REBOARREST, resuscitative endovascular balloon occlusion of the aorta in non-traumatic out-of-hospital cardiac arrest: a study protocol for a randomised, parallel group, clinical multicentre trial

Resuscitative Endovascular Balloon Occlusion of the Aorta in surgical and trauma patients: a systematic review, meta-analysis and practice management guideline from the Eastern Association for the Surgery of Trauma

Background

The role of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) in the management of patients with subdiaphragmatic bleeding, as well as its utility in traumatic cardiac arrest (TCA), is unknown.

Methods

A working group from the Eastern Association for the Surgery of Trauma (EAST) applied the Grading of Recommendations Assessment, Development and Evaluation methodology (GRADE) to perform a systematic review and meta-analysis, assess the level of evidence, and create recommendations pertaining to the use of REBOA in the management of trauma or non-trauma patients, as well as those in TCA (1946 to 2024).

Results

Thirty-one studies were included in the meta-analysis. In unstable trauma patients with subdiaphragmatic bleeding, there was no significant difference in mortality among patients who were treated with REBOA vs no REBOA [OR 0.86, 95% CI 0.37, 2.04]. Subgroup analysis for individuals with pelvic fractures demonstrated higher mortality for REBOA vs no REBOA [OR=2.15, CI 1.35, 3.42]. In patients with TCA, pooled analysis demonstrated decreased mortality with REBOA vs resuscitative thoracotomy (OR 0.32, 95% CI 0.15, 0.69). Compared with no REBOA, prophylactic placement of REBOA prior to cesarean section in placenta accreta syndrome (PAS) had lower intra-operative blood loss [-1.06 L, CI -1.57 to -0.56] and red blood cell transfusion [-2.44 units, CI -4.27 to -0.62]. Overall, the level of evidence was assessed by the working group as very low.

Conclusion

Considering the risks associated with its use and lack of discernible benefit, the committee conditionally recommends against the use of REBOA in trauma patients who are hemodynamically unstable due to suspected subdiaphragmatic hemorrhage. Further research is needed to identify specific subpopulations who may benefit. For individuals with TCA due to suspected subdiaphragmatic bleeding and for prophylactic placement in PAS, the committee conditionally recommends for the use of REBOA.

Level of Evidence

IV.

Resuscitative Endovascular Balloon Occlusion of the Aorta: What You Need to Know

ABSTRACT

Hemorrhage remains one of the leading causes of death from traumatic injury in both the civilian and military populations. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a minimally invasive technique that can be used to treat hemorrhage in the critically ill. An alternative to maximally invasive methods such as resuscitative thoracotomy, REBOA is a temporizing measure to prevent exsanguination and allow for transition to definitive hemorrhage control. It is easily deployed by trained users and does not require surgical expertise to place. Its use has increased over the past decade with a growing body of literature that suggests it improves outcomes in select hemorrhagic trauma patients compared with patients who do not receive REBOA. REBOA has also been used for select nontraumatic cases. Judicious patient selection, knowing the technical aspects of placing REBOA, and clarity regarding its indications are key to maximize its efficacy as a mitigatory tool in hemorrhagic shock. This "What You Need To Know" review presents current evidence regarding use of REBOA for the acute care surgeon.

LEVEL OF EVIDENCE

Level V.

Balloon occlusion of the aorta during cardiac arrest -a death blow to the intestines?

BACKGROUND

The use of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) in non-traumatic cardiac arrest may result in worsened intestinal ischaemia. What are the consequences?

MAIN TEXT

Human data on REBOA in non-traumatic cardiac arrest is limited. In general, cardiac output is reduced during resuscitation, and mesenteric blood flow may be further reduced by intravenous adrenaline (epinephrine). Balloon occlusion of the thoracic aorta will potentially lead to a complete cessation of intestinal blood flow. Experimental studies demonstrate that intestinal damage increases with REBOA inflation time, and that 45-60 min of ischaemia may result in irreversible damage. However, it is unclear when intestinal ischaemia starts to affect patient-oriented outcomes. A barrier for assessing the consequences of intestinal ischemia is that it is a challenge to diagnose. A biomarker for intestinal injury, Intestinal Fatty Acid Binding Protein (IFABP), was elevated in all cardiac arrest patients and had a striking association with mortality in one study. In another study, all patients with intestinal ischemia diagnosed on CT died. However, intestinal ischemia could be a marker of whole-body ischemia and not an independent contributor to poor outcome. The clinical importance of worsened intestinal ischemia by REBOA during cardiac arrest is not established.

CONCLUSION

The impact of intestinal ischaemia following cardiac arrest is uncertain, but ischaemia is likely to be exacerbated by REBOA. However, inflation of the balloon will occur when the patient is still in cardiac arrest and is a means to achieve ROSC. Hence, we argue that the added intestinal ischaemia caused by REBOA may be of limited clinical importance, but this is still to be answered.

Intra-aortic balloon pump synchronized with chest compressions improves outcome during cardiopulmonary resuscitation in experimental cardiac arrest

BACKGROUND

Intra-aortic balloon pump (IABP) and resuscitative endovascular balloon occlusion of the aorta (REBOA) are two endovascular intervention methods for circulatory support. The aim of this study was to compare the hemodynamic effects of simultaneous mechanical chest compressions (MCC) with IABP, REBOA and those with only MCC (overall and detailed in the MCC cycle) and return of spontaneous circulation (ROSC) during cardiopulmonary resuscitation (CPR) in experimental non-traumatic cardiac arrests (CA).

METHOD

CA was electrically induced (ventricular fibrillation) in 24 anesthetized pigs, which then were randomized to MCC synchronized IABP (n = 8), total occluded REBOA (n = 8), or control (n = 8). After 10 min of CA, CPR with MCC was started followed by one of the interventions after one minute of CPR. Every other minute after MCC start, the pigs were defibrillated with 200 J if VF/ventricular tachycardia, and after six minutes, adrenaline was administered and repeated every four minutes. The proportions of ROSC were calculated. Hemodynamic variables, including systemic blood and coronary perfusion pressures (CPP), and carotid and iliac blood flows, were collected and analyzed with 0.02 s resolution.

RESULTS

In both the IABP and REBOA groups, 7 of 8 animals (87.5 %) achieved ROSC, in contrast with 2 of 8 (25 %) in the control group (P = 0.04). IABP and REBOA significantly increased systemic arterial pressure (P = 0.002 and P = 0.015, respectively), and REBOA also increased CPP and carotid blood flow when compared to controls (P = 0.007 and P = 0.03, respectively). Animals with IABP had a preserved blood flow in the iliac artery during CPR. No differences were detected after ROSC in hemodynamic, metabolic, and organ injury variables between the REBOA and IABP groups.

CONCLUSION

Both IABP and REBOA increased the proportion of ROSC compared to controls. However, REBOA occluded distal blood flow, while IABP maintained it. This study suggests that MCC synchronized IABP could be an adjunct in the treatment of non-traumatic CA.

A protocol for the ERICA-ARREST feasibility study of Emergency Resuscitative Endovascular Balloon occlusion of the Aorta in Out-of-Hospital Cardiac Arrest

Background

Fewer than one in ten out-of-hospital cardiac arrest (OHCA) patients survive to hospital discharge in the UK. For prehospital teams to improve outcomes in patients who remain in refractory OHCA despite advanced life support (ALS); novel strategies that increase the likelihood of return of spontaneous circulation, whilst preserving cerebral circulation, should be investigated. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) has been shown to improve coronary and cerebral perfusion during cardiopulmonary resuscitation. Early, prehospital initiation of REBOA may improve outcomes in patients who do not respond to standard ALS. However, there are significant clinical, technical, and logistical challenges with rapidly delivering prehospital REBOA in OHCA; and the feasibility of delivering this intervention in the UK urban-rural setting has not been evaluated.

Methods

The Emergency Resuscitative Endovascular Balloon Occlusion of the Aorta in Out-of-Hospital Cardiac Arrest (ERICA-ARREST) study is a prospective, single-arm, interventional feasibility study. The trial will enrol 20 adult patients with non-traumatic OHCA. The primary objective is to assess the feasibility of performing Zone I (supra-coeliac) aortic occlusion in patients who remain in OHCA despite standard ALS in the UK prehospital setting. The trial's secondary objectives are to describe the hemodynamic and physiological responses to aortic occlusion; to report key time intervals; and to document adverse events when performing REBOA in this context.

Discussion

Using compressed geography, and targeted dispatch, alongside a well-established femoral arterial access programme, the ERICA-ARREST study will assess the feasibility of deploying REBOA in OHCA in a mixed UK urban and rural setting.Trial registration.ClinicalTrials.gov (NCT06071910), registration date October 10, 2023, https://classic.clinicaltrials.gov/ct2/show/NCT06071910.

Feasibility of a 4 French resuscitative endovascular balloon occlusion of the aorta (REBOA) device for nontraumatic cardiac arrest in a randomized controlled study using a large porcine model

Aim

The objectives of this study were to assess the return of spontaneous circulation rates and hemodynamic response of large swine (>65Kg) during cardiopulmonary resuscitation after nontraumatic cardiac arrest using the COBRA-OS® aortic occlusion balloon and to address limitations of large swine closed-chest cardiopulmonary resuscitation by comparing closed-chest vs. open-chest cardiopulmonary resuscitation.

Methods

Yorkshire pigs (n = 10) weighing >65 kg were anesthetized and ventilated. After 7 min of untreated ventricular fibrillation (VF), animals were randomized to receive mechanical closed-chest cardiopulmonary resuscitation or open-chest cardiac massage. Following a 5-minute low-flow state, advanced cardiac life support algorithms were started and the COBRA-OS® was inflated in the thoracic aorta. Animals that achieved return of spontaneous circulation were re-started on mechanical ventilation and medications, CPR, defibrillation, and aortic occlusion were discontinued. The primary outcome was return of spontaneous circulation and secondary outcomes were mean arterial pressures generated in the low flow and aortic occlusion states before return of spontaneous circulation. Groups were compared with a t-test or Mann-Whitney U test for normal and non-parametric data, respectively, while categorical data was compared with the chi square test.

Results

Return of spontaneous circulation was obtained in 4 animals (80%) in the open cardiac massage group and none in the mechanical closed-chest CPR group (p < 0.05). The COBRA-OS® successfully occluded all aortas and animals experienced higher mean arterial pressures in both groups with aortic occlusion (median 15 mm Hg, IQR 13-23 mm Hg), but with a higher MAP difference in the open cardiac massage group (-12.2 mm Hg, [-2.581, -21.819]).

Conclusions

Consideration should be given to intra-thoracic cardiac massage to increase cardiopulmonary resuscitation effectiveness and therefore return of spontaneous circulation rates in large (>65 kg) swine models of nontraumatic cardiac arrest. The COBRA-OS® demonstrated feasibility for use in this model.The Keenan Research Center, Li Ka Shing Knowledge Institute of St. Michael's Hospital Animal Care Committee: ACC Protocol #726.

Ultrasound guided arterial access for combat medics: A blinded proof-of-concept study using echogenic needles

BACKGROUND

Obtaining percutaneous vascular access in hemodynamically unstable patients with constricted vessels can be challenging. Training combat medics in this procedure is necessary for administration of fluid and blood products and introducing endovascular bleeding control tools in pre-hospital settings. Echogenic coated needles might provide better ultrasound visibility in invasive procedures and hereby lower complications. The primary aim was to evaluate the efficacy of a microteaching program for obtaining ultrasound-guided femoral artery access for ultrasound inexperienced combat medics. The secondary aim was to assess the additional value of innovative echogenic coated needles in ultrasound-guided vascular access.

METHODS

Combat medics participated in a four-step microteaching program. The program consisted of a theoretical and step-by-step practical part with three different models including live and dead tissue & a REBOA Access Task Trainer. During the final test, all participants had to obtain femoral artery access on a pressurized post-mortem human specimen model with both echogenic coated and conventional needles. Self-perceived and observed performance as well as procedure times were scored.

RESULTS

All nine participants succeeded in blood vessel visualization and obtaining vascular access in the two models within 3 minutes and were significantly faster during the second attempt on the pressurized post-mortem human specimen model. Scoring comparison and usability preference by ultrasound inexperienced personnel showed a significant difference in favor of the echogenic coated needles.

CONCLUSION

Microteaching may be an effective approach to train combat medics in obtaining ultrasound-guided percutaneous femoral artery access. The use of echogenic coatings on needles could be a valuable adjunct and provide advantage in obtaining vascular access. Future research should focus on realistic simulation of austere situations and further evaluation of the use of echogenic coated instruments for vascular access in these pre-hospital settings.

Endovascular aortic occlusion improves return of spontaneous circulation after longer periods of cardiopulmonary resuscitation: A translational study in pigs

Introduction

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has emerged as an adjunct to CPR for nontraumatic cardiac arrest (NTCA). This translational study investigated the impact of varying low-flow duration (15- vs 30-mins) on REBOA's hemodynamic performance and ability to achieve return of spontaneous circulation (ROSC) in a porcine model.

Methods

Thirty-two pigs were anesthetized and placed into ventricular fibrillation. All animals received a 4-min no-flow period before CPR was initiated. Animals were randomized into four groups: 15- vs 30-minutes of CPR; REBOA vs. no-REBOA. After completion of 15- or 30-minute low-flow, ACLS was initiated and REBOA was inflated in experimental animals.

Results

In the 15-mins groups, there were no differences in the rates of ROSC between REBOA (4/8, 50%) and control (4/8, 50%; p = 0.99). However, in the 30-min groups, the REBOA animals had a significantly higher rate of ROSC (6/8, 75%) compared to control (1/8, 12.5%; p = 0.04). In the 7-mins after REBOA deployment in the 30-min animals there was a statistically significant difference in coronary perfusion pressure (REBOA 42.1 mmHg, control 3.6 mmHg, p = 0.038). Importantly, 5/6 animals that obtained ROSC in the 30-min group with REBOA re-arrested at least once, with 3/6 maintaining ROSC until study completion.

Conclusion

In our porcine model of NTCA, REBOA preferentially improved hemodynamics and ROSC after a 30-mins period of low-flow CPR. REBOA may be a viable strategy to improve ROSC after prolonged downtime, however, more hemodynamic support will be required to maintain ROSC.

Current trends in the management of out of hospital cardiac arrest (OHCA)

Sudden cardiac arrest remains a relevant problem with a significant number of deaths worldwide. Although survival rates have more than tripled over the last 20 years (4% in 2001 vs. 14% in 2020), survival rates with good neurological outcomes remain persistently low, representing a major socioeconomic problem. Every minute of delay from patient collapse to start cardiopulmonary resuscitation (CPR) and early defibrillation reduces the chance of survival by approximately 10-12%. Therefore, the time to treatment is a crucial factor in the prognosis of patients with out-of-hospital cardiac arrest (OHCA). Research teams working in the pre-hospital setting are therefore looking for ways to improve the transmission of information from the site of an emergency event and to make it easier for emergency medical dispatch centres (EMDC) to recognise life-threatening conditions with minimal deviation. For emergency unit procedures already at the scene of the event, methods are being sought to efficiently and temporarily replace a non-functioning cardiopulmonary system. In the case of traumatic cardiac arrest (TCA), the focus is mainly on effective affecting non-compressible haemorrhage.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) during cardiac resuscitation increased cerebral perfusion to occurrence of cardiopulmonary resuscitation-induced consciousness, a case report

Consciousness or signs of life may be seen during cardiopulmonary resuscitation (CPR), without return of spontaneous circulation. Such CPR-induced consciousness includes breathing efforts, eye opening, movements of extremities or communication with the rescuers. The consciousness may be CPR-interfering or non-interfering, and typically ends when the resuscitation efforts end. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a potential adjunct treatment to CPR and may increase the arterial blood pressure. We present a case where REBOA increased the arterial blood pressure to the extent that CPR-induced consciousness was seen.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level V.

Prehospital anaesthesiologists experience with cardiopulmonary resuscitation-induced consciousness in Norway - A national cross-sectional survey

Background

During cardiopulmonary resuscitation (CPR) cerebral blood flow may be sufficient to restore some cerebral function, and CPR-induced consciousness (CPRIC) may occur. CPRIC includes signs of life such as gasping, breathing efforts, eye opening, movements of extremities or communication with the rescuers. There is a lack in evidence for prevalence, experience, and possible treatment strategies for CPRIC. This survey aimed to assess prehospital anaesthesiologists experience with CPRIC in Norway.

Methods

A web-based cross-sectional survey. All physicians working at a Norwegian air ambulance, search-and-rescue base or physician-staffed rapid response car were invited to participate.

Result

Out of 177 invited, 115 responded. All were anaesthesiologist, with mean 12.7 (SD 7.2) years of prehospital experience, and 25% had attended more than 200 out-of-hospital cardiac arrests (OHCA). CPRIC was known amongst most physicians prior to the survey and experienced by 91%. Mechanical compression device was used in 79% of cases. The CPRIC were CPR-interfering in 31% of cases. Next-of-kin reported the CPRIC as upsetting in 5% of cases. Medication and/or physical restraint were administered in 75% patients. For patients with CPRIC 50% answered that sedation was needed. If sedation should be provided, 62% answered that this should only be performed by a physician, while 25% answered that both ambulance crew and physicians could provide sedation. Fentanyl, ketamine, and midazolam were suggested as the most appropriate sedation agents.

Conclusion

This nationwide survey indicates that CPRIC during OHCA are well known amongst prehospital anaesthesiologist in Norway. Most patients with CPRIC were treated with chest compression device. Most physicians recommend sedation of patients with CPRIC during resuscitation.

The detrimental effects of intestinal injury mediated by inflammation are limited in cardiac arrest patients: A prospective cohort study

Background

Ischaemic intestines could be a driver of critical illness through an inflammatory response. We have previously published reports on a biomarker for intestinal injury, plasma Intestinal Fatty Acid Binding Protein (IFABP), and inflammatory biomarkers after out-of-hospital cardiac arrest (OHCA). In this post-hoc study we explored the potential indirect effects of intestinal injury mediated through the inflammatory response on organ dysfunction and mortality.

Methods

We measured IFABP and twenty-one inflammatory biomarkers in 50 patients at admission to intensive care unit after OHCA. First, we stratified patients on median IFABP and compared biomarkers between "low" and "high" IFABP. Second, by causal mediation analysis, we assessed effects of IFABP through the two most important inflammatory biomarkers, interleukin (IL)-6 and terminal complement complex (TCC), on day two circulatory variables, Sequential Organ Failure Assessment (SOFA)-score, and 30-day mortality.

Results

Cytokines and complement activation were higher in the high IFABP group. In mediation analysis, patients on the 75th percentile of IFABP, compared to the 25th percentile, had 53% (95% CI, 33-74; p < 0.001) higher risk of dying, where 13 (95% CI, 3-23; p = 0.01) percentage points were mediated through an indirect effect of IL-6. Similarly, the indirect effect of IFABP through IL-6 on SOFA-score was significant, but smaller than potential other effects. Effects through IL-6 on circulatory variables, and all effects through TCC, were not statistically significant and/or small.

Conclusion

Effects of intestinal injury mediated through inflammation on organ dysfunction and mortality were limited. Small, but significant, effects through IL-6 were noted.Trial registration: ClinicalTrials.gov: NCT02648061.

Effect of resuscitative endovascular balloon occlusion of the aorta in nontraumatic out-of-hospital cardiac arrest: a multinational, multicenter, randomized, controlled trial

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) is a significant public health issue worldwide and is associated with low survival rates and poor neurological outcomes. The generation of optimal coronary perfusion pressure (CPP) via high-quality chest compressions is a key factor in enhancing survival rates. However, it is often challenging to provide adequate CPP in real-world cardiopulmonary resuscitation (CPR) scenarios. Based on animal studies and human trials on improving CPP in patients with nontraumatic OHCA, resuscitative endovascular balloon occlusion of the aorta (REBOA) is a promising technique in these cases. This study aims to investigate the benefits of REBOA adjunct to CPR compared with conventional CPR for the clinical management of nontraumatic OHCA.

METHODS

This is a parallel-group, randomized, controlled, multinational trial that will be conducted at two urban academic tertiary hospitals in Korea and Taiwan. Patients aged 20-80 years presenting with witnessed OHCA will be enrolled in this study. Eligible participants must fulfill the inclusion criteria, and written informed consent should be collected from their legal representatives. Patients will be randomly assigned to the intervention (REBOA-CPR) or control (conventional CPR) group. The intervention group will receive REBOA and standard advanced cardiovascular life support (ACLS). Meanwhile, the control group will receive ACLS based on the 2020 American Heart Association guidelines. The primary outcome is the return of spontaneous circulation (ROSC). The secondary outcomes include sustained ROSC, survival to admission, survival to discharge, neurological outcome, and hemodynamic changes.

DISCUSSION

Our upcoming trial can provide essential evidence regarding the efficacy of REBOA, a mechanical method for enhancing CPP, in OHCA resuscitation. Our study aims to determine whether REBOA can improve treatment strategies for patients with nontraumatic OHCA based on clinical outcomes, thereby potentially providing valuable insights and guiding further advancements in this critical public health area.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06031623. Registered on September 9, 2023.

Resuscitative endovascular balloon occlusion of the aorta and resuscitative thoracotomy are associated with similar outcomes in traumatic cardiac arrest

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a minimally invasive alternative to resuscitative thoracotomy (RT) for patients with hemorrhagic shock. However, the potential benefits of this approach remain subject of debate. The aim of this study was to compare the outcomes of REBOA and RT for traumatic cardiac arrest.

METHODS

A planned secondary analysis of the United States Department of Defense-funded Emergent Truncal Hemorrhage Control study was performed. Between 2017 and 2018, a prospective observational study of noncompressible torso hemorrhage was conducted at six Level I trauma centers. Patients were dichotomized by REBOA or RT, and baseline characteristics and outcomes were compared between groups.

RESULTS

A total of 454 patients were enrolled in the primary study, of which 72 patients were included in the secondary analysis (26 underwent REBOA and 46 underwent resuscitative thoracotomy). Resuscitative endovascular balloon occlusion of the aorta patients were older, had a greater body mass index, and were less likely to be the victims of penetrating trauma. Resuscitative endovascular balloon occlusion of the aorta patients also had less severe abdominal injuries and more severe extremity injuries, although the overall injury severity scores were similar. There was no difference in mortality between groups (88% vs. 93%, p = 0.767). However, time to aortic occlusion was longer in REBOA patients (7 vs. 4 minutes, p = 0.001) and they required more transfusions of red blood cells (4.5 vs. 2.5 units, p = 0.007) and plasma (3 vs. 1 unit, p = 0.032) in the emergency department. After adjusted analysis, mortality remained similar between groups (RR, 0.89; 95% confidence interval, 0.71-1.12, p = 0.304).

CONCLUSION

Resuscitative endovascular balloon occlusion of the aorta and RT were associated with similar survival after traumatic cardiac arrest, although time to successful aortic occlusion was longer in the REBOA group. Further research is needed to better define the role of REBOA in trauma.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

[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.

Resuscitative endovascular balloon occlusion of the aorta in out-of-hospital cardiac arrest - A Delphi consensus study for uniform data collection

Background

Evolving research on resuscitative endovascular balloon occlusion of the aorta (REBOA) as an adjunct treatment for out-of-hospital cardiac arrest mandates uniform recording and reporting of data. A consensus on which variables need to be collected may enable comparing and merging data from different studies. We aimed to establish a standard set of variables to be collected and reported in future REBOA studies in out-of-hospital cardiac arrest.

Methods

A four-round stepwise Delphi consensus process first asked experts to propose without restraint variables for future REBOA research in out-of-hospital cardiac arrest. The experts then reviewed the variables on a 5-point Likert scale and ≥75% agreement was defined as consensus. First authors of published papers on REBOA in out-of-hospital cardiac arrest over the last five years were invited to join the expert panel.

Results

The data were collected between May 2022 and December 2022. A total of 28 experts out of 34 primarily invited completed the Delphi process, which developed a set of 31 variables that might be considered as a supplement to the Utstein style reporting of research in out-of-hospital cardiac arrest.

Conclusions

This Delphi consensus process suggested 31 variables that enable future uniform reporting of REBOA in out-of-hospital cardiac arrest.

The end of balloons? Our take on the UK-REBOA trial

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is increasingly used. The recently published UK-REBOA trial aimed to investigate patients suffering haemorrhagic shock and randomized to standard care alone or REBOA as adjunct to standard care and concludes that REBOA may increase the mortality.

MAIN BODY

In this commentary we try to balance the discussion on use of REBOA and address limitations in the UK-REBOA trial that may have influenced the outcome of the study.

CONCLUSION

The situation is complex, and the patients are in extremis. In summary, we do not think this is the end of balloons.

Resuscitation Strategies for Maximizing Survival

There is no single resuscitation strategy that will uniformly improve cardiac arrest outcomes. Traditional vital signs cannot be relied on in cardiac arrest, and the use of continuous capnography, regional cerebral tissue oxygenation, and continuous arterial monitoring are options for use early defibrillation are critical elements of resuscitation. Cardio-cerebral perfusion may be improved with the use of active compression-decompression CPR, an impedance threshold device, and head-up CPR. In refractory shockable arrest, if ECPR is not an option, consider changing defibrillator pad placement and/or double defibrillation, additional medication options, and possibly stellate ganglion block.

Intra-aortic and Intra-caval Balloon Pump Devices in Experimental Non-traumatic Cardiac Arrest and Cardiopulmonary Resuscitation

Intra-aortic balloon pump (IABP) use during CPR has been scarcely studied. Intra-caval balloon pump (ICBP) may decrease backward venous flow during CPR. Mechanical chest compressions (MCC) were initiated after 10 min of cardiac arrest in anesthetized pigs. After 5 min of MCC, IABP (n = 6) or ICBP (n = 6) was initiated. The MCC device and the IABP/ICBP had slightly different frequencies, inducing a progressive peak pressure phase shift. IABP inflation 0.15 s before MCC significantly increased mean arterial pressure (MAP) and carotid blood flow (CBF) compared to inflation 0.10 s after MCC and to MCC only. Coronary perfusion pressure significantly increased with IABP inflation 0.25 s before MCC compared to inflation at MCC. ICBP inflation before MCC significantly increased MAP and CBF compared to inflation after MCC but not compared to MCC only. This shows the potential of IABP in CPR when optimally synchronized with MCC. The effect of timing of intra-aortic balloon pump (IABP) inflation during mechanical chest compressions (MCC) on hemodynamics. Data from12 anesthetized pigs.

Using point-of-care testing for adult patients with out-of-hospital cardiac arrest resuscitated at the emergency department to predict return of spontaneous circulation: Development and external validation of POC-ED-ROSC model

BACKGROUND AND IMPORTANCE

Most prediction models, like return of spontaneous circulation (ROSC) after cardiac arrest (RACA) or Utstein-based (UB)-ROSC score, were developed for prehospital settings to predict the probability of ROSC in patients with out-of-hospital cardiac arrest (OHCA). A prediction model has been lacking for the probability of ROSC in patients with OHCA at emergency departments (EDs).

OBJECTIVE

In the present study, a point-of-care (POC) testing-based model, POC-ED-ROSC, was developed and validated for predicting ROSC of OHCA at EDs.

DESIGN, SETTINGS AND PARTICIPANTS

Prospectively collected data for adult OHCA patients between 2015 and 2020 were analysed. POC blood gas analysis obtained within 5 min of ED arrival was used.

OUTCOMES MEASURE AND ANALYSIS

The primary outcome was ROSC. In the derivation cohort, multivariable logistic regression was used to develop the POC-ED-ROSC model. In the temporally split validation cohort, the discriminative performance of the POC-ED-ROSC model was assessed using the area under the receiver operating characteristic (ROC) curve (AUC) and compared with RACA or UB-ROSC score using DeLong test.

MAIN RESULTS

The study included 606 and 270 patients in the derivation and validation cohorts, respectively. In the total cohort, 471 patients achieved ROSC. Age, initial cardiac rhythm at ED, pre-hospital resuscitation duration, and POC testing-measured blood levels of lactate, potassium and glucose were significant predictors included in the POC-ED-ROSC model. The model was validated with fair discriminative performance (AUC: 0.75, 95% confidence interval [CI]: 0.69-0.81) with no significant differences from RACA (AUC: 0.68, 95% CI: 0.62-0.74) or UB-ROSC score (AUC: 0.74, 95% CI: 0.68-0.79).

CONCLUSION

Using only six easily accessible variables, the POC-ED-ROSC model can predict ROSC for OHCA resuscitated at ED with fair accuracy.

Advanced and Invasive Cardiopulmonary Resuscitation (CPR) Techniques as an Adjunct to Advanced Cardiac Life Support

BACKGROUND

Despite numerous promising innovations, the chance of survival from sudden cardiac arrest has remained virtually unchanged for decades. Recently, technological advances have been made, user-friendly portable devices have been developed, and advanced invasive procedures have been described that could improve this unsatisfactory situation.

METHODS

A selective literature search in the core databases with a focus on randomized controlled trials and guidelines.

RESULTS

Technical aids, such as feedback systems or automated mechanical cardiopulmonary resuscitation (CPR) devices, can improve chest compression quality. The latter, as well as extracorporeal CPR, might serve as a bridge to treatment (with extracorporeal CPR even as a bridge to recovery). Sonography may be used to improve thoracic compressions on the one hand and to rule out potentially reversible causes of cardiac arrest on the other. Resuscitative endovascular balloon occlusion of the aorta might enhance myocardial and cerebral perfusion. Minithoracostomy, pericardiocentesis, or clamshell thoracotomy might resolve reversible causes of cardiac arrest.

CONCLUSIONS

It is crucial to identify those patients who may benefit from an advanced or invasive procedure and make the decision to implement the intervention in a timely manner. As with all infrequently performed procedures, sound education and regular training are paramount.

Advanced interventions in the pre-hospital resuscitation of patients with non-compressible haemorrhage after penetrating injuries

Abstract

Early haemorrhage control and minimizing the time to definitive care have long been the cornerstones of therapy for patients exsanguinating from non-compressible haemorrhage (NCH) after penetrating injuries, as only basic treatment could be provided on scene. However, more recently, advanced on-scene treatments such as the transfusion of blood products, resuscitative thoracotomy (RT) and resuscitative endovascular balloon occlusion of the aorta (REBOA) have become available in a small number of pre-hospital critical care teams. Although these advanced techniques are included in the current traumatic cardiac arrest algorithm of the European Resuscitation Council (ERC), published in 2021, clear guidance on the practical application of these techniques in the pre-hospital setting is scarce. This paper provides a scoping review on how these advanced techniques can be incorporated into practice for the resuscitation of patients exsanguinating from NCH after penetrating injuries, based on available literature and the collective experience of several helicopter emergency medical services (HEMS) across Europe who have introduced these advanced resuscitation interventions into routine practice.

Graphical Abstract

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.

Automated aortic endovascular balloon volume titration prevents re-arrest immediately after return of spontaneous circulation in a swine model of nontraumatic cardiac arrest

Objectives

Endovascular aortic occlusion as an adjunct to cardiopulmonary resuscitation (CPR) for non-traumatic cardiac arrest is gaining interest. In a recent clinical trial, return of spontaneous circulation (ROSC) was achieved despite prolonged no-flow times. However, 66% of patients re-arrested upon balloon deflation. We aimed to determine if automated titration of endovascular balloon volume following ROSC can augment diastolic blood pressure (DBP) to prevent re-arrest.

Methods

Twenty swine were anesthetized and placed into ventricular fibrillation (VF). Following 7 minutes of no-flow VF and 5 minutes of mechanical CPR, animals were subjected to complete aortic occlusion to adjunct CPR. Upon ROSC, the balloon was either deflated steadily over 5 minutes (control) or underwent automated, dynamic adjustments to maintain a DBP of 60 mmHg (Endovascular Variable Aortic Control, EVAC).

Results

ROSC was obtained in ten animals (5 EVAC, 5 REBOA). Sixty percent (3/5) of control animals rearrested while none of the EVAC animals rearrested (p = 0.038). Animals in the EVAC group spent a significantly higher proportion of the post-ROSC period with a DBP > 60 mmHg [median (IQR)] [control 79.7 (72.5–86.0)%; EVAC 97.7 (90.8–99.7)%, p = 0.047]. The EVAC group had a statistically significant reduction in arterial lactate concentration [7.98 (7.4–8.16) mmol/L] compared to control [9.93 (8.86–10.45) mmol/L, p = 0.047]. There were no statistical differences between the two groups in the amount of adrenaline (epinephrine) required.

Conclusion

In our swine model of cardiac arrest, automated aortic endovascular balloon titration improved DBP and prevented re-arrest in the first 20 minutes after ROSC.

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.

Changes in peripheral arterial blood pressure after resuscitative endovascular balloon occlusion of the aorta (REBOA) in non-traumatic cardiac arrest patients

Background

Resuscitative endovascular balloon occlusion of the aorta (REBOA) may be an adjunct treatment to cardiopulmonary resuscitation (CPR). Aortic occlusion may increase aortic pressure and increase the coronary perfusion pressure and the cerebral blood flow. Peripheral arterial blood pressure is often measured during or after CPR, however, changes in peripheral blood pressure after aortic occlusion is insufficiently described. This study aimed to assess changes in peripheral arterial blood pressure after REBOA in patients with out of hospital cardiac arrest.

Methods

A prospective observational study performed at the helicopter emergency medical service in Trondheim (Norway). Eligible patients received REBOA as adjunct treatment to advanced cardiac life support. Peripheral invasive arterial blood pressure and end-tidal CO₂ (EtCO₂) was measured before and after aortic occlusion. Differences in arterial blood pressures and EtCO₂ before and after occlusion was analysed with Wilcoxon Signed Rank test.

Results

Five patients were included to the study. The median REBOA procedural time was 11 min and median time from dispatch to aortic occlusion was 50 min. Two patients achieved return of spontaneous circulation. EtCO₂ increased significantly 60 s after occlusion, by a mean of 1.16 kPa (p = 0.043). Before occlusion the arterial pressure in the compression phase were 43.2 (range 12–112) mmHg, the mean pressure 18.6 (range 4–27) mmHg and pressure in the relaxation phase 7.8 (range − 7 – 22) mmHg. After aortic occlusion the corresponding pressures were 114.8 (range 23–241) mmHg, 44.6 (range 15–87) mmHg and 14.8 (range 0–29) mmHg. The arterial pressures were significant different in the compression phase and as mean pressure (p = 0.043 and p = 0.043, respectively) and not significant in the relaxation phase (p = 0.223).

Conclusion

This study is, to our knowledge, the first to assess the peripheral invasive arterial blood pressure response to aortic occlusion during CPR in the pre-hospital setting. REBOA application during CPR is associated with a significantly increase in peripheral artery pressures. This likely indicates improved central aortic blood pressure and warrants studies with simultaneous peripheral and central blood pressure measurement during aortic occlusion.

Trial registration

The study is registered in ClinicalTrials.gov (NCT03534011).