies for inclusion in our systematic review, involving 4073 patients. The most common indication for REBOA was patient presentation in hemorrhagic shock secondary to traumatic injury. REBOA was associated with significant systolic blood pressure improvement. Of 4 studies comparing REBOA to non-REBOA controls, 2 found significant mortality benefit with REBOA. Significant mortality improvement with REBOA compared to open aortic occlusion was seen in 4 studies. In the few studies investigating zone placement, highest survival rate was seen in patients undergoing zone 3. Overall, reports of complications directly related to overall REBOA use were relatively low.

CONCLUSION

REBOA has been shown to be effective in promoting hemodynamic stability in civilian trauma. Mortality data on REBOA use are conflicting, but most studies investigating REBOA vs. open occlusion methods suggest a significant survival advantage. Recent data on the REBOA technique (zone placement and partial REBOA) are sparse and currently insufficient to determine advantage with any particular variation. Overall, larger prospective civilian trauma studies are needed to better understand the benefits of REBOA in high-mortality civilian trauma populations.

STUDY TYPE

Systematic Review.

LEVEL OF EVIDENCE

III- Therapeutic.

Practical tips for performing resuscitative endovascular balloon occlusion of the aorta

Background:

Hemorrhage is the leading cause of death in trauma settings. Non-compressible torso hemorrhage, which is caused by abdominopelvic and thoracic injuries, is an important cause of subsequent organ dysfunction and poor outcomes in multiple trauma patients. The management of hemodynamically unstable patients with non-compressible torso hemorrhage has changed, and the concept of damage control resuscitation has been developed in the last decades. Currently, resuscitative endovascular balloon occlusion of the aorta (REBOA) as a method of temporary stabilization is the modern evolution of bleeding control, and it is in the middle of a paradigm shift as a treatment for non-compressible torso hemorrhage. Despite its effectiveness in patients with hemorrhagic shock, the application of REBOA remains limited because of lack of experience and troubleshooting guidelines.

Objectives:

The aim of study was to provide useful tips for the implementing a step-by-step procedure for REBOA in various hospital settings and capabilities.

Methods:

We introduced REBOA procedures using a REBOA-customized 7 Fr balloon catheter through the animation models or radiography from preparation to access, catheter management, and device removal after procedure completed.

Results:

We have described REBOA procedures as follows: identification of the common femoral artery, arterial access for placement of a guidewire, precautions during a sheath insertion, guidewire and balloon positioning in the aorta, occlusion zones and adjustment of balloon location, REBOA strategy for extending the occlusion time, balloon deflation and removal, sheath removal, and medical records.

Conclusion:

We believe that the practical tips mentioned in this article will help in performing the REBOA procedure systematically and developing an effective REBOA framework.

Partial Resuscitative Endovascular Balloon Occlusion of the Aorta: A Systematic Review of the Preclinical and Clinical Literature

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has become a standard adjunct for the management of life-threatening truncal hemorrhage, but the technique is limited by the sequalae of ischemia distal to occlusion. Partial REBOA addresses this limitation, and the recent Food and Drug Administration approval of a device designed to enable partial REBOA will broaden its application. We conducted a systematic review of the available animal and clinical literature on the methods, impacts, and outcomes associated with partial REBOA as a technique to enable targeted proximal perfusion and limit distal ischemic injury. We hypothesize that a systematic review of the published animal and human literature on partial REBOA will provide actionable insight for the use of partial REBOA in the context of future wider clinical implementation of this technique.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Protocols guidelines, we conducted a search of the available literature which used partial inflation of a REBOA balloon catheter. Findings from 22 large animal studies and 14 clinical studies met inclusion criteria.

RESULTS

Animal and clinical results support the benefits of partial REBOA including extending the resuscitative window extended safe occlusion time, improved survival, reduced proximal hypertension, and reduced resuscitation requirements. Clinical studies provide practical physiologic targets for partial REBOA including a period of total occlusion followed by gradual balloon deflation to achieve a target proximal pressure and/or target distal pressure.

CONCLUSIONS

Partial REBOA has several benefits which have been observed in animal and clinical studies, most notably reduced ischemic insult to tissues distal to occlusion and improved outcomes compared with total occlusion. Practical clinical protocols are available for the implementation of partial REBOA in cases of life-threatening torso hemorrhage.

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.

Low profile REBOA device for increasing systolic blood pressure in hemodynamic instability: single-center 4-year experience of use of ER-REBOA

Background

Hemodynamic instability due to torso hemorrhage can be managed with the assistance of resuscitative endovascular balloon occlusion of the aorta (REBOA). This is a report of a single-center experience using the ER-REBOA™ catheter for traumatic and non-traumatic cases as an adjunct to hemorrhage control and as part of the EndoVascular resuscitation and Trauma Management (EVTM) concept. The objective of this report is to describe the clinical usage, technical success, results, complications and outcomes of the ER-REBOA™ catheter at Örebro University hospital, a middle-sized university hospital in Europe.

Methods

Data concerning patients receiving the ER-REBOA™ catheter for any type of hemorrhagic shock and hemodynamic instability at Örebro University hospital in Sweden were collected prospectively from October 2015 to May 2020.

Results

A total of 24 patients received the ER-REBOA™ catheter (with the intention to use) for traumatic and non-traumatic hemodynamic control; it was used in 22 patients. REBOA was performed or supervised by vascular surgeons using 7–8 Fr sheaths with an anatomic landmark or ultrasound guidance. Systolic blood pressure (SBP) increased significantly from 50 mmHg (0–63) to 95 mmHg (70–121) post REBOA. In this cohort, distal embolization and balloon rupture due to atherosclerosis were reported in one patient and two patients developed renal failure. There were no cases of balloon migration. Overall 30-day survival was 59%, with 45% for trauma patients and 73% for non-traumatic patients. Responders to REBOA had a significantly lower rate of mortality at both 24 h and 30 days.

Conclusions

Our clinical data and experience show that the ER-REBOA™ catheter can be used for control of hemodynamic instability and to significantly increase SBP in both traumatic and non-traumatic cases, with relatively few complications. Responders to REBOA have a significantly lower rate of mortality.

Size matters: first-in-human study of a novel 4 French REBOA device

Background

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emerging technique used for non-compressible torso hemorrhage. However, its current use continues to be limited and there is a need for a simple, fast, and low profile REBOA device. Our objective was to evaluate the feasibility of a novel 4 French REBOA device called the COBRA-OS (Control of Bleeding, Resuscitation, Arterial Occlusion System).

Methods

This study is the first-in-human feasibility trial of the COBRA-OS. Due to the difficulty of trialing the device in the trauma setting, we performed a feasibility study using organ donors (due to the potential usefulness of the COBRA-OS for normothermic regional perfusion) after neurological determination of death (NDD) prior to organ retrieval. Bilateral 4 French introducer sheaths were placed in both femoral arteries and the COBRA-OS was advanced up the right side and deployed in the thoracic aorta (Zone 1). Once aortic occlusion was confirmed via the left-sided arterial line, the device was deflated, moved to the infrarenal aorta (Zone 3), and redeployed.

Results

A total of 7 NDD organ donors were entered into the study, 71% men, with a mean age 46.6 years (range 26 to 64). The COBRA-OS was able to occlude the aorta in Zones 1 and 3 in all patients. The mean time of placing a 4 French sheath was 47.7 seconds (n=13, range 28 to 66 seconds). The mean time from skin to Zone 1 aortic occlusion was 70.1 seconds (range 58 to 105 seconds); mean balloon volumes were 15 mL for Zone 1 (range 13 to 20 mL) and 9 mL for Zone 3 (range 6 to 15 mL); there were no complications and visual inspection of the aorta in all patients revealed no injury.

Discussion

The COBRA-OS is a novel 4 French REBOA device that has demonstrated fast and safe aortic occlusion in this first-in-human feasibility study.

Level of evidence

Level V, therapeutic.

Use of bilobed partial resuscitative endovascular balloon occlusion of the aorta is logistically superior in prolonged management of a highly lethal aortic injury

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a viable technique for management of noncompressible torso hemorrhage. The major limitation of the current unilobed fully occlusive REBOA catheters is below-the-balloon ischemia-reperfusion complications. We hypothesized that partial aortic occlusion with a novel bilobed partial (p)REBOA-PRO would result in the need for less intraaortic balloon adjustments to maintain a distal goal perfusion pressure as compared with currently available unilobed ER-REBOA.

METHODS

Anesthetized (40-50 kg) swine randomized to control (no intervention), ER-REBOA, or pREBOA-PRO underwent supraceliac aortic injury. The REBOA groups underwent catheter placement into zone 1 with initial balloon inflation to full occlusion for 10 minutes followed by gradual deflation to achieve and subsequently maintain half of the baseline below-the-balloon mean arterial pressure (MAP). Physiologic data and blood samples were collected at baseline and then hourly. At 4 hours, the animals were euthanized, total blood loss and urine output were recorded, and tissue samples were collected.

RESULTS

Baseline physiologic data and basic laboratories were similar between groups. Compared with control, interventions similarly prolonged survival from a median of 18 minutes to over 240 minutes with comparable mortality trends. Blood loss was similar between partial ER-REBOA (41%) and pREBOA-PRO (51%). Partial pREBOA-PRO required a significantly lower number of intraaortic balloon adjustments (10 ER-REBOA vs. 3 pREBOA-PRO, p < 0.05) to maintain the target below-the-balloon MAP. The partial ER-REBOA group developed significantly increased hypercapnia, fibrin clot formation on TEG, liver inflammation, and IL-10 expression compared with pREBOA-PRO.

CONCLUSION

In this highly lethal aortic injury model, use of bilobed pREBOA-PRO for a 4-hour partial aortic occlusion was logistically superior to unilobed ER-REBOA. It required less intraaortic balloon adjustments to maintain target MAP and resulted in less inflammation.

A feasibility study of partial REBOA data in a high-volume trauma center

PURPOSE

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is used to temporize patients with infradiaphragmatic hemorrhage. Current guidelines advise < 30 min, to avoid ischemia/ reperfusion injury, whenever possible. The technique of partial REBOA (P-REBOA) has been developed to minimize the effects of distal ischemia. This study presents our clinical experience with P-REBOA, comparing outcomes to complete occlusion (C-REBOA).

PATIENTS AND METHODS

Retrospective analysis of patients' electronic data and local REBOA registry between January 2016 and May 2019.

INCLUSION CRITERIA

adult trauma patients who received Zone I C-REBOA or P-REBOA for infradiaphragmatic hemorrhage, who underwent attempted exploration in the operating room. Comparison of outcomes based on REBOA technique (P-REBOA vs C-REBOA) and occlusion time (> 30 min, vs ≤ 30 min) RESULTS: 46 patients were included, with 14 treated with P-REBOA. There were no demographic differences between P-REBOA and C-REBOA. Prolonged (> 30 min) REBOA (regardless of type of occlusion) was associated with increased mortality (32% vs 0%, p = 0.044) and organ failure. When comparing prolonged P-REBOA with C-REBOA, there was a trend toward lower ventilator days [19 (11) vs 6 (9); p = 0.483] and dialysis (36.4% vs 16.7%; p = 0.228) with significantly less vasopressor requirement (72.7% vs 33.3%; p = 0.026).

CONCLUSION

P-REBOA can be delivered in a clinical setting, but is not currently associated with improved survival in prolonged occlusion. In survivors, there is a trend toward lower organ support needs, suggesting that the technique might help to mitigate ischemic organ injury. More clinical data are needed to clarify the benefit of partial occlusion REBOA.

Regenerative rehabilitation of catastrophic extremity injury in military conflicts and a review of recent developmental efforts

AIM OF THE REVIEW

This review aims to describe the current state of regenerative rehabilitation of severe military extremity injuries, and promising new therapies on the horizon.

DISCUSSION

The nature of warfare is rapidly shifting with information operations, autonomous weapons, and the threat of full-scale peer adversary conflicts threatening to create contested environments with delayed medical evacuation to definitive care. More destructive weapons will lead to more devastating injuries, creating new challenges for limb repair and restoration. Current paradigms of delayed rehabilitation following initial stabilization, damage control surgery, and prolonged antibiotic therapy will need to shift. Advances in regenerative medicine technologies offer the possibility of treatment along the continuum of care. Regenerative rehabilitation will begin at the point of injury and require a holistic, organ-systems approach.

CONCLUSIONS

Both technological improvements and a rapidly advancing understanding of injury pathophysiology will contribute to improved limb-salvage outcomes, and shift the calculus away from early limb amputation.

Partial Resuscitative Endovascular Balloon Occlusion of the Aorta via the Tri-Lobe Balloon Catheter

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) provides a minimally invasive alternative to resuscitative thoracotomy. The high morbidity associated with prolonged aortic occlusion has given rise to the concept of partial REBOA (pREBOA). We evaluated the novel use of the GORE Tri-Lobe Balloon Catheter (GORE) as a functional pREBOA catheter and compared it with existing REBOA and pREBOA techniques in a porcine hemorrhagic shock model.

MATERIALS AND METHODS

Fifteen male Yorkshire swine were subjected to hemorrhagic shock with zone 1 aortic occlusion via standard REBOA techniques or a partial occlusion approach using a prototype pREBOA or GORE catheter. Continuous invasive monitoring was performed and laboratory values were analyzed every 30 min.

RESULTS

One animal from the GORE cohort was excluded because of early demise from nonstudy factors. Survival to 120 mins was comparable between all study groups: REBOA resulting in 40% survival, pREBOA 60%, and Gore 50% (P = 0.685). No differences in lactate, base deficit, and pH between the cohorts were demonstrated at all measured time points; however, trends toward more physiologic values were appreciated in the GORE and pREBOA cohorts. Urine output was significantly improved during the course of the study in the GORE cohort (8.77 mL/kg) versus REBOA (5.46 mL/kg) and pREBOA (4.48 mL/kg) (P = 0.001).

CONCLUSIONS

The GORE Tri-Lobe Balloon Catheter represents a potentially viable and commercially available alternative device for pREBOA that may achieve survivable hemorrhage control while preventing lethal reperfusion injury. Further studies should be performed after instrument refinement with larger study populations to confirm this potential.

Effects of Extended Lower Extremity Cooling Following Zone 3 REBOA in a Porcine Hemorrhage Model

INTRODUCTION

External cooling of ischemic limbs has been shown to have a significant protective benefit for durations up to 4 hours.

MATERIALS AND METHODS

It was hypothesized that this benefit could be extended to 8 hours. Six swine were anesthetized and instrumented, then underwent a 25% total blood volume hemorrhage. Animals were randomized to hypothermia or normothermia followed by 8 hours of Zone 3 resuscitative endovascular balloon occlusion of the aorta, then resuscitation with shed blood, warming, and 3 hours of critical care. Physiologic parameters were continuously recorded, and laboratory specimens were obtained at regular intervals.

RESULTS

There were no significant differences between groups at baseline. There were no significant differences between creatine kinase in the hypothermia group when compared to the normothermia group (median [IQR] = 15,206 U/mL [12,476-19,987] vs 23,027 U/mL [18,745-26,843]); P = 0.13) at the end of the study. Similarly, serum myoglobin was also not significantly different in the hypothermia group after 8 hours (7,345 ng/mL [5,082-10,732] vs 5,126 ng/mL [4,720-5,298]; P = 0.28). No histologic differences were observed in hind limb skeletal muscle.

CONCLUSION

While external cooling during prolonged Zone 3 resuscitative endovascular balloon occlusion of the aorta appears to decrease ischemic muscle injury, this benefit appears to be time dependent. As the ischemic time approaches 8 hours, the benefit from hypothermia decreases.