Resuscitative Endovascular Balloon Occlusion Of The Aorta Placement Research Articles

Use of resuscitative endovascular balloon occlusion of the aorta (REBOA) in a multidisciplinary approach for management of traumatic haemorrhagic shock: 10-year retrospective experience from a French level 1 trauma centre

BackgroundThe present study investigated an institutional multidisciplinary strategy for managing traumatic haemorrhagic shock by integrating the placement of REBOA (resuscitative endovascular balloon occlusion of the aorta) by anaesthesiologist-intensivists. MethodsAll severe trauma patients who received percutaneous REBOA placement between January 2013 and December 2022 in our level 1 trauma centre were retrospectively analysed. The data collected included the clinical context, indications and location of REBOA, durations of aortic occlusion (AO), choice of haemostatic procedures and surgical teams, and specific complications. ResultsIn total, 38 trauma patients were included in the present study (mean age = 41 years [standard deviation = 21 years], 31 [82 %] were male, and median injury severity score was 62.5 [inter-quartile range (IQR) = 45–75]). REBOA was always placed by anaesthesiologist-intensivists, who comprised 68 % of the senior physicians (13/19) in our trauma team over the period. Twenty-eight AOs (74 %) were performed in zone 1 and 10 (26 %) in zone 3. Twelve patients (32 %) received REBOA upon circulatory arrest. Routes following REBOA placement comprised: computed tomography scan = 47 %, operating room = 34 %, angiography = 3 %, emergency room thoracotomy = 5 %, and prematurely died = 11 %. Duration of AO was 38 min (IQR = 32–44 min) in zone 1 and 78 min (IQR = 48–112 min) in zone 3. Mortality rate was 66 % (95 % CI 51–81 %) and higher in cases of AO in zone 1 (79 % versus 30 %, p = 0.018) or concomitant with circulatory arrest (92 % versus 54 %, p = 0.047). No ischemic limb needed an intervention and three endothelial injuries required delayed endovascular stenting. ConclusionsPercutaneous REBOA placement by anaesthesiologist-intensivists included in the multidisciplinary management of traumatic haemorrhagic shock was associated with acceptable time of AO and local complications similar to those observed in other series.

Resuscitative endovascular balloon occlusion of the aorta in the patient with obesity.

Palpation of anatomic landmarks is difficult in patients with obesity, which could increase difficulty of achieving femoral access and resuscitative endovascular balloon occlusion of the aorta (REBOA) placement. The primary aim of this study was to examine the association between obesity and successful REBOA placement. We hypothesized that higher body mass index (BMI) would decrease first-attempt success and increase time to successful aortic occlusion (AO). A review of the Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery (AORTA) registry was performed on patients who underwent REBOA placement with initiation systolic blood pressure >0 mm Hg from years 2013-2022. Patients were excluded if they received cardiopulmonary resuscitation on arrival, underwent open AO, or missing data entries for variables of interest. Body mass index categorization was as follows: non-obese (<30), class I (30-34.9), class II (35-39.9), and class III (40+) obesity. Patients were also stratified by access technique, including use of palpation or ultrasound guidance. Inclusion criteria were met by 410 patients. On binary analysis, no primary outcomes of interest, including rate of success, time to placement, or mortality, were significantly impacted by BMI. Among BMI subgroups, there was no statistical difference in injury severity, admission systolic blood pressure (SBP), or augmented SBP. At initiation of aortic occlusion, patients with class II and class III obesity had higher median SBP compared with non- and class I obese patients (p = 0.03). Body mass index subgroup did not impact likelihood of first-attempt success or conversion to open procedure. When stratified by access technique, there was no difference in success rates, time to success or mortality between groups. Body habitus did not impact success of REBOA placement, time to successful AO, or mortality. Further, ultrasound guidance was not superior to landmark palpation for arterial access. Following traumatic injury without hemodynamic collapse, obesity should not deter providers from considering REBOA placement. Therapeutic/Care management, Observational, Cross-sectional; Level IV.

Using computed tomography to evaluate anatomic landmarks in taiwanese trauma patients for insertion of resuscitative endovascular balloon occlusion of the aorta: A retrospective cohort study.

Hemorrhage, particularly from non-compressible torso hemorrhage (NCTH) in the abdominopelvic region, is a leading cause of preventable trauma deaths. Resuscitative endovascular balloon occlusion of the aorta (REBOA), designed for aortic occlusion, has emerged as a tool for temporary hemorrhage control in recent years. However, attaining optimal REBOA placement in diverse demographic groups, such as Asian populations, may pose challenges owing to unique anatomical and physiological differences. This retrospective study analyzed trauma patients who underwent torso computed tomography (CT) at tertiary hospitals in Taiwan from January 2014 to January 2017. The OsiriX software was used to measure the endovascular lengths in the CT images. Among the 223 patients, the median vascular lengths and body measurements were higher in males. The optimal fixed insertion length was identified as 47.5cm for zone 1 with 99.43% accuracy and 25.5cm with 82.1% accuracy for zone 3. The landmark-guided method showed 100% accuracy for zone 1 when using the mid-sternum and 94.6% for zone 3 with the umbilicus as the guide with the distance between the umbilicus, xiphoid process, and pubic ramus. External validation confirmed the accuracy of the landmark-guided method. For zone 1 occlusions, a range of 44-48cm insertion length cross-referenced with the mid-sternal landmark is recommended. For zone 3 occlusions, using the umbilicus as a guide with the distance between the umbilicus, xiphoid process, and pubic ramus provided the highest accuracy.

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.MethodsContrast 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.ResultsIn 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.ConclusionThis 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.

The employment of resuscitative endovascular balloon occlusion of the aorta in deployed settings.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been often used in place of open aortic occlusion for management of hemorrhagic shock in trauma. There is a paucity of data evaluating REBOA usage in military settings. We queried the Department of Defense Trauma Registry (DODTR) for all cases with at least one intervention or assessment available within the first 72 h after injury between 2007 and 2023. We used relevant procedural codes to identify the use of REBOA within the DODTR, and we used descriptive statistics to characterize its use. We identified 17 cases of REBOA placed in combat settings from 2017 to 2019. The majority of these were placed in the operating room (76%) and in civilian patients (70%). A penetrating mechanism caused the injury in 94% of cases with predominantly the abdomen and extremities having serious injuries. All patients subsequently underwent an exploratory laparotomy after REBOA placement, with moderate numbers of patients having spleen, liver, and small bowel injuries. The majority (82%) of included patients survived to hospital discharge. We describe 17 cases of REBOA within the DODTR from 2007 to 2023, adding to the limited documentation of patients undergoing REBOA in military settings. We identified patterns of injury in line with previous studies of patients undergoing REBOA in military settings. In this small sample of military casualties, we observed a high survival rate.

Resuscitative Endovascular Balloon Occlusion of the Aorta in Non-Traumatic Out-of-Hospital Cardiac Arrest: A State-of-the-Art Review

Out-of-hospital cardiac arrest (OHCA) is one of the most important causes of death worldwide. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an interesting new device that has been developed as a bridge therapy to treat trauma patients with non-compressible torso hemorrhage. REBOA has also been tested in non-traumatic OHCA, but the results are inconclusive. The aim of this review is to describe the state of the art in the use of REBOA for the management of non-traumatic out-of-hospital cardiac arrest. We performed a state-of-the-art review of the literature, searching for the therapeutic role of REBOA in the management of non-traumatic OHCA. We interviewed PubMed, Central, and Embase, and searched for citations before May 2023 using these criteria: “non-traumatic out-of-hospital cardiac arrest” and “resuscitative endovascular balloon occlusion of the aorta”. We selected only observational studies because controlled trials have not been published yet. All studies demonstrated the feasibility of REBOA placement in the management of non-traumatic OHCA and the improvement of all perfusion markers. Although some important uncertainties still remain, REBOA has the potential to become a new cornerstone in the therapy of OHCA and change the management of cardiac arrest, especially in remote locations which require a long time for scene arrival and an even longer time for metropolitan hospital arrival, where an ECPR is available.

Propensity Score Analysis of Resuscitative Endovascular Balloon Occlusion of the Aorta: Zone-1 Versus Zone-3 Resuscitative Endovascular Balloon Occlusion of the Aorta Odds of Mortality

IntroductionThere are two zones for the placement of a Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) in trauma patients: above the mesenteric vessels (Zone-1) or below the renal arteries (Zone-3). Zone-1 REBOA diverts blood away from the visceral organs which leads to a systemic inflammatory response and reperfusion injury. We hypothesized that patients undergoing Zone-1 REBOA placement had a higher odds of mortality. MethodsThe 2017-2019 Trauma Quality Improvement Program database was queried for patients undergoing either Zone-1 or Zone-3 REBOA. We excluded all patients with prehospital cardiac arrest. We compared Zone-1 versus Zone-3 REBOA using a 1:2 propensity-score model, matching for age, mechanism, sex, hypotension, tachycardia, blunt solid organ injury grade, pelvic fracture, and injuries to the aorta, iliac artery, iliac vein, and inferior vena cava. ResultsWe matched 130 Zone-1 REBOA patients to 260 Zone-3 REBOA patients. There were no statistically significant differences in the matched variables (P > 0.05). Compared to Zone-3 REBOA, patients with Zone-1 REBOA who survived ≥48 h had similar rates of acute kidney injury (18.6% versus 10.9%, P = 0.19). Zone-1 REBOA patients had a higher mortality rate (71.4% versus 48.8%, P = 0.002) and mortality odds ratio (OR) (OR 1.85, OR 1.18-2.89, P = 0.007). Zone-1 REBOA remained associated with a higher odds of mortality after controlling for traumatic brain injury and injury severity score (OR 1.86, OR 1.18-2.92, P = 0.007). ConclusionsCompared to Zone-3, using a REBOA in Zone-1 is associated with higher odds of mortality. The use of REBOA Zone-1 deployment should be done with caution.

Critical systolic blood pressure threshold for endovascular aortic occlusion-A multinational analysis to determine when to place a REBOA.

Systolic blood pressure (SBP) is a potential indicator that could guide when to use a resuscitative endovascular balloon occlusion of the aorta (REBOA) in trauma patients with life-threatening injuries. This study aims to determine the optimal SBP threshold for REBOA placement by analyzing the association between SBP pre-REBOA and 24-hour mortality in severely injured hemodynamically unstable trauma patients. We performed a pooled analysis of the aortic balloon occlusion (ABO) trauma and AORTA registries. These databases record the details related to the use of REBOA and include data from 14 countries worldwide. We included patients who had suffered penetrating and/or blunt trauma. Patients who arrived at the hospital with a SBP pre-REBOA of 0 mm Hg and remained at 0 mm Hg after balloon inflation were excluded. We evaluated the impact that SBP pre-REBOA had on the probability of death in the first 24 hours. A total of 1,107 patients underwent endovascular aortic occlusion, of these, 848 met inclusion criteria. The median age was 44 years (interquartile range [IQR], 27-59 years) and 643 (76%) were male. The median injury severity score was 34 (IQR, 25-45). The median SBP pre-REBOA was 65 mm Hg (IQR, 49-88 mm Hg). Mortality at 24 hours was reported in 279 (32%) patients. Math modeling shows that predicted probabilities of the primary outcome increased steadily in SBP pre-REBOA below 100 mm Hg. Multivariable mixed-effects analysis shows that when SBP pre-REBOA was lower than 60 mm Hg, the risk of death was more than 50% (relative risk, 1.5; 95% confidence interval, 1.17-1.92; p = 0.001). In patients who do not respond to initial resuscitation, the use of REBOA in SBPs between 60 mm Hg and 80 mm Hg may be a useful tool in resuscitation efforts before further decompensation or complete cardiovascular collapse. The findings from our study are clinically important as a first step in identifying candidates for REBOA. Prognostic and Epidemiological; Level IV.

Transition ofResuscitative Endovascular Balloon Occlusion ofthe Aorta from Zone 3 to Zone 1 to Treat Hemodynamic Collapse during Continued Hemorrhage.

Noncompressible torso hemorrhage (NCTH) accounts for most potentially survivable deaths on the battlefield. Treatment of NCTH is challenging, especially in far-forward environments with limited capabilities. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has shown promise in the care of patients with NCTH. REBOA involves introducing a balloon catheter into the descending aorta in a specific occlusion region (zones 1, 2, or 3) and acts as a hemorrhage control adjunct with resuscitative support. The balloon is placed in zone 3 in the infrarenal aorta for high junctional or pelvic injuries and in zone 1 proximal to the diaphragm for torso hemorrhage. Zone 1 REBOA provides more resuscitative support than zone 3; however, the potential for ischemia and reperfusion injuries is greater with zone 1 than with zone 3 REBOA placement. This study aims to determine the possible benefit of transitioning the REBOA balloon from zone 3 to zone 1 to rescue a patient with ongoing venous bleeding and impending cardiovascular collapse. Yorkshire male swine (70-90 kg, n = 6 per group) underwent injury to the femoral artery, which was allowed to bleed freely for 60 s, along with a simultaneous controlled venous hemorrhage. After 60 s, the arterial bleed was controlled with hemostatic gauze and zone 3 REBOA was inflated. Five hundred milliliters of Hextend was used for initial fluid resuscitation. The controlled venous bleed continued until a mean arterial pressure (MAP) of 30 mmHg was reached to create an impending cardiovascular collapse. The animals were then randomized into either continued zone 3 REBOA or transition from zone 3 to zone 1 REBOA. Following 30 min, a "hospital phase" was initiated, consisting of cessation of the venous hemorrhage, deflation of the REBOA balloon, and transfusion of one unit of whole blood administered along with saline and norepinephrine to maintain a MAP of 60 mmHg or higher. The animals then underwent a 2-h observation period. Survival, hemodynamics, and blood chemistries were compared between groups. No significant differences between groups were observed in hemodynamic or laboratory values at baseline, postinitial injury, or when MAP reached 30 mmHg. Survival was significantly longer in animals that transitioned into zone 1 REBOA (log-rank analysis, P = .012). The average time of survival was 14 ± 10 min for zone 3 animals vs. 65 ± 59 min for zone 1 animals (P = .064). No animals in the zone 3 group survived to the hospital phase. Zone 1-treated animals showed immediate hemodynamic improvement after transition, with maximum blood pressure reaching near baseline values compared to those in the zone 3 group. In this swine model of NCTH, hemodynamics and survival were improved when the REBOA balloon was transitioned from zone 3 to zone 1 during an impending cardiovascular collapse. Furthermore, these improved outcome data support the pursuit of additional research into mitigating ischemia-reperfusion insult to the abdominal viscera while still providing excellent resuscitative support, such as intermittent or partial REBOA.

Vascular access complications associated with resuscitative endovascular balloon occlusion of the aorta in adult trauma patients: A systematic review and meta-analysis.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is gaining popularity worldwide for managing hypotensive trauma patients. Vascular access complications related to REBOA placement have been reported, with some cases resulting in permanent morbidity. We aim to capitalize on the increase in literature to further describe and estimate the incidence of REBOA-associated vascular access complications in adult trauma patients. We searched Medline, EMBASE, Scopus, and CINAHL for studies reporting vascular access complications of REBOA in adult trauma patients from inception to October 14, 2021. Studies reporting data from adult trauma patients who underwent REBOA insertion were eligible. Exclusion criteria included patients 15 years and younger, nontrauma patients, non-REBOA use, non-vascular access complications and patient duplication. Study data was abstracted using the PRISMA checklist and verified independently by three reviewers. Meta-analysis of proportions was performed using a random effects model with Freeman-Turkey double-arcsine transformation. Post hoc meta-regression by year of publication, sheath-size, and geographic region was also performed. The incidence of vascular access complications from REBOA insertion was the primary outcome of interest. Subgroup analysis was performed by degree of bias, sheath size, technique of vascular access, provider specialty, geographical region, and publication year. Twenty-four articles were included in the systematic review and the meta-analysis, for a total of 675 trauma patients who underwent REBOA insertion. The incidence of vascular access complications was 8% (95% confidence interval, 5%-13%). In post hoc meta-regression adjusting for year of publication and geographic region, the use of a smaller (7-Fr) sheath was associated with a decreased incidence of vascular access complications (odds ratio, 0.87; 95% confidence interval, 0.75-0.99; p = 0.046; R 2 = 35%; I 2 = 48%). This study provides a benchmark for quality of care in terms of vascular access complications related to REBOA insertion in adult trauma patients. Smaller sheath size may be associated with a decrease in vascular access complications. Systematic Review and Meta-Analysis; Level III.

Use of Tranexamic Acid With Resuscitative Endovascular Balloon Occlusion of the Aorta is Associated With Higher Distal Embolism Rates: Results From the American Association of Surgery for Trauma Aortic Occlusion and Resuscitation for Trauma and Acute Care Surgery Trial.

Tranexamic acid (TXA) use has been associated with thrombotic complications. We aim to investigate outcomes associated with TXA use in the setting of high- (HP) and low-profile (LP) introducer sheaths for resuscitative endovascular balloon occlusion of the aorta (REBOA). The Aortic Occlusion and Resuscitation for Trauma and Acute Care Surgery (AORTA) database was queried for patients who underwent REBOA using a low-profile 7 French (LP) or high-profile, 11-14 French (HP) introducer sheaths between 2013 and 2022. Demographics, physiology, and outcomes were examined for patients who survived beyond the index operation. 574 patients underwent REBOA (503 LP, 71 HP); 77% were male, mean age was 44 ± 19 and mean injury severity score (ISS) was 35 ± 16. 212 patients received TXA (181 [36%] LP, 31 [43.7%] HP). There were no significant differences in admission vital signs, GCS, age, ISS, SBP at AO, CPR at AO, and duration of AO among LP and HP patients. Overall, mortality was significantly higher in the HP (67.6%) vs the LP group (54.9%; P = .043). Distal embolism was significantly higher in the HP group (20.4%) vs the LP group (3.9%; P < .001). Logistic regression demonstrated that TXA use was associated with a higher rate of distal embolism in both groups (OR = 2.92; P = .021). 2 LP patients (one who received TXA) required an amputation. Patients who undergo REBOA are profoundly injured and physiologically devastated. Tranexamic acid was associated with a higher rate of distal embolism in those who received REBOA, regardless of access sheath size. For patients receiving TXA, REBOA placement should be accompanied by strict protocols for immediate diagnosis and treatment of thrombotic complications.

Evaluation of Resuscitative Endovascular Balloon Occlusion of the Aorta Complications in a Community-Based Trauma Center.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a method of management of noncompressible torso hemorrhage in trauma patients. Increased utilization has shown increased vascular complications and mortality. This study aimed to evaluate complications of REBOA placement in a community trauma setting. A 3-year retrospective review was performed of all trauma patients that underwent REBOA placement. Data collection included demographics, injury characteristics, complications, and mortality. Twenty-three patients were included, and the overall mortality was 65.2%. Most patients suffered blunt trauma (73.9%), and median ISS and TRISS (survival probability) were 24 and 42.2%, respectively. The median time to REBOA placement was 22 minutes, and hemorrhagic control was achieved in all patients. The most common complication was acute kidney injury at 34.8%. There was one complication associated with placement that required vascular intervention but did not lead to limb amputation. Resuscitative endovascular balloon occlusion of the aorta was shown to have higher rates of acute kidney injury, similar rates of vascular injury, and lower rate of limb complications compared to published literature. Resuscitative endovascular balloon occlusion of the aorta remains a useful tool for trauma resuscitation without the fear of increased complications.

The Implementation of a Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) Program at a Level 1 New England Trauma Center: Feasibility and Early Outcomes.

We evaluated the feasibility of implementing a Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) program at our urban level 1 trauma center and evaluated early outcomes. A multidisciplinary committee including physicians (trauma surgery, emergency medicine, vascular surgery, and interventional radiology) and nurses created clinical practice guidelines for the placement of REBOA at our institution. All trauma surgeons and critical care board certified emergency medicine physicians were trained in placement and nurses received management training. A formal review process was implemented to identify areas for improvement. Finally, we instituted refresher training to maintain REBOA competency. Trauma patients with noncompressible torso hemorrhage from blunt or penetrating injuries who were partial or nonresponders to blood product resuscitation were included. Pregnant patients, children, or patients with significant hemothorax or suspected aortic or cardiac injury were excluded. Over seven months, eight catheters were successfully placed, all on the first attempt, including six in Zone 3 and two in Zone 1. All Zone 3 catheters were placed for pelvic fracture-related bleeding which were subsequently embolized. The Zone 1 catheters were placed immediately preoperatively for intraabdominal bleeding. Upon committee review, one critique was made regarding zone selection. One patient developed an arteriovenous fistula after placement which resolved without intervention. There were no other complications and all patients survived to discharge. An REBOA program is feasible and safe following a comprehensive multidisciplinary effort. The efforts described here can be utilized by similar trauma programs for adaptation of this endovascular approach to bleeding control.

Multidisciplinary Simulation of Trauma in Pregnancy with Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) Utilization.

Background Studies have demonstrated the use of resuscitative endovascular balloon occlusion catheters of the aorta (REBOA) in the setting of postpartum hemorrhage and traumatic hemorrhagic shock. However, REBOA is infrequently utilized leading to a lack of clinician comfort. This study's aim was to demonstrate the utility of REBOA in a hemorrhaging pregnant trauma patient and improve clinician comfort with the placement of REBOA while emphasizing collaboration between medical specialties. Methods A multidisciplinary in-situ simulation was developed for the management of a pregnant patient with an abdominal gunshot wound evaluated by obstetrics and surgery teams. A trauma survey, emergency c-section, massive transfusion protocol (MTP), and evaluation for and placement of REBOA were indicated during the simulation. A standardized Return on Learning questionnaire was utilized to determine participants' reactions and confidence gained during the simulation. Results A total of 32 of 41 participants completed the survey (78%). A statistically significant increase in confidence was reported in the ability toprioritize the care of a pregnant patient with hemorrhagic shock (p = 0.016), apply MTP to the appropriate clinical setting (p = 0.03), and analyze critical decisions made for abdominal trauma in pregnant patients (p = 0.006). Specifically for physicians, a significant increase in confidence in the ability to identify indications/contraindications for REBOA placement in hemorrhaging patients was observed (p = 0.021). Conclusions A multidisciplinary simulation for the management of a pregnant patient in hemorrhagic shock secondary to penetrating abdominal trauma improved learner confidence in MTP, care of pregnant patients in hemorrhagic shock, and abdominal trauma in pregnancy. Physician learners gained confidence in indications for REBOA placement in abdominal trauma. This simulation was highly relevant to all participants.

Abstract 189: Resuscitative Endovascular Balloon Occlusion Of The Aorta In The Obese Patient

Objectives: Perceptions of difficulty in obtaining arterial access in obese patients may impact the rate of resuscitative endovascular balloon occlusion of the aorta (REBOA) use in clinical practice. Excess adipose tissue can obstruct palpation of anatomic landmarks, limit sonographic visualization, and potentially increase difficulty of REBOA placement. We aimed to examine the association between obesity and REBOA placement, hypothesizing that increased body habitus would decrease success and increase time to successful aortic occlusion (AO). Methods: A retrospective analysis of the Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery (AORTA) registry was performed on REBOA patients (2013-2022). Patients with systolic blood pressure &gt; 0mmHg admission were included. Patients requiring CPR on arrival to the ED were excluded. Body mass index (BMI) categorized obesity subgroups as follows: non-obese (&lt;30), mildly obese (30-34.9), moderately obese (35-39.9), and severely obese (40+). Results: Inclusion criteria was met by 410 patients. There was no statistical difference in injury severity or admission systolic blood pressure (SBP) among the subgroups. At initiation of AO, moderately and severely obese patients had higher median SBP compared to non- and mildly obese patients (p=0.03). On multivariate analysis, BMI did not significantly impact the success of REBOA placement or time to successful AO. When stratified by arterial access technique, there was no difference in success rates, time to successful AO, or mortality between groups. Overall time to successful AO, response SBP, and mortality did not differ across subgroups. Conclusion: Following traumatic injury in obese patients, REBOA placement is a feasible intervention. Despite differences in patient body habitus, ultrasound guidance was not superior to landmark palpation for acquiring arterial access. Placement of REBOA is equally effective in obese patients and severe obesity should not impede REBOA use.

Resuscitative Endovascular Balloon Occlusion of the Aorta for Traumatic Cardiopulmonary Arrest in the Emergency Department: The First Case With Successful Return of Spontaneous Circulation in Taiwan.

Exsanguinating torso hemorrhage is a leading cause of death in trauma patients. Bleeding leads to hypothermia, acidosis, and coagulopathy, the so-called "lethal triad," and creates a vicious cycle. Therefore, bleeding control tops the priority list in the management of trauma patients. Placement of resuscitative endovascular balloon occlusion of the aorta (REBOA) in patients with traumatic non-compressible torso hemorrhage is a developing technique in the emergency departments (EDs) in Taiwan, and it is a possible solution for abdominal and pelvic trauma patients with hemodynamic instability. It not only temporarily controls bleeding below the inflation site but also increases cerebral and coronary circulation. It can create a bridge for definitive care such as an operation or an embolization, possibly preventing death. Compared to thoracotomy followed by an aortic cross clamp, REBOA is a less invasive and possibly, a more efficient way to control the hemorrhage and may lead to better overall survival. The use of REBOA has been proven to be associated with improved survival-to-discharge in severely injured trauma patients. We report a case of out-of-hospital cardiac arrest caused by penetrating injury wherein return of spontaneous circulation was successfully achieved after 39-minute cardiopulmonary resuscitation and REBOA placement in the ED. The REBOA balloon was deflated after bleeding was stopped during the laparotomy operation. The patient was then transferred to the intensive care unit for postoperative care. Unfortunately, the patient passed away approximately 12 hours after the surgery.

Comparison of aortic zones for endovascular bleeding control: age and sex differences

PurposeTo gain insight into anatomical variations between sexes and different age groups in intraluminal distances and anatomical landmarks for correct insertion of resuscitative endovascular balloon occlusion of the aorta (REBOA) without fluoroscopic confirmation.MaterialsAll non-trauma patients receiving a computed tomography angiography (CT-A) scan of the aorta, iliac bifurcation and common femoral arteries from 2017 to 2019 were eligible for inclusion.MethodsCentral luminal line distances from the common femoral artery (CFA) to the aortic occlusion zones were measured and diameters of mid zone I, II and III were registered. Anatomical landmarks and correlations were assessed. A simulated REBOA placement was performed using the Joint Trauma System Clinical Practice Guideline (JTSCPG).ResultsIn total, 250 patients were included. Central luminal line (CLL) measurements from mid CFA to aortic bifurcation (p = 0.000), CLL measurements from CFA to mid zone I, II and III (p = 0.000) and zone I length (p = 0.000) showed longer lengths in men. The length of zone I and III (p = 0.000), CLL distance measurements from the right CFA to mid zone I (p = 0.000) and II (p = 0.013) and aortic diameters measured at mid zone I, II and III increased in higher age groups (p = 0.000). Using the JTSCPG guideline, successful deployment occurred in 95/250 (38.0%) in zone III and 199/250 (79.6%) in zone I. Correlation between mid-sternum and zone I is 100%. Small volume aortic occlusion balloons (AOB) have poor occlusion rates in zone I (0–2.8%) and III (4.4–34.4%).ConclusionsMen and older age groups have longer CLL distances to zone I and III and introduction depths of AOB must be adjusted. The risk of not landing in zone III with standard introduction depths is high and balloon position for zone III REBOA is preferably confirmed using fluoroscopy. Mid-sternum can be used as a landmark in all patient groups for zone I. In older patients, balloon catheters with larger inflation volumes must be considered for aortic occlusion.

Quantifying the Cardiovascular Physiology of REBOA and Partial REBOA: How REBOA Facilitates Resuscitation but Also Strains the Left Ventricle

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is increasingly used as an endovascular approach to aortic occlusion. This can provide complete or partial aortic occlusion and is thereby known to augment afterload relative to the extent of occlusion. Despite the increasing use of this tool, little cardiovascular physiology has been quantified across clinically relevant REBOA transitions: placement of occlusive REBOA, then transition to partially occlusive REBOA, and lastly, REBOA removal. The goal of this study is to use pressure-volume loop analysis and direct left coronary artery blood flow measurements to capture these transitions in a swine model of hemorrhagic shock to elucidate the underlying physiologic mechanism of clinical REBOA use. Swine underwent complex surgical and vascular access instrumentation to capture real-time left ventricular pressure-volume loops and directly measure left coronary flow (Figure 1). Animals were hemorrhaged to 45 mmHg with subsequent placement of fully occlusive REBOA, followed by transition to partial REBOA while these data were captured. A full methodological protocol has been published: https://doi.org/10.21203/rs.3.pex-1646/v1. Five male swine underwent this protocol (mean weight, 53.6 ± 3.6 kg). Hemorrhagic shock was induced and maintained with reduction of stroke work (baseline: 3.1 L × mmHg vs shock: 1.2 L × mmHg; P < .01) and average end systolic pressure (109.8 vs 59.6 mmHg; P = .02). REBOA augmented the end systolic pressure volume relationship. Stroke work evolved with placement of occlusive REBOA (1.2 vs 4.3 mmHgL; P < .01). End systolic elastance was augmented from baseline by shock and REBOA placement (1.01 vs 0.39 vs 4.50 mL/mmHg; P < .01) and remained elevated with transition to partial REBOA (3.22 mL/mmHg) (Figure 2). Percent time in antegrade coronary blood flow decreased during shock (94% to 71.8%; P < .01) and was rescued with REBOA, but REBOA also increased peak coronary flow compared with shock (271 vs 93 mL/min; P < .01) and total coronary flow, even beyond baseline (peak: 2136 vs baseline: 424 mL/min; P < .01). No REBOA state augmented the end diastolic pressure volume relationship. REBOA maintains the end diastolic pressure volume relationship, but increases afterload, thereby augmenting the end systolic pressure volume relationship and left ventricle contractility with partial REBOA. REBOA alters coronary artery blood flow by reversing shock-induced retrograde coronary flow, and increasing peak coronary artery flow, therefore increasing total flow. The afterload modulation from REBOA underlies its resuscitative capability but may drive the mechanism of cardiovascular injury. Partial REBOA with resuscitation balances the afterload improvement against undue left ventricle strain.Fig 2End systolic elastance (Ees; the slope of the end systolic pressure volume relationship) evolution across study periods. *P = .003; **P = .048; ***P = .01; ****P = .015.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

The Underlying Cardiovascular Mechanisms of Resuscitation and Injury of REBOA and Partial REBOA.

Introduction: Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) is used for aortic control in hemorrhagic shock despite little quantification of its mechanism of resuscitation or cardiac injury. The goal of this study was to use pressure-volume (PV) loop analysis and direct coronary blood flow measurements to describe the physiologic changes associated with the clinical use of REBOA. Methods: Swine underwent surgical and vascular access to measure left ventricular PV loops and left coronary flow in hemorrhagic shock and subsequent placement of occlusive REBOA, partial REBOA, and no REBOA. PV loop characteristics and coronary flow are compared graphically with PV loops and coronary waveforms, and quantitatively with measures of the end systolic and end pressure volume relationship, and coronary flow parameters, with accounting for multiple comparisons. Results: Hemorrhagic shock was induced in five male swine (mean 53.6 ± 3.6 kg) as demonstrated by reduction of stroke work (baseline: 3.1 vs. shock: 1.2 L*mmHg, p < 0.01) and end systolic pressure (ESP; 109.8 vs. 59.6 mmHg, p < 0.01). ESP increased with full REBOA (178.4 mmHg; p < 0.01), but only moderately with partial REBOA (103.0 mmHg, p < 0.01 compared to shock). End systolic elastance was augmented from baseline to shock (1.01 vs. 0.39 ml/mmHg, p < 0.01) as well as shock compared to REBOA (4.50 ml/mmHg, p < 0.01) and partial REBOA (3.22 ml/mmHg, p = 0.01). Percent time in antegrade coronary flow decreased in shock (94%–71.8%, p < 0.01) but was rescued with REBOA. Peak flow increased with REBOA (271 vs. shock: 93 ml/min, p < 0.01) as did total flow (peak: 2136, baseline: 424 ml/min, p < 0.01). REBOA did not augment the end diastolic pressure volume relationship. Conclusion: REBOA increases afterload to facilitate resuscitation, but the penalty is supraphysiologic coronary flows and imposed increase in LV contractility to maintain cardiac output. Partial REBOA balances the increased afterload with improved aortic system compliance to prevent injury.

Increased mortality with resuscitative endovascular balloon occlusion of the aorta only mitigated by strong unmeasured confounding: An expanded analysis using the National Trauma Data Bank.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is being increasingly adopted to manage noncompressible torso hemorrhage, but a recent analysis of the 2015 to 2016 Trauma Quality Improvement Project (TQIP) data set showed that placement of REBOA was associated with higher rates of death, lower extremity amputation, and acute kidney injury (AKI). We expand this analysis by including the 2017 data set, quantifying the potential role of residual confounding, and distinguishing between traumatic and ischemic lower extremity amputation. This retrospective study used the 2015 to 2017 TQIP database and included patients older than 18 years, with signs of life on arrival, who had no aortic injury and were not transferred. Resuscitative endovascular balloon occlusions of the aorta placed after 2 hours were excluded. We adjusted for baseline variables using propensity scores with inverse probability of treatment weighting. A sensitivity analysis was then conducted to determine the strength of an unmeasured confounder (e.g., unmeasured shock severity/response to resuscitation) that could explain the effect on mortality. Finally, lower extremity injury patterns of patients undergoing REBOA were inspected to distinguish amputation indicated for traumatic injury from complications of REBOA placement. Of 1,392,482 patients meeting the inclusion criteria, 187 underwent REBOA. After inverse probability of treatment weighting, all covariates were balanced. The risk difference for mortality was 0.21 (0.14-0.29) and for AKI was 0.041 (-0.007 to 0.089). For the mortality effect to be explained by an unmeasured confounder, it would need to be stronger than any observed in terms of its relationship with mortality and with REBOA placement. Eleven REBOA patients underwent lower extremity amputation; however, they all suffered severe traumatic injury to the lower extremity. There is no evidence in the TQIP data set to suggest that REBOA causes amputation, and the evidence for its effect on AKI is considerably weaker than previously reported. The increased mortality effect of REBOA is confirmed and could only be nullified by a potent confounder. Therapeutic/care management, level IV.