Feasibility of Pre-Hospital Resuscitative Endovascular Balloon Occlusion of the Aorta in Non-Traumatic Out-of-Hospital Cardiac Arrest

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.

Exploring aortic morphology and determining variable-distance insertion lengths for fluoroscopy-free resuscitative endovascular balloon occlusion of the aorta (REBOA)

BACKGROUND (RATIONALE/PURPOSE/OBJECTIVE)

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is used to temporary control non-compressible truncal hemorrhage (NCTH) as bridge to definitive surgical treatment. The dependence on radiography for safe balloon positioning is one factor that limits the extended use of REBOA in civilian and military pre-hospital settings. We aimed to determine standardized sex and age-based variable-distance catheter insertion lengths for accurate REBOA placement without initial fluoroscopic confirmation.

METHODS

Contrast enhanced CT-scans from a representative sample of a Dutch non-trauma population were retrospectively analyzed. Intravascular distances were measured from the bilateral common femoral artery access points (FAAP) to the middle of the aortic occlusion zones and accompanying boundaries. Means and 95% confidence intervals for the distances from the FAAPs to the boundaries and mid-zone III were calculated for all (combined) sex and age-based subgroups. Optimal insertion lengths and potentially safe regions were determined for these groups. Bootstrap analysis was performed in combination with a 40-mm long balloon introduction simulation to determine error-rates and REBOA placement accuracy for the general population.

RESULTS

In total, 1354 non-trauma patients (694 females) were included. Vascular distances increased with age and were longer in males. The iliofemoral trajectory was 7 mm longer on the right side. The optimal zone I catheter insertion length would be 430 mm. Optimal zone III catheter insertion lengths showed up to 30 mm difference, ranging between 234 and 264 mm. Statistically significant and potentially clinically relevant differences were observed between the anatomical distances and necessary introduction depths for each subgroup.

CONCLUSION

This is the first study to compare aortic morphology and intravascular distances between combined sex and age-based subgroups. As zone III length was consistent, length variability and elongation seem to mainly originate in the iliofemoral trajectory and zone II. The optimal zone I catheter insertion length would be 430 mm. Optimal zone III catheter insertion ranged between 234 and 264 mm. These standardized variable-distance insertion lengths could facilitate safer fluoroscopy-free REBOA in austere, 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.

Age affects vascular morphology and predictiveness of anatomical landmarks for aortic zones in trauma patients: implications for resuscitative endovascular balloon occlusion of the aorta

PURPOSE

Understanding the vascular morphology is fundamental for resuscitative endovascular balloon occlusion of the aorta. This study aimed to evaluate the effect of aging on length and diameter of aorta and iliac arteries in trauma patients, and to investigate the predictiveness of anatomical landmarks for aortic zones.

METHODS

A total of 235 patients in a regional trauma center registry from September 1, 2018, to January 3, 2024, participated in the study. Reconstruction of computed tomography was applied to the torso area. The marginal diameter and length of aorta and iliac arteries were measured. Anatomical landmark distances and aortic marginal lengths were compared.

RESULTS

The length and diameter of aorta and iliac arteries increased with age, and a tortuous and enlarged morphology was observed in older patients. There was a good regression between age and diameter of the aorta. Neither the jugular notch, the xiphisternal joint, nor the umbilicus could reliably represent specific margins of aortic zones. The distance between the mid-sternum and femoral artery (427 ± 25 to 442 ± 25 mm for right, and 425 ± 28 to 440 ± 26 mm for left) was predictive for zone 1 in all groups. The distance between the lower one-third junction of the xiphisternum to the umbilicus and femoral artery (232 ± 19 to 240 ± 17 mm for right, and 229 ± 20 to 237 ± 19 mm for left) was predictive for zone 3 aorta.

CONCLUSION

Aging increases the length and diameter of aorta and iliac arteries, with a tortuous and enlarged morphology in geriatric populations. The mid-sternum and the lower one-third junction of the xiphisternum to the umbilicus were predictive landmarks for zone 1 and zone 3, respectively.

Use of resuscitative endovascular balloon occlusion of the aorta (REBOA) and ultrasound-guided left stellate ganglion block to rescue out of hospital cardiac arrest due to refractory ventricular fibrillation: A case report

Out of hospital cardiac arrest from shockable rhythms that is refractory to standard treatment is a unique challenge. Such patients can achieve neurological recovery even with long low-flow times if perfusion can somehow be restored to the heart and brain. Extracorporeal cardiopulmonary resuscitation is an effective treatment for refractory cardiac arrest if applied early and accurately, but often cannot be directly implemented by frontline providers and has strict inclusion/exclusion criteria. We present the case of a novel treatment strategy for out of hospital cardiac arrest due to refractory ventricular fibrillation utilizing Resuscitative Endovascular Balloon Occlusion of the Aorta-assisted cardiopulmonary resuscitation and intra-arrest left stellate ganglion blockade to achieve return of spontaneous circulation and eventual good neurological outcome after 101 minutes of downtime.

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 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.

The Lancet Commission to reduce the global burden of sudden cardiac death: a call for multidisciplinary action

Despite major advancements in cardiovascular medicine, sudden cardiac death (SCD) continues to be an enormous medical and societal challenge, claiming millions of lives every year. Efforts to prevent SCD are hampered by imperfect risk prediction and inadequate solutions to specifically address arrhythmogenesis. Although resuscitation strategies have witnessed substantial evolution, there is a need to strengthen the organisation of community interventions and emergency medical systems across varied locations and health-care structures. With all the technological and medical advances of the 21st century, the fact that survival from sudden cardiac arrest (SCA) remains lower than 10% in most parts of the world is unacceptable. Recognising this urgent need, the Lancet Commission on SCD was constituted, bringing together 30 international experts in varied disciplines. Consistent progress in tackling SCD will require a completely revamped approach to SCD prevention, with wide-sweeping policy changes that will empower the development of both governmental and community-based programmes to maximise survival from SCA, and to comprehensively attend to survivors and decedents' families after the event. International collaborative efforts that maximally leverage and connect the expertise of various research organisations will need to be prioritised to properly address identified gaps. The Commission places substantial emphasis on the need to develop a multidisciplinary strategy that encompasses all aspects of SCD prevention and treatment. The Commission provides a critical assessment of the current scientific efforts in the field, and puts forth key recommendations to challenge, activate, and intensify efforts by both the scientific and global community with new directions, research, and innovation to reduce the burden of SCD worldwide.

Prehospital Resuscitation: What Should It Be?

Prehospital resuscitation is a dynamic field now being energized by new technologies and a shift in thinking regarding intravascular resuscitation. Growing evidence discourages use of intravenous (IV) crystalloid and colloid solutions in trauma, whereas blood products, particularly whole blood, are becoming preferred. Although randomized clinical trials validating definitive resuscitative protocols are still lacking, most preclinical and clinical indicators support this approach. In addition, emerging technologies such as external and endovascular hemorrhage control devices and extracorporeal perfusion are now being used routinely, even in the prehospital setting in many countries, generating new lines of emerging investigations for trauma specialists.

Haemodynamic impact of aortic balloon occlusion combined with percutaneous left ventricular assist device during cardiopulmonary resuscitation in a swine model of cardiac arrest

AIM

To investigate the effect of tandem use of transient balloon occlusion of the descending aorta (AO) and percutaneous left ventricular assist device (pl-VAD) during cardiopulmonary resuscitation in a large animal model of prolonged cardiac arrest.

METHODS

Ventricular fibrillation was induced and left untreated for 8 minutes followed by 16 minutes of mechanical CPR (mCPR) in 24 swine, under general anesthesia. Animals were randomized to 3 treatment groups (n = 8 per group): A) pL-VAD (Impella CP®) B) pL-VAD+AO, and C) AO. Impella CP® and the aortic balloon catheter were inserted via the femoral arteries. mCPR was continued during treatment. Defibrillation was attempted 3 times starting at minute 28 and then every 4 minutes. Haemodynamic, cardiac function and blood gas measurements were recorded for up to 4 hours.

RESULTS

Coronary perfusion pressure (CoPP) in the pL-VAD+AO Group increased by a mean (SD) of 29.2(13.94) mmHg compared to an increase of 7.1(12.08) and 7.1(5.95) mmHg for groups pL-VAD and AO respectively (p = 0.02). Similarly, cerebral perfusion pressure (CePP) in pL-VAD+AO increased by a mean (SD) of 23.6 (6.11), mmHg compared with 0.97 (9.07) and 6.9 (7.98) mmHg for the other two groups (p < 0.001). The rate of return of spontaneous heartbeat (ROSHB) was 87.5%, 75%, and 100% for pL-VAD+AO, pL-VAD, and AO.

CONCLUSION

Combined AO and pL-VAD improved CPR hemodynamics compared to either intervention alone in this swine model of prolonged cardiac arrest.

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.

A porcine study of ultrasound-guided versus fluoroscopy-guided placement of endovascular balloons in the inferior vena cava (REBOVC) and the aorta (REBOA)

Objectives

In fluoroscopy-free settings, alternative safe and quick methods for placing resuscitative endovascular balloon occlusion of the aorta (REBOA) and resuscitative endovascular balloon occlusion of the inferior vena cava (REBOVC) are needed. Ultrasound is being increasingly used to guide the placement of REBOA in the absence of fluoroscopy. Our hypothesis was that ultrasound could be used to adequately visualize the suprahepatic vena cava and guide REBOVC positioning, without significant time-delay, when compared with fluoroscopic guidance, and compared with the corresponding REBOA placement.

Methods

Nine anesthetized pigs were used to compare ultrasound-guided placement of supraceliac REBOA and suprahepatic REBOVC with corresponding fluoroscopic guidance, in terms of correct placement and speed. Accuracy was controlled by fluoroscopy. Four intervention groups: (1) fluoroscopy REBOA, (2) fluoroscopy REBOVC, (3) ultrasound REBOA and (4) ultrasound REBOVC. The aim was to carry out the four interventions in all animals. Randomization was performed to either fluoroscopic or ultrasound guidance being used first. The time required to position the balloons in the supraceliac aorta or in the suprahepatic inferior vena cava was recorded and compared between the four intervention groups.

Results

Ultrasound-guided REBOA and REBOVC placement was completed in eight animals, respectively. All eight had correctly positioned REBOA and REBOVC on fluoroscopic verification. Fluoroscopy-guided REBOA placement was slightly faster (median 14 s, IQR 13-17 s) than ultrasound-guided REBOA (median 22 s, IQR 21-25 s, p=0.024). The corresponding comparisons of the REBOVC groups were not statistically significant, with fluoroscopy-guided REBOVC taking 19 s, median (IQR 11-22 s) and ultrasound-guided REBOVC taking 28 s, median (IQR 20-34 s, p=0.19).

Conclusion

Ultrasound adequately and quickly guide the placement of supraceliac REBOA and suprahepatic REBOVC in a porcine laboratory model, however, safety issues must be considered before use in trauma patients.

Level of evidence

Prospective, experimental, animal study. Basic science study.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

TEE guided REBOA deflation following ROSC for non-traumatic cardiac arrest

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is most commonly used to manage non-compressible torso hemorrhage. It is also emerging as a promising treatment for non-traumatic refractory cardiac arrest. Aortic occlusion during chest compressions increases cardio-cerebral perfusion, increasing the potential for sustained return of spontaneous circulation (ROSC) or serving as a bridge to extracorporeal cardiopulmonary resuscitation (ECPR). Optimal patient selection and post-ROSC management in such cases is uncertain and not well reported in the literature. We present a case of non-traumatic out-of-hospital cardiac arrest in which REBOA was placed in the emergency department with subsequent ROSC. Transesophageal echocardiography was used to guide post-ROSC REBOA management and balloon deflation.

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

The role of REBOA in patients in traumatic cardiac arrest subsequent to hemorrhagic shock: a scoping review

Purpose

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a useful adjunct in treatment of patients in severe hemorrhagic shock. Hypothetically, REBOA could benefit patients in traumatic cardiac arrest (TCA) as balloon occlusion of the aorta increases afterload and may improve myocardial performance leading to return of spontaneous circulation (ROSC). This scoping review was conducted to examine the effect of REBOA on patients in TCA.

Methods

This scoping review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Extension for Scoping Reviews (PRISMA-ScR) Statement. PubMed, EMBASE.com and the Web of Science Core Collection were searched. Articles were included if they reported any data on patients that underwent REBOA and were in TCA. Of the included articles, data regarding SBP, ROSC and survival were extracted and summarized.

Results

Of 854 identified studies, 26 articles met criteria for inclusion. These identified a total of 785 patients in TCA that received REBOA (presumably less because of potential overlap in patients). This review shows REBOA elevates mean SBP in patients in TCA. The achievement of ROSC after REBOA deployment ranged from 18.2% to 67.7%. Survival to discharge ranged from 3.5% to 12.1%.

Conclusion

Overall, weak evidence is available on the use of REBOA in patients in TCA. This review, limited by selection bias, indicates that REBOA elevates SBP and may benefit ROSC and potentially survival to discharge in patients in TCA. Extensive further research is necessary to further clarify the role of REBOA during TCA.

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.

Emergency department initiated resuscitative endovascular balloon occlusion of the aorta (REBOA) for out-of-hospital cardiac arrest is feasible and associated with improvements in end-tidal carbon dioxide

Objectives

Out-of-hospital cardiac arrest (OHCA) claims the lives of approximately 350,000 people in the United States each year. Resuscitative endovascular balloon occlusion of the aorta (REBOA) when used as an adjunct to advanced cardiac life support may improve cardio-cerebral perfusion. Our primary research objective was to determine the feasibility of emergency department (ED)-initiated REBOA for OHCA patients in an academic urban ED.

Methods

This was a single-center, single-arm, early feasibility trial that used REBOA as an adjunct to advanced cardiac life support (ACLS) in OHCA. Subjects under 80 years with witnessed OHCA and who received cardiopulmonary rescuitation (CPR) within 6 minutes were eligible.

Results

Five patients were enrolled between February 2020 and April 2021. The procedure was successful in all patients and 4 of 5 (80%) patients had transient return of spontaneous circulation (ROSC) after aortic occlusion. Unfortunately, all patients re-arrested soon after intra-aortic balloon deflation and none survived to hospital admission. At 30 seconds post-aortic occlusion, investigators noted a statistically significant increase in end tidal carbon dioxide of 26% (95% confidence interval, 10%, 44%).

Conclusion

Initiating REBOA for OHCA patients in an academic urban ED setting is feasible. Aortic occlusion during chest compressions is temporally associated with improvements in end tidal carbon dioxide 30 seconds after aortic occlusion. Four of 5 patients achieved ROSC after aortic occlusion; however, deflation of the intra-aortic balloon quickly led to re-arrest and death in all patients. Future research should focus on the utilization of partial-REBOA to prevent re-arrest after ROSC, as well as the optimal way to incorporate this technique with other endovascular reperfusion strategies.

The effectiveness of portable ultrasound-guided resuscitative endovascular balloon occlusion of the aorta for stopping iliac artery hemorrhage during first aid pre-hospital: a randomized control animal trial

PURPOSE

This study aimed at to comparing the effectiveness of portable ultrasound guided REBOA vs. traditional manual extracorporeal compression in stopping iliac artery hemostasis.

METHODS

Twelve swine were included in this study (treatment group vs. control group, 6:6). A biopsy device was used to create an iliac artery rupture and hemorrhage in each swine. After 30 s of bleeding, the treatment group received REBOA under the guidance of ultrasound, whereas the control group received traditional manual extracorporeal compression. General physiological conditions were recorded at 0 s (baseline, T1), 30 s (initiation of therapies to stop bleeding, T2), 10 min (T3) and 30 min (T4) after bleeding. Intraperitoneal and retroperitoneal hemorrhage and specimens of iliac artery were collected after all swine were euthanized.

RESULTS

One swine was excluded because of accidental death not related to the experiment; thus, 11 swine were analyzed in this study. The general physiological characteristics of the two groups showed no difference at T1. Hemorrhagic shock occurred in both groups. After the hemostatic procedure was performed, systolic pressure, diastolic pressure and heart rate first increased significantly between T2 and T3, and then became stable between T3 and T4; these indicators in the control group deteriorated over time. The total blood loss in the treatment group (1245.23 ± 190.07 g) was much significantly less than that in the control group (2605.63 ± 291.67 g) with p < 0.001.

CONCLUSIONS

Performing REBOA under the guidance of portable ultrasound is an effective way to stop bleeding. It suggests a potential alternative method for iliac artery hemostasis in the pre-hospital setting.

Resuscitative endovascular occlusion of the aorta (REBOA) as a mechanical method for increasing the coronary perfusion pressure in non-traumatic out-of-hospital cardiac arrest patients

AIM

of the study Resuscitative endovascular balloon occlusion of the aorta (REBOA), originally designed to block blood flow to the distal part of the aorta by placing a balloon in trauma patients, has recently been shown to increase coronary perfusion in cardiac arrest patients. This study evaluated the effect of REBOA on aortic pressure and coronary perfusion pressure (CPP) in non-traumatic out of-hospital cardiac arrest (OHCA) patients.

METHODS

Adult OHCA patients with cerebral performance category 1 or 2 prior to cardiac arrest, and without evidence of aortic disease, were enrolled from January to December 2021. Aortic pressure and right atrial pressure were measured before and after balloon occlusion. The CPP was calculated using the measured aortic and right atrial pressures, and the values before and after the balloon occlusion were compared.

RESULTS

Fifteen non-traumatic OHCA patients were enrolled in the study. The median call to balloon time was 46.0 (IQR, 38.0-54.5) min. The median CPP before and after balloon occlusion was 13.5 (IQR, 5.8-25.0) and 25.2 (IQR, 12.0-44.6) mmHg, respectively (P = 0.001). The median increase in the estimated CPP after balloon occlusion was 86.7%.

CONCLUSIONS

The results of this study suggest that REBOA may increase the CPP during cardiopulmonary resuscitation in patients with non-traumatic OHCA. Additional studies are needed to investigate the effect on clinical 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.

Use of a disposable vascular pressure device to guide balloon inflation of resuscitative endovascular balloon occlusion of the aorta: a bench study

Resuscitative endovascular balloon occlusion of the aorta (REBOA) for rapid hemorrhage control is increasingly being used in trauma management. Its beneficial hemodynamic effects on unstable patients beyond temporal hemostasis has led to growing interest in its use in other patient populations, such as during cardiac arrest from nontraumatic causes. The ability to insert the catheters without fluoroscopic guidance makes the technique available in the prehospital setting. However, in addition to correct positioning, challenges include reliably achieving aortic occlusion while minimizing the risk of balloon rupture. Without fluoroscopic control, inflation of the balloon relies on estimated aortic diameters and on the disappearing pulse in the contralateral femoral artery. In the case of cardiac arrest or absent palpable pulses, balloon inflation is associated with excess risk of overinflation and adverse events (vessel damage, balloon rupture). In this bench study, we examined how the pressure in the balloon is related to the surrounding blood pressure and the balloon's contact with the vessel wall in two sets of experiments, including a pulsatile circulation model. With this data, we developed a rule of thumb to guide balloon inflation of the ER-REBOA catheter with a simple disposable pressure-reading device (COMPASS). We recommend slowly filling the balloon with saline until the measured balloon pressure is 160 mmHg, or 16 mL of saline have been used. If after 16 mL the balloon pressure is still below 160 mmHg, saline should be added in 1-mL increments, which increases the pressure target about 10 mmHg at each step, until the maximum balloon pressure is reached at 240 mmHg (= 24 mL inflation volume). A balloon pressure greater than 250 mmHg indicates overinflation. With this rule and a disposable pressure-reading device (COMPASS), ER-REBOA balloons can be safely filled in austere environments where fluoroscopy is unavailable. Pressure monitoring of the balloon allows for recognition of unintended deflation or rupture of the balloon.

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).

[Extracorporeal cardiopulmonary resuscitation for treatment of out-of-hospital cardiac arrest]

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) affects ca. 75,000 people each year in Germany and is associated with a limited prognosis and a high mortality. Extracorporeal cardiopulmonary resuscitation (eCPR) using arteriovenous extracorporeal membrane oxygenation (av-ECMO) systems is an additional option for treatment, which is increasingly more widespread and since 2020 anchored in the guideline algorithm.

METHODS

A selective search of the literature was carried out in PubMed and Embase focusing on studies that investigated eCPR for OHCA. Furthermore, clinical studies on this topic that are currently recruiting and running are summarized.

RESULTS

The available data on the benefits of eCPR for OHCA are mostly based on retrospective cohort studies. A survival advantage and an advantage in the neurological outcome could be derived from these data for selected patients treated with eCPR vs. conventionally resuscitated patients (CPR). This effect could be confirmed by two current randomized controlled studies. Studies which are currently running are investigating if out-of-hospital ECMO cannulation at the earliest time possible at the site of OHCA of patients could be associated with a better survival.

CONCLUSION

Despite a current scarcity of data, a survival advantage for eCPR treatment in selected OHCA patients must be assumed. If this can be substantiated by other high-quality studies, it seems to be indicated to evaluate if and to what extent resource-intensive eCPR programs can be comprehensively established.

Goal-directed cardiopulmonary resuscitation for refractory out-of-hospital cardiac arrest in the emergency Department: A feasibility study

Aim

To describe the feasibility of prospective measurement of intra-arrest diastolic blood pressure (DBP) and goal-directed treatment of refractory out-of-hospital cardiac arrest (OHCA) in the emergency department (ED).

Methods

Retrospective case series performed at an urban, tertiary-care hospital from 12/1/2018 - 12/31/2019. We studied consecutive adults presenting with refractory, non-traumatic OHCA treated with haemodynamic-targeted resuscitation that entailed placement of a femoral arterial catheter, transduction of continuous BP during CPR, and administration of vasopressors (1 mg noradrenaline) and, if applicable, Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA), to achieve DBP ≥ 40 mmHg. Feasibility was measured by the success rate and time to achieve arterial catheterization and BP transduction. Additional outcomes included the change in DBP with vasopressor administration and occurrence of sustained ROSC.

Results

Goal-directed treatment was successfully performed in 8/9 (89%) patients. Arterial access required 1.5 (interquartile range (IQR) 1-2) attempts and BP transduction occurred within 10.5 ± 2.4 minutes of patient arrival. Noradrenaline slightly increased DBP (pre 21.6 ± 8.3 mmHg, post 26.1 ± 12.1 mmHg, p < 0.025), but only 4/23 (17%) doses resulted in DBP ≥ 40 mmHg. REBOA was attempted in 2/8 (25%) patients and placed successfully in both cases. Three (37.5%) patients achieved ROSC, but none survived to hospital discharge.

Conclusions

In ED patients with refractory OHCA, measurement of DBP during CPR and titration of resuscitation to a DBP goal is feasible. Future research incorporating this approach should seek to develop haemodynamic-targeted treatment strategies for OHCA patients that do not achieve ROSC with initial resuscitation.

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

Background

Survival after out-of-hospital cardiac arrest (OHCA) is poor and dependent on high-quality cardiopulmonary resuscitation. Resuscitative endovascular balloon occlusion of the aorta (REBOA) may be advantageous in non-traumatic OHCA due to the potential benefit of redistributing the cardiac output to organs proximal to the aortic occlusion. This theory is supported by data from both preclinical studies and human case reports.

Methods

This multicentre trial will enrol 200 adult patients, who will be randomised in a 1:1 ratio to either a control group that receives advanced cardiovascular life support (ACLS) or an intervention group that receives ACLS and REBOA. The primary endpoint will be the proportion of patients who achieve return of spontaneous circulation with a duration of at least 20 min. The secondary objectives of this trial are to measure the proportion of patients surviving to 30 days with good neurological status, to describe the haemodynamic physiology of aortic occlusion during ACLS, and to document adverse events.

Discussion

Results from this study will assess the efficacy and safety of REBOA as an adjunctive treatment for non-traumatic OHCA. This novel use of REBOA may contribute to improve treatment for this patient cohort.

Trial registration

The trial is approved by the Regional Committee for Medical and Health Research Ethics in Norway (reference 152504) and is registered at ClinicalTrials.gov (reference NCT04596514) and as Universal Trial Number WHO: U1111-1253-0322.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05477-1.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Resuscitative endovascular occlusion of the aorta (REBOA) for refractory out of hospital cardiac arrest. An Utstein-based case series

AIMS

Out of hospital cardiac arrest (OHCA) is still a leading cause of mortality worldwide. In recent years, resuscitative endovascular balloon occlusion of the aorta (REBOA) has been progressively studied as an adjunct to standard advanced life support (ALS) in both traumatic and non-traumatic refractory OHCA. Since January 2019, the REBOA procedure has been applied to all the patients experiencing both traumatic and non-traumatic refractory OHCA (≥15 min of cardiopulmonary resuscitation) not eligible for ECPR for clinical or logistic reasons. We aimed at describing the feasibility and effects of REBOA performed both in the Emergency Department and in the pre-hospital environment served by the local HEMS for refractory OHCA.

METHODS

Twenty consecutive patients experiencing refractory OHCA and in whom REBOA was attempted in 2019 and 2020 were included in the study, Utstein data and REBOA specific variables were recorded.

RESULTS

Successful catheter placement was achieved in 18 out of 20 patients, 11 of these were non-traumatic OHCAs while 7 were traumatic OHCAs, the 2 failures were related to repeated arterial puncture failure. Median time between the EMS dispatch and REBOA catheter placing attempt was 46 min. An increase in etCO₂ over 10 mmHg was observed after balloon inflation in 12 out of 18 patients (8/11 non-traumatic and 4/7 traumatic OHCAs), a sustained ROSC was observed in 5 patients (1 traumatic and 4 non-traumatic OHCA) that were subsequently admitted to the ICU. Four out of the 5 patients reached the criteria for brain death in the subsequent 24 h while one patient experienced another episode of refractory cardiac arrest in ICU and subsequently died.

CONCLUSION

Our data confirm the feasibility of REBOA technique as an adjunct to ALS in both the ED and prehospital phase and most of the treated patients experienced a transient ROSC after balloon inflation while 5 out of 18 experienced a sustained ROSC. However, while in the trauma setting increasing evidence suggests an improved survival when REBOA is applied to refractory OHCA, in non-traumatic OHCA this has yet to be demonstrated and large studies are needed.

Needs assessment of resuscitative endovascular balloon occlusion of the aorta (REBOA) in patients with major haemorrhage: a cross-sectional study

Background

Resuscitative endovascular balloon occlusion of the aorta (REBOA) can be used as an adjunct treatment in traumatic abdominopelvic haemorrhage, ruptured abdominal aortic aneurysms, postpartum haemorrhage (PPH), gastrointestinal bleeding and iatrogenic injuries during surgery. This needs assessment study aims to determine the number of patients eligible for REBOA in a typical Norwegian population.

Methods

This was a retrospective cross-sectional study based on data obtained from blood bank registries and the Norwegian Trauma Registry for the years 2017–2018. Patients who received ≥4 units of packed red blood cells (PRBCs) within 6 hours and met the anatomical criteria for REBOA or patients with relevant Abbreviated Injury Scale codes with concurrent hypotension or transfusion of ≥4 units of PRBCs within 6 hours were identified. A detailed two-step chart review was performed to identify potentially eligible REBOA candidates. Descriptive data were collected and compared between subgroups using non-parametric tests for statistical significance.

Results

Of 804 patients eligible for inclusion, 53 patients were regarded as potentially REBOA eligible (corresponding to 5.7 per 100 000 adult population/year). Of these, 19 actually received REBOA. Among the identified eligible patients, 44 (83%) had a non-traumatic aetiology. Forty-two patients (79%) were treated at a tertiary care hospital. Fourteen (78%) of the REBOA procedures were due to PPH.

Conclusion

The number of patients potentially eligible for REBOA after haemorrhage is low, and most cases are non-traumatic. Most patients were treated at a tertiary care hospital. The exclusion of non-traumatic patients results in a substantial underestimation of the number of potentially REBOA-eligible patients.

Optimizing hemodynamic function during cardiopulmonary resuscitation

PURPOSE OF REVIEW

The purpose of this narrative review is to provide an update on hemodynamics during cardiopulmonary resuscitation (CPR) and to describe emerging therapies to optimize perfusion.

RECENT FINDINGS

Cadaver studies have shown large inter-individual variations in blood distribution and anatomical placement of the heart during chest compressions. Using advanced CT techniques the studies have demonstrated atrial and slight right ventricular compression, but no direct compression of the left ventricle. A hemodynamic-directed CPR strategy may overcome this by allowing individualized hand-placement, drug dosing, and compression rate and depth. Through animal studies and one clinical before-and-after study head-up CPR has shown promising results as a potential strategy to improve cerebral perfusion. Two studies have demonstrated that placement of an endovascular balloon occlusion in the aorta (REBOA) can be performed during ongoing CPR.

SUMMARY

Modern imaging techniques may help increase our understanding on the mechanism of forward flow during CPR. This could provide new information on how to optimize perfusion. Head-up CPR and the use of REBOA during CPR are novel methods that might improve cerebral perfusion during CPR; both techniques do, however, still await clinical testing.

Resuscitative endovascular balloon occlusion of the aorta vs epinephrine in the treatment of non-traumatic cardiac arrest in swine

Background

The administration of epinephrine in the management of non-traumatic cardiac arrest remains recommended despite controversial effects on neurologic outcome. The use of resuscitative endovascular balloon occlusion of the aorta (REBOA) could be an interesting alternative. The aim of this study was to compare the effects of these 2 strategies on return of spontaneous circulation (ROSC) and cerebral hemodynamics during cardiopulmonary resuscitation (CPR) in a swine model of non-traumatic cardiac arrest.

Results

Anesthetized pigs were instrumented and submitted to ventricular fibrillation. After 4 min of no-flow and 18 min of basic life support (BLS) using a mechanical CPR device, animals were randomly submitted to either REBOA or epinephrine administration before defibrillation attempts. Six animals were included in each experimental group (Epinephrine or REBOA). Hemodynamic parameters were similar in both groups during BLS, i.e., before randomization. After epinephrine administration or REBOA, mean arterial pressure, coronary and cerebral perfusion pressures similarly increased in both groups. However, carotid blood flow (CBF) and cerebral regional oxygenation saturation were significantly higher with REBOA as compared to epinephrine administration (+ 125% and + 40%, respectively). ROSC was obtained in 5 animals in both groups. After resuscitation, CBF remained lower in the epinephrine group as compared to REBOA, but it did not achieve statistical significance.

Conclusions

During CPR, REBOA is as efficient as epinephrine to facilitate ROSC. Unlike epinephrine, REBOA transitorily increases cerebral blood flow and could avoid its cerebral detrimental effects during CPR. These experimental findings suggest that the use of REBOA could be beneficial in the treatment of non-traumatic cardiac arrest.

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.

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.

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

BACKGROUND

Hemorrhage accounts for >30% of trauma-related mortalities. Use of resuscitative endovascular balloon occlusion of the aorta (REBOA) for temporary hemostasis in the civilian population remains controversial. We aim to investigate REBOA practices through analysis of surgeon and trauma center characteristics, implementation, patient characteristics, and overall opinions.

METHODS

An anonymous 30-question standardized online survey on REBOA use was administered to active trauma surgeon members of the Eastern Association for the Surgery of Trauma.

RESULTS

A total of 345 responses were received, and 130/345 (37.7%) reported REBOA being favorable, 42 (12.2%) reported REBOA unfavorably, and 173 (50.1%) were undecided. The majority of respondents (87.6%) reported REBOA performance in the trauma bay. 170 (49.3%) of respondents reported having deployed REBOA at least once over the past 2 years. 80.0% reported blunt trauma being the most common mechanism of injury in REBOA patients. Resuscitative endovascular balloon occlusion of the aorta deployment in zone 3 of the aorta was significantly higher in patients reported to suffer a pelvic fracture or pelvic hemorrhage, whereas REBOA deployment in zone 1 was significantly higher among patients reported to suffer hepatic, splenic, or other intra-abdominal hemorrhage (P < .05).

CONCLUSION

Among survey respondents, frequency of REBOA use was low along with knowledge of clear indications for use. While current REBOA usage among respondents appeared to model current guidelines, additional research regarding REBOA indications, ideal patient populations, and outcomes is needed in order to improve REBOA perception in trauma surgeons and increase frequency of use.

Randomized blinded trial of automated REBOA during CPR in a porcine model of cardiac arrest

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) reportedly elevates arterial blood pressure (ABP) during non-traumatic cardiac arrest.

OBJECTIVES

This randomized, blinded trial of cardiac arrest in pigs evaluated the effect of automated REBOA two minutes after balloon inflation on ABP (primary endpoint) as well as arterial blood gas values and markers of cerebral haemodynamics and metabolism.

METHODS

Twenty anesthetized pigs were randomized to REBOA inflation or sham-inflation (n = 10 in each group) followed by insertion of invasive monitoring and a novel, automated REBOA catheter (NEURESCUE® Catheter & NEURESCUE® Assistant). Cardiac arrest was induced by ventricular pacing. Cardiopulmonary resuscitation was initiated three min after cardiac arrest, and the automated REBOA was inflated or sham-inflated (blinded to the investigators) five min after cardiac arrest.

RESULTS

In the inflation compared to the sham group, mean ABP above the REBOA balloon after inflation was higher (inflation: 54 (95%CI: 43-65) mmHg; sham: 44 (33-55) mmHg; P = 0.06), and diastolic ABP was higher (inflation: 38 (29-47) mmHg; sham: 26 (20-33) mmHg; P = 0.02), and the arterial to jugular oxygen content difference was lower (P = 0.04). After return of spontaneous circulation, mean ABP (inflation: 111 (95%CI: 94-128) mmHg; sham: 94 (95%CI: 65-123) mmHg; P = 0.04), diastolic ABP (inflation: 95 (95%CI: 78-113) mmHg; sham: 78 (95%CI: 50-105) mmHg; P = 0.02), CPP (P = 0.01), and brain tissue oxygen tension (inflation: 315 (95%CI: 139-491)% of baseline; sham: 204 (95%CI: 75-333)%; P = 0.04) were higher in the inflation compared to the sham group.

CONCLUSION

Inflation of REBOA in a porcine model of non-traumatic cardiac arrest improves central diastolic arterial pressure as a surrogate marker of coronary artery pressure, and cerebral perfusion.

INSTITUTIONAL PROTOCOL NUMBER

2017-15-0201-01371.

Shortening Ambulance Response Time Increases Survival in Out-of-Hospital Cardiac Arrest

Background The ambulance response time in out-of-hospital cardiac arrest (OHCA) has doubled over the past 30 years in Sweden. At the same time, the chances of surviving an OHCA have increased substantially. A correct understanding of the effect of ambulance response time on the outcome after OHCA is fundamental for further advancement in cardiac arrest care. Methods and Results We used data from the SRCR (Swedish Registry of Cardiopulmonary Resuscitation) to determine the effect of ambulance response time on 30-day survival after OHCA. We included 20 420 cases of OHCA occurring in Sweden between 2008 and 2017. Survival to 30 days was our primary outcome. Stratification and multiple logistic regression were used to control for confounding variables. In a model adjusted for age, sex, calendar year, and place of collapse, survival to 30 days is presented for 4 different groups of emergency medical services (EMS)-crew response time: 0 to 6 minutes, 7 to 9 minutes, 10 to 15 minutes, and >15 minutes. Survival to 30 days after a witnessed OHCA decreased as ambulance response time increased. For EMS response times of >10 minutes, the overall survival among those receiving cardiopulmonary resuscitation before EMS arrival was slightly higher than survival for the sub-group of patients treated with compressions-only cardiopulmonary resuscitation. Conclusions Survival to 30 days after a witnessed OHCA decreases as ambulance response times increase. This correlation was seen independently of initial rhythm and whether cardiopulmonary resuscitation was performed before EMS-crew arrival. Shortening EMS response times is likely to be a fast and effective way of increasing survival in OHCA.

The use of resuscitative endovascular balloon occlusion of the aorta (REBOA) for non-traumatic cardiac arrest: A review

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been proposed as a novel approach to managing non-traumatic cardiac arrest (NTCA). During cardiac arrest, cardiac output ceases and perfusion of vital organs is compromised. Traditional advanced cardiac life support (ACLS) measures and cardiopulmonary resuscitation are often unable to achieve return of spontaneous circulation (ROSC). During insertion of REBOA a balloon-tipped catheter is placed into the femoral artery and advanced in a retrograde manner into the aorta while the patient is undergoing cardiopulmonary resuscitation (CPR). The balloon is then inflated to fully occlude the aorta. The literature surrounding the use of aortic occlusion in non-traumatic cardiac arrest is limited to animal studies, case reports and one recent non-controlled feasibility trial. In both human and animal studies, preliminary data show that REBOA may improve coronary and cerebral perfusion pressures and key physiologic parameters during cardiac arrest resuscitation, and animal data have demonstrated improved rates of ROSC. Multiple questions remain before REBOA can be considered as an adjunct to ACLS. If demonstrated to be effective clinically, REBOA represents a potentially cost-effective and generalizable intervention that may improve quality of life for patients with non-traumatic cardiac arrest.

Zone 3 REBOA does not provide hemodynamic benefits during nontraumatic cardiac arrest

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) may be a novel intervention to improve cardiopulmonary resuscitation (CPR) quality during cardiac arrest. Zone 1 supraceliac aortic occlusion improves coronary and cerebral blood flow. It is unknown if Zone 3 occlusion distal to the renal arteries offers a similar physiologic benefit while maintaining blood flow to organs above the point of occlusion.

METHODS

Fifteen swine were anesthetized, instrumented, and placed into ventricular fibrillation. Mechanical CPR was immediately initiated. After 5 min of CPR, Zone 1 REBOA, Zone 3 REBOA, or no intervention (control) was initiated. Hemodynamic variables were continuously recorded for 30 min.

RESULTS

There were no significant differences between groups before REBOA deployment. Once REBOA was deployed, Zone 1 animals had statistically greater diastolic blood pressure compared to control (median [IQR]: 19.9 mmHg [9.5-20.5] vs 3.9 mmHg [2.4-4.8], p = .006). There were no differences in diastolic blood pressure between Zone 1 and Zone 3 (8.6 mmHg [5.1-13.1], p = .10) or between Zone 3 and control (p = .10). There were no significant differences in systolic blood pressure, cerebral blood flow, or time to return of spontaneous circulation (ROSC) between groups.

CONCLUSION

In our swine model of cardiac arrest, Zone 1 REBOA improved diastolic blood pressure when compared to control. Zone 3 does not offer a hemodynamic benefit when compared to no occlusion. Unlike prior studies, immediate use of REBOA after arrest did not result in an increase in ROSC rate, suggesting REBOA may be more beneficial in patients with prolonged no-flow time.

INSTITUTIONAL PROTOCOL NUMBER

FDG20180024A.