REBOA at Role 2 Afloat: resuscitative endovascular balloon occlusion of the aorta as a bridge to damage control surgery in the military maritime setting

Balloons on the battlefield: REBOA implementation in the UK Defence Medical Services

Established in 2018, the Defence Endovascular Resuscitation (DefER) group recognised that resuscitative endovascular balloon occlusion of the aorta (REBOA) offered an option to improve survival in battle casualties dying from haemorrhage, particularly in remote and austere surgical settings. Following a successful jHub opportunity assessment, DefER purchased training and operational kit at pace. By 1 April 2019, the first forward surgical group undertook a bespoke endovascular training and assessment package. Results of the pilot were presented back to a jHub 4* Innovation Board, which initially awarded £500 000 to fund the project to full implementation. Med Op Cap provided a solution to establish REBOA as a core capability on to the 370 modules. REBOA catheters and arterial access kit are now available to deployed Role 2 facilities across defence as an adjunct to damage control resuscitation in specific circumstances. REBOA has, from a standing start, gained pan-Defence Medical Services (DMS) endorsement and has been integrated into deployed damage control resuscitation. To establish a new resuscitation capability across all Role 2 platforms within 15 months of inception represents implementation at pace. This agility was unlocked by empowering clinicians to develop the platform in conjunction with commercial procurement. This article describes how this innovative pathway facilitated the rapid introduction of a lifesaving haemorrhage control technique to equip DMS clinicians.

Impact of military medicine on civilian medical practice in the UK from 2009 to 2020

INTRODUCTION

The positive impact of advances in military medicine and the influence these have had on civilian medical practice have been well documented throughout history: this review will be looking specifically between 2009 and 2020.

AIMS

Review of innovations that have been implemented or have influenced civilian practice within the areas of trauma, disease outbreak management and civilian systems between 2009 and 2020. This review will also aim to explore the impact that working with or within the military can have on individuals within civilian healthcare systems and the future challenges we face to maintain skills.

RESULTS

Using a narrative approach to this review, we found that there have been numerous changes to trauma management within the UK, based on military practice and research during conflict, which have improved survival outcomes. In addition, the use of niche military skills as part of a coordinated response, during both internal and international disease outbreaks, are thought to have supported civilian systems enabling an efficient and prolonged response. Furthermore, adaptation of military concepts and their application to the NHS through consultant-led prehospital teams, centralisation of specialties in the form of major trauma centres and the introduction of guidelines to manage 'major incidents and mass casualty events' in 2018 have improved patient outcomes.

CONCLUSION

From 2009 to 2020, lessons learnt from the British and other nations' militaries have been integrated into UK practice and have likely contributed to improved outcomes in the management of major incidents both nationally and internationally.

Delays in Surgical Intervention and Temporary Hemostasis Using Resuscitative Endovascular Balloon Occlusion of the aorta (REBOA): Influence of Time to Operating Room on Mortality

BACKGROUND

The optimal candidates for resuscitative endovascular balloon occlusion of the aorta (REBOA) remain unclear. We hypothesized that patients who experience delays in surgical intervention would benefit from REBOA.

METHODS

Using the Japan Trauma Databank (2014-2019), patients transferred to the operating room (OR) within 3 h were identified. Patients treated with REBOA were matched with those without REBOA using propensity scores, and further divided based on the transfer time to OR: ≤ 1 h (early), 1-2 h (delayed), and >2 h (significantly-delayed). Survival to discharge was compared.

RESULTS

Among 5258 patients, 310 underwent REBOA. In 223 matched pairs, patients treated with REBOA had improved survival (56.5% vs. 31.8%; p < 0.01), although in-hospital mortality was reduced by REBOA only in the delayed and significantly-delayed subgroups (HR = 0.43 [0.28-0.65] and 0.42 [0.25-0.71]).

CONCLUSIONS

REBOA-treated trauma patients who experience delays in surgical intervention (>1 h) have improved survival.

Progress on combat damage control resuscitation/surgery and its application in the Chinese People's Liberation Army

Damage control resuscitation (DCR) and damage control surgery (DCS) has now been developed as a well-established standard of care for severely injured civilian patients worldwide. On the other hand, the application of combat DCR/DCS has saved the lives of thousands of severely injured casualties in several wars during the last two decades. This article describes the great progress on DCR/DCS in the last two decades and its application in the Chinese People's Liberation Army (PLA). The main development of the advanced theories of combat DCR/DCS including the global integration of DCR/DCS, application of remote battlefield DCR, balanced hemostatic resuscitation in combat hospitals and enhancement of en route DCR. There are two key factors that determine the feasibility of combat DCR: one is the availability of resources and supplies to implement the advanced theories of combat DCR/DCS, the other is the availability of qualified personnel who master the skills needed for the implementation of DCR/DCS. In the PLA, the advanced theories of combat DCR/DCS have now been widely accepted, and some of related advanced products, such as fresh-frozen plasma, packed red blood cells, and platelets, have been available in Level III medical facilities. In conclusion, great progress in combat DCR/DCS has been achieved in recent years, and the Chinese PLA is keeping good pace with this development, although there is still room for improvement.

Titrate to equilibrate and not exsanguinate! Characterization and validation of a novel partial resuscitative endovascular balloon occlusion of the aorta catheter in normal and hemorrhagic shock conditions

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a significant advancement in the control of noncompressible truncal hemorrhage. However, its ischemic burden and reperfusion injury following balloon deflation limits its utilization. Partial restoration of aortic flow during REBOA has the potential to balance hemorrhage control and ischemia. This study validates the mechanics, physiology, and optimal partial flow rates using a prototype partial REBOA (pREBOA) device.

METHODS

Twenty-five swine underwent placement of aortic flow probes and zone 1 pREBOA. Experiment 1 (N = 5) animals were not injured and assessed the tested the catheters ability to titrate and control flow. Experiment 2 (N = 10) added 20% hemorrhage and either solid organ, or abdominal vascular injury to compare flow rate and rebleeding from injuries. Experiment 3 (N = 10) swine were similarly prepared, hemorrhaged, and underwent pREBOA at set partial flow rates for 2 hours followed by complete deflation for 30 minutes.

RESULTS

Balloon volume at minimum flow (mean, 0.09 L/min) was 3.5 mL to 6.0 mL. Half maximal flow was achieved with 56.5% of maximum balloon inflation. Partial REBOA allowed very fine titration of flow rates. Rebleeding occurred at 0.45 L/min to 0.83 L/min. Distal flow of 0.7 L/min had 50% survival, 0.5 had 100% survival, and 0.3 L had 50% survival with mean end lactates of 9.6, 12.6, and 13.3, respectively. There was a trend toward hyperkalemia and hypocalcemia in nonsurvivors.

CONCLUSION

The pREBOA device demonstrated a high level of titratability for restoration of aortic flow. An optimal partial flow of 0.5 L/min was effective at hemorrhage control while limiting the burden of ischemic injury, and extending the tolerable duration of zone 1 occlusion. Aggressive calcium supplementation prior to and during partial occlusion and reperfusion may be warranted to prevent hyperkalemic arrest.

Effect of partial and complete aortic balloon occlusion on survival and shock in a swine model of uncontrolled splenic hemorrhage with delayed resuscitation

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is accepted as a resuscitation adjunct and bridge to definitive hemostasis. The ischemic burden of REBOA may be mitigated by a partial REBOA (P-REBOA) strategy permitting longer occlusion times and military use for combat trauma. We evaluated REBOA and P-REBOA in a swine multiple trauma model with uncontrolled solid organ hemorrhage and delayed resuscitation and surgical hemostasis.

METHODS

Anesthetized swine (51.9 ± 2.2 kg) had 20 mL/kg hemorrhage and closed femur fracture. Splenic transection was performed and free bleeding permitted for 10 minutes. Controls (n = 5) were hemorrhaged but had no REBOA, REBOA (n = 8) had 60 minutes complete zone 1 occlusion, P-REBOA (n = 8) had 15 minutes complete occlusion and 45 minutes 50% occlusion. Splenectomy was performed and plasma (15 mL/kg) resuscitation initiated 5 minutes prior to deflation. Resuscitation goal was 80 mm Hg systolic with epinephrine as needed. Animals were monitored for 6 hours.

RESULTS

An initial study with 120-minute occlusion had universal fatality in three REBOA (upon deflation) and three P-REBOA animals (after 60 minutes inflation). With 60-minute occlusion, mortality was 100%, 62.5%, and 12.5% in the control, REBOA, and P-REBOA groups, respectively (p < 0.05). Survival time was shorter in controls (120 ± 89 minutes) than REBOA and P-REBOA groups (241 ± 139, 336 ± 69 minutes). Complete REBOA hemorrhaged less during inflation (1.1 ± 0.5 mL/kg) than Control (5.6 ± 1.5) and P-REBOA (4.3 ± 1.4), which were similar. Lactate was higher in the REBOA group compared with the P-REBOA group after balloon deflation, remaining elevated. Potassium increased in REBOA after deflation but returned to similar levels as P-REBOA by 120 minutes.

CONCLUSION

In a military relevant model of severe uncontrolled solid organ hemorrhage 1-hour P-REBOA improved survival and mitigated hemodynamic and metabolic shock. Two hours of partial aortic occlusion was not survivable using this protocol due to ongoing hemorrhage during inflation. There is potential role for P-REBOA as part of an integrated minimally invasive field-expedient hemorrhage control and resuscitation strategy.

The REBOA window: a cadaveric study delineating the optimum site for austere cannulation of the femoral artery for resuscitative endovascular balloon occlusion of the aorta

INTRODUCTION

Haemorrhage is the major cause of early mortality following traumatic injury. Patients suffering from non-compressible torso haemorrhage are more likely to suffer early death. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) can be effective in initial resuscitation; however, establishing swift arterial access is challenging, particularly in a severe shock. This is made more difficult by anatomical variability of the femoral vessels.

METHODS

The femoral vessels were characterised in 81 cadaveric lower limbs, measuring specifically the distance from the inferior border of the inguinal ligament to the distal part of the origin of the profunda femoris artery (PFA), and from the distal part of the origin of the PFA to where the femoral vein lies posterior to and is completely overlapped by the femoral artery.

RESULTS

The femoral vein lay deep to the femoral artery at a mean distance of 105 mm from the inferior border of the inguinal ligament. The PFA arose from the femoral artery at a mean distance of 51.1 mm from the inguinal ligament. From the results, it is predicted that the PFA originates from the common femoral artery approximately 24 mm from the inguinal ligament, and the femoral vein is completely overlapped by the femoral artery by 67.7 mm distal from the inguinal ligament, in 95% of subjects.

CONCLUSIONS

Based on the results, proposed is an 'optimal access window' of up to 24 mm inferior to the inguinal ligament for common femoral arterial catheterisation for pre-hospital REBOA, or more simply within one finger breadth.

Thoracic Injury in Patients Injured by Explosions on the Battlefield and in Terrorist Incidents

Thoracic injury is common on the battlefield and in terrorist attacks, occurring in 10% to 70% of patients depending on the type of weapons used. Typical injuries seen include bullet, blast, and fragment injuries to the thorax, which are often associated with injuries to other parts of the body. Initial treatment prehospital and in the ED is carried out according to the principles of Tactical Combat Casualty Care or other standard trauma management systems. Immediately life-threatening problems including catastrophic hemorrhage are dealt with rapidly, and early consideration is given to CT scanning or rapid surgical intervention where appropriate. All patients should be given lung-protective ventilation. Treatment of these patients in the critical care unit is complicated by the severity of associated injuries and by features specific to combat trauma including blast lung injury, a high incidence of delirium, unusual infections such as colonization with multidrug-resistant Acinetobacter baumannii complex, and sometimes invasive fungal infections. A minority of patients with blast lung injury in published series have been successfully treated with prolonged respiratory support with high-frequency oscillatory ventilation and extracorporeal membrane oxygenation. The role of newer treatment options such as resuscitative endovascular balloon occlusion of the aorta is not yet known. In this article we review the relatively sparse literature on this group of patients and provide practical advice based on the literature and our institution's extensive experience of managing battlefield casualties.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is associated with improved survival in severely injured patients: A propensity score matching analysis

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a technique for temporary control of arterial hemorrhage. However, its effectiveness and clinical outcomes are unclear.

METHODS

Using a nationwide database (2004-2016) in Japan, trauma patients with survival data were identified. Patients were divided between REBOA and non-REBOA groups, and a propensity score was developed using multivariate logistic regression. Survival to discharge was compared between the groups after propensity score matching.

RESULTS

Among 82,371 patients included in this study, 385 were treated with REBOA. After propensity score matching, 117 pairs were selected. Survival to discharge was significantly higher among patients treated with REBOA than among those treated without REBOA (53 [45.3%] vs. 38 [32.5%]; odds ratio = 1.72; 95% CI = 1.01-2.93; p = 0.04).

CONCLUSIONS

REBOA use was associated with improved survival to discharge and should therefore be considered during the management of severely injured trauma patients.

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) in the Management of Trauma Patients: A Systematic Literature Review

Resuscitative endovascular balloon occlusion of the aorta (REBOA) represents an innovative method by which noncompressible bleeding in the torso can be mitigated until definitive treatment can be obtained. To perform a systematic review of the literature on the use of the REBOA in trauma patients. An English and Spanish literature search was performed using MEDLINE, PubMed, and Scopus, from 1948 to 2018. Keywords used were aortic balloon occlusion, resuscitative endovascular balloon, REBOA, hemorrhage, and resuscitative endovascular balloon occlusion of the aorta. The eligilibility criteria included only original and human subject articles. Nontrauma patients, nonbleeding pathology, letters, single case reports, reviews, and pediatric patients were excluded. Two hundred forty-six articles were identified, of which 17 articles were included in this review. The total number of patients was 1340; 69 per cent were men and 31 per cent women. In 465 patients, the aortic zone location was described: 83 per cent the balloon was placed in aortic zone I and 16 per cent in zone III. Systolic blood pressure increased at an average of 52 mmHg before and after aortic occlusion. Although 32 patients (2.4%) presented clinical complications derived from the procedure, no mortality was reported. The trauma-related mortality rate was 58 per cent (776/1340). REBOA is a useful resource for the management of non-compressive torso hemorrhage with promising results in systolic blood pressure and morbidity. Indications for its use include injuries in zones 1 and 3, whereas it is not clear for zone 2 injuries. Additional studies are needed to define the benefits of this procedure.

Large Animal Models of Proximal Aortic Balloon Occlusion in Traumatic Hemorrhage: Review and Identification of Knowledge Gaps Relevant to Expanded Use

BACKGROUND

The aim of this study was to review and summarize the large animal data on resuscitative endovascular balloon occlusion of the aorta (REBOA) for traumatic hemorrhage and identify knowledge gaps pertinent to the proposed broader use of the technique in prehospital situations.

METHODS

A review of published large animal models of traumatic hemorrhage incorporating REBOA with a primary outcome of the effect of aortic occlusion was performed. Data were collected on experimental protocols, hemodynamic effects, resuscitation requirements, mortality, metabolic and tissue consequences of induced ischemia-reperfusion, and effects on hemorrhage volume and other injuries.

RESULTS

A limited number of REBOA studies exist, and there is variability in the species and size of animals used. Various controlled and uncontrolled hemorrhage protocols have been studied, and a number of balloon devices used. Hemodynamic effects of occlusion were consistent as were basic systemic physiological effects. Minimal study of the effects of partial aortic occlusion and hemodynamic and metabolic physiology distal to the balloon has been performed, and partial or complete occlusion times >90 min have not been studied.

CONCLUSIONS

Significant knowledge gaps exist, which are potentially relevant to the expanded use of REBOA. Investigation into the physiology of partial occlusion and the metabolic effects and potential mitigation strategies for large-scale ischemia and reperfusion are particularly needed.

The shipboard Beirut terrorist bombing experience: a historical account and recommendations for preparedness in events of mass neurological injuries

On a Sunday morning at 06:22 on October 23, 1983, in Beirut, Lebanon, a semitrailer filled with TNT sped through the guarded barrier into the ground floor of the Civilian Aviation Authority and exploded, killing and wounding US Marines from the 1st Battalion 8th Regiment (2nd Division), as well as the battalion surgeon and deployed corpsmen. The truck bomb explosion, estimated to be the equivalent of 21,000 lbs of TNT, and regarded as the largest nonnuclear explosion since World War II, caused what was then the most lethal single-day death toll for the US Marine Corps since the Battle of Iwo Jima in World War II. Considerable neurological injury resulted from the bombing. Of the 112 survivors, 37 had head injuries, 2 had spinal cord injuries, and 9 had peripheral nerve injuries. Concussion, scalp laceration, and skull fracture were the most common cranial injuries.Within minutes of the explosion, the Commander Task Force 61/62 Mass Casualty Plan was implemented by personnel aboard the USS Iwo Jima. The wounded were triaged according to standard protocol at the time. Senator Humphreys, chairman of the Preparedness Committee and a corpsman in the Korean War, commented that he had never seen such a well-executed evolution. This was the result of meticulous preparation that included training not only of the medical personnel but also of volunteers from the ship's company, frequent drilling with other shipboard units, coordination of resources throughout the ship, the presence of a meticulous senior enlisted man who carefully registered each of the wounded, the presence of trained security forces, and a drilled and functioning communication system.Viewed through the lens of a neurosurgeon, the 1983 bombings and mass casualty event impart important lessons in preparedness. Medical personnel should be trained specifically to handle the kinds of injuries anticipated and should rehearse the mass casualty event on a regular basis using mock-up patients. Neurosurgery staff should participate in training and planning for events alongside other clinicians. Training of nurses, corpsmen, and also nonmedical personnel is essential. In a large-scale evolution, nonmedical personnel may monitor vital signs, work as scribes or stretcher bearers, and run messages. It is incumbent upon medical providers and neurosurgeons in particular to be aware of the potential for mass casualty events and to make necessary preparations.

Vascular access training for REBOA placement: a feasibility study in a live tissue-simulator hybrid porcine model

Background

The use of resuscitative endovascular balloon occlusion of the aorta (REBOA) in patients with severe haemorrhagic shock is increasing. Obtaining vascular access is a necessary prerequisite for REBOA placement in these situations.

Methods

During the EVTM workshop (September 2017, Örebro, Sweden), 21 individuals participated in this study, 16 participants and five instructors. A formalised curriculum was constructed including basic anatomy of the femoral region and basic training in access materials for REBOA placement in zone 1. Key skills: (1) preparation of endovascular toolkit, (2) achieving vascular access in the model and (3) bleeding control with REBOA. Scoring ranged from 0 to 5 for non-anatomical skills. Identification of anatomical structures was either sufficient (score=1) or insufficient (score=0). Five consultants performed a second identical procedure as a post test.

Results

Consultants had significantly better overall technical skills in comparison with residents (p=0.005), while understanding of surgical anatomy showed no difference. Procedure times differed significantly (p<0.01), with residents having a median procedure time of 3 min and 24 s, consultants 2:33 and instructors 1:09.

Conclusion

This comprehensive training model using a live tissue-simulator hybrid porcine model can be used for femoral access and REBOA placement training in medical personnel with different prior training levels. Higher levels of training are associated with faster procedure times. Further research in open and percutaneous access training is necessary to simulate real-life situations. This training method can be used in a multistep training programme, in combination with realistic moulage and perfused cadaver models.