Resuscitative Endovascular Balloon Occlusion of the Aorta for Hemorrhage Control in Trauma Patients: An Evidence-Based Review

Short: Prediction of fetal blood oxygen content in response to partial occlusion of maternal aorta

Acute hemorrhage in pregnancy may lead to maternal and/or fetal morbidity or mortality. In emergency medicine, blockage of the aorta via an inflatable endovascular balloon, technically referred to Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA), is used to manage hemorrhage. However, the application of REBOA in pregnancy needs to strike a balance between two competing objectives of limiting maternal blood loss and ensuring fetal wellness, for which one would need to predict the impact of regulated blood pressure on fetal wellness. To address this problem, we propose an efficient machine learning-based method to predict the temporal impact of the distal Mean Arterial Blood Pressure (dMAP) controlled by the REBOA on the oxygen content in the fetal blood. Evaluation of the algorithm on data collected from in-vivo experiments from pregnant ewe animal models exhibits mean absolute error of 0.61, 1.09, 1.42, 1.70 mmHg, and coefficient of determination of 0.95, 0.86, 0.76, 0.64 for prediction of partial pressure of oxygen in fetal arterial blood, a key predictor of fetal wellness, in 2.5, 5, 7.5, 10-minute prediction horizons, respectively.

Emerging approaches to pre-hospital hemorrhage control: a narrative review

In the United States, trauma claims the lives of over 150,000 civilians each year. In military settings, trauma and exsanguination result in 50% of combat related deaths. The majority of these deaths result from uncontrolled non-compressible hemorrhage. Non-compressible hemorrhage often results from deep vascular injuries within the torso, however can also occur secondary to penetrating injuries that involve the extremities. Given the high mortality rates for non-compressible hemorrhage, rapid and effective management of patients suffering from hemorrhage is essential to good patient outcomes. Consequently, there has been increasing interest in solutions for point-of-injury hemorrhage control in trauma and military medicine. Undoubtedly there is a great need for prehospital hemostatic interventions that can be deployed by trained and untrained personnel. Since 2001, various hemostatic agents have been developed, each with its advantages based upon the type and severity of injury, wound size, wound location, accessibility to injury site, and the coagulation status of the patient. These agents are often used in the military setting as a temporizing measure prior to definitive therapy and include techniques such as resuscitative endovascular balloon occlusion of the aorta (REBOA) and bioengineered agents including ResQFoam, RevMedx’s XSTAT, Tranexamic acid (TXA), and QuikClot Combat Gauze (QCG). Here, we review the indications, composition, technique, efficacy, and outcomes of these hemostatic agents.

Feasibility and Clinical Outcome of Reboa in Patients with Impending Traumatic Cardiac Arrest

BACKGROUND

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) may improve Systolic Blood Pressure (SBP) in hypovolemic shock. It has, however, not been studied in patients with impending traumatic cardiac arrest (ITCA). We aimed to study the feasibility and clinical outcome of REBOA in patients with ITCA using data from the ABOTrauma Registry.

METHODS

Retrospective and prospective data on the use of REBOA from 16 centers globally were collected. SBP was measured both at pre- and post-REBOA inflation. Data collected included patients' demography, vascular access technique, number of attempts, catheter size, operator, zone and duration of occlusion, and clinical outcome.

RESULTS

There were 74 patients in this high-risk patient group. REBOA was performed on all patients. A 7-10Fr catheter was used in 66.7% and 58.5% were placed on the first attempt, 52.1% through blind insertion and 93.2% inflated in Zone I, 64.8% for a period of 30 to 60 min, 82.1% by ER doctors, trauma surgeons, or vascular surgeons. SBP significantly improved to 90 mm Hg following the inflation of REBOA. 36.6% of the patients survived.

CONCLUSIONS

Our study has shown that REBOA may be performed in patients with ITCA, SBP can be elevated, and 36.6% of the patients survived if REBOA placement is successful.

[Traumatic vascular injuries]

Since the beginning of the twentieth century and the implementation of anesthesia and antisepsis, the knowledge and possibilities in treatment of vascular injury has continuously improved. We are currently experiencing improvements in the preclinical management due to various damage control procedures. Depending on the type of vascular injury (blunt, sharp, with or without defect) the treatment can be conservative in individual cases but in most cases endovascular or open vascular surgery is necessary. In the twenty-first century the surgical treatment by direct suture or replacement of the vessel by a graft is increasingly being supplemented by various endovascular procedures.

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.

Resuscitative Endovascular Balloon Occlusion of the Aorta Process Improvement: Examining a Novel Case Evaluation Tool and Standardized Simulations

A quality improvement project was undertaken. The objectives of this study were to describe an original case evaluation tool, discuss barriers encountered, present a standardized simulation course, and evaluate the efficacy of this course. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emerging adjunct in the trauma bay for patients with noncompressible subdiaphragmatic hemorrhage. Compared with the alternative (emergency department thoracotomy), it is less invasive and allows for continuation of chest compressions, and early studies suggest a positive effect on mortality. Infrequent utilization of REBOA limits provider and support staff exposure to its indications and technical skills required to deploy the device. Furthermore, there is no standardized evaluation tool for collecting and reporting REBOA-related data. The REBOA Review Tool was designed to easily evaluate all the steps involved in deploying the REBOA tool and was implemented at our institution without difficulty. This tool provided meaningful feedback for areas that required improvement including ease of information retrieval and documentation of sheath removal. Standardized simulation courses were performed to further improve provider and support staff confidence in using the REBOA tool. Analysis of pre- and postsimulation surveys showed significant improvement in participants' confidence in their understanding and utilization of the REBOA tool and its indications. REBOA placement is a low-volume but high-impact procedure. Therefore, simulations to prepare and a standardized tool to learn from prior experience are vital to improving patient care.

Efficacy of intermittent versus standard resuscitative endovascular balloon occlusion of the aorta in a lethal solid organ injury model

BACKGROUND

High-grade solid organ injury is a major cause of mortality in trauma. Use of resuscitative endovascular balloon occlusion of the aorta (REBOA) can be effective but is limited by ischemia-reperfusion injury. Intermittent balloon inflation/deflation has been proposed as an alternative, but the safety and efficacy prior to operative hemorrhage control is unknown.

METHODS

Twenty male swine underwent standardized high-grade liver injury, then randomization to controls (N = 5), 60-min continuous REBOA (cR, n = 5), and either a time-based (10-minute inflation/3-minute deflation, iRT = 5) or pressure-based (mean arterial pressure<40 during deflation, iRP = 5) intermittent schedule. Experiments were concluded after 120 minutes or death.

RESULTS

Improved overall survival was seen in the iRT group when compared to cR (p < 0.01). Bleeding rate in iRT (5.9 mL/min) was significantly lower versus cR and iRP (p = 0.02). Both iR groups had higher final hematocrit (26% vs. 21%) compared to cR (p = 0.03). Although overall survival was lower in the iRP group, animals surviving to 120 minutes with iRP had decreased end organ injury (Alanine aminotransferase [ALT] 33 vs. 40 in the iRT group, p = 0.03) and lower lactate levels (13 vs. 17) compared with the iRT group (p = 0.03). No differences were seen between groups in terms of coagulopathy based on rotational thromboelastometry.

CONCLUSION

Intermittent REBOA is a potential viable adjunct to improve survival in lethal solid organ injury while minimizing the ischemia-reperfusion seen with full REBOA. The time-based intermittent schedule had the best survival and prolonged duration of tolerable zone 1 placement. Although the pressure-based schedule was less reliable in terms of survival, when effective, it was associated with decreased acidosis and end-organ injury.

Feasibility study for implementation of resuscitative balloon occlusion of the aorta in peri-arrest, exsanguinating trauma at an adult level 1 Australian trauma centre

OBJECTIVE

This prospective, observational, interventional study sought to determine if the introduction of resuscitative balloon occlusion of the aorta (REBOA) at an Australian adult major trauma centre would improve survival for major trauma patients.

METHODS

Patients aged 18-60 years, transported directly from scene with exsanguinating, sub-diaphragmatic haemorrhage and hypovolaemic shock (systolic BP <70 mmHg or hypovolaemic cardiac arrest) were eligible for recruitment and followed up until hospital discharge (ACTRN12618000550202).

RESULTS

During the 14-month study period (17 January 2015 to 12 March 2016) 3032 patients were admitted direct from scene with an overall mortality of 97 (3.71%). Of these patients 3019 had trauma centre vital signs recorded in the data set (99.57%) and 1523 were between the ages of 18-60, including 143 patients with a shock index of >1.0 (4.74%). There were 13 (0.43%) patients with a systolic BP <70 mmHg and/or cardiorespiratory arrest on arrival. The mortality in this group was six out of 13 (46.15%). Of these 13 patients, there were two (0.07% of the total cohort) where REBOA was attempted. There were no eligible patients for whom REBOA was achieved. None of the six patients who died would have benefited from REBOA deployment.

CONCLUSIONS

Despite considerable training and resource allocation to ensure 24-h availability, the introduction of REBOA failed to effectively demonstrate any impact on patient outcome. Despite retrospective literature supporting the introduction of REBOA, in this 14-month prospective study there was no evidence of benefit. Further studies may define indications and subgroups of patients who may benefit.

Thoracic trauma in military settings: a review of current practices and recommendations

PURPOSE OF REVIEW

To examine current literature on thoracic trauma related to military combat and to explore its relevance to the civilian population.

RECENT FINDINGS

Damage control resuscitation (DCR) has improved the management of hemorrhaging trauma patients. Permissive hypotension below 110 mmHg and antifibrinolytic use during DCR is widely accepted, whereas the use of freeze-dried plasma and whole blood is gaining popularity. The Modified Physiologic Triaging Tool can be used for primary triage and it may have applications in civilian trauma systems. Although Tactical Combat Casualty Care protocol recommends the Cric-Key device for surgical cricothyroidotomies, other devices may offer comparable performance. Recommendations for regional anesthesia after blunt trauma are not well defined. Increasing amounts of evidence favor the use of extracorporeal membrane oxygenation for refractory hypoxemia and resuscitative endovascular balloon occlusion of the aorta (REBOA) for severe hemorrhage. REBOA outcomes are potentially improved by partial occlusion and small 7 Fr catheters.

SUMMARY

The Global War on Terror has provided opportunities to better understand and treat thoracic trauma in military settings. Trauma registries and other data sources have contributed to significant advancements in the management of thoracic trauma in military and civilian populations.