Circulation - Hemorrhage Control

#### HEMORRHAGE CONTROL

J Spec Oper Med. 2018 Fall;18(3):39-44.

# Worldwide case reports using the iTClamp for external hemorrhage control.

McKee J, Kirkpatrick A, Bennett B, Jenkins D, Logsetty S, Holcomb J

BACKGROUND: Historically, hemorrhage control strategies consisted of manual pressure, pressure dressings, gauze with or without hemostatic ingredients for wound packing, or the use of tourniquets. The iTClamp is a relatively new alternative to stop external bleeding.

METHODS: An anonymous survey was used to evaluate the outcomes of the iTClamp in worldwide cases of external bleeding.

RESULTS: A total of 245 evaluable applications were reported. The iTClamp stopped the bleeding in 81% (n = 198) of the cases. Inadequate bleeding control was documented in 8% (n = 20) and in the remaining 11% (n = 27), bleeding control was not reported. The top three anatomic body regions for iTClamp application were the scalp, 37% (n = 91); arm, 20% (n = 49); and leg, 19% (n = 46). In 26% of the reported cases (direct pressure [23% (n = 63)] and tourniquets [3% (n = 8]), other techniques were abandoned in favor of the iTClamp. Conversely, the iTClamp was abandoned in favor of direct pressure 11 times (4.4%) and abandoned in favor of a tourniquet three times (1%).

CONCLUSION: The iTClamp appears to be a fast and reliable device to stop external bleeding. Because of its function and possible applications, it has potential to lessen the gap between and add to the present selection of devices for treatment of external bleeding.

#### PELVIC IMMOBILIZATION / HEMORRHAGE

J Trauma Acute Care Surg. 2018 Jun;84(6):924-928

# The focused abdominal sonography for trauma examination can reliably patients with significant intra-abdominal hemorrhage in life-threatening pelvic fractures.

Christian N, Burlew C, Moore E, Geddes A, Wagenaar A, Fox C, Pieracci F

BACKGROUND: The focused abdominal sonography for trauma (FAST) examination has been reported to be unreliable in pelvic fracture patients. Additionally, given the advent of new therapeutic interventions, such as resuscitative endovascular balloon occlusion of the aorta (REBOA), rapid identification of intra-abdominal hemorrhage compared with Zone III hemorrhage may guide different therapeutic strategies. We hypothesized that FAST is reliable for detecting clinically significant intra-abdominal hemorrhage in the face of complex pelvic fractures.

METHODS: Our pelvic fracture database of all hemodynamically unstable patients requiring intervention from January 1, 2005, to July 1, 2015, was reviewed. The FAST examination was compared with operative and computed tomography (CT) scan findings. Confirmatory evaluation for FAST(-) patients was considered positive if therapeutic intervention was required.

RESULTS: During the study period, 81 patients in refractory shock with FAST imaging in our emergency department (ED) underwent pelvic packing. Mean age was 45 ± 2 years and Injury Severity Score was 50 ± 1.5. The FAST examination was negative in 53 patients; 52 patients did not require operative intervention for abdominal bleeding while one patient required splenectomy. The FAST examination was positive in 28 patients; 26 had findings confirmed by CT or laparotomy while two patients did not have intra-abdominal hemorrhage on further evaluation. The sensitivity and specificity for FAST in this population was 96% and 96%, respectively, positive predictive value was 93%, and negative predictive value was 98%. The false-negative and -positive rates for FAST were 2% and 7%.

CONCLUSION: Focused abdominal sonography for trauma examination reliably identifies clinically significant hemoperitoneum in life-threatening, pelvic fracture related hemorrhage. The incidence of a false-negative FAST in this unstable pelvic fracture population was 2%. FAST results may be used when determining the role of REBOA in these multisystem trauma patients and requires further study. REBOA placement should be considered in hemodynamically unstable pelvic fracture patients who are FAST(-), while laparotomy should be used in FAST(+) patients.

LEVEL OF EVIDENCE: Therapeutic, level IV.

Injury. 2018 Aug;49(8):1568-1571

# The pelvic factures- indicator of injury severity or lethal fracture?

Holtenius J, Bakhshayesh P, Enocson A

BACKGROUND: Presence of pelvic fractures in trauma patients has previously been related to high mortality. However, there are controversies on whether pelvic fractures are the underlying cause of death or if it is rather an indicator of injury severity. We aimed to assess whether the presence of pelvic fracture increased mortality among a cohort of trauma patients or if it was simply an indicator of severe injury.

MATERIAL AND METHODS: Karolinska University Hospital is the largest trauma centre in Sweden. The hospital is linked to the Swedish National Trauma Registry, "SweTrau". Registry data was collected for the period January 2013 until December 2015 with a one year further follow-up regarding mortality. Patients in the pelvic fracture group were compared to the non-pelvic fracture group and regression analysis was performed adjusting for factors that could possibly affect mortality.

RESULTS: Univariable analysis showed that pelvic fracture was associated with an increased mortality, OR 2.4 (CI 1.3-3.4). Multivariable analysis showed that the presence of a pelvic fracture was not associated with an increased 30-day mortality (OR 0.5, CI 0.2-0.9), while factors as Shock (OR 7.1, CI 4.6-10.9), GCS < 9 (OR 6.2, CI 3.9-9.8), ISS > 15 (OR 12.4, CI 8.1-18.9), Age >60 (OR 3.2, CI 2.1-4,9) and ASA 3-4 (OR 4.7, CI 3.1-7.3) were associated with an increased 30-day mortality. Factors affecting 1-year mortality was analysed in the same way and the results were similar.

CONCLUSION: Presence of pelvic fractures in trauma patients is not correlated to increased mortality when adjusted for Age, ISS, ASA, GCS and Shock.

#### ADVANCED HEMORRHAGE CONTROL

J Trauma Acute Care Surg. 2018 Jul;85(1):25-32

# Mobile forward-looking infrared technology allows rapid assessment of resuscitative endovascular balloon occlusion of the aorta in hemorrhage and blackout conditions.

Barron M, Kuckelman J, McClellan J, Derickson M, Phillips C, Marko S, Sokol K, Eckert M, Martin M.

INTRODUCTION: Objective assessment of final resuscitative endovascular balloon occlusion of the aorta (REBOA) position and adequate distal aortic occlusion is critical in patients with hemorrhagic shock, especially as feasibility is being increasingly investigated in the prehospital setting. We propose that mobile forward-looking infrared (FLIR) thermal imaging is a fast, reliable, and noninvasive method to assess REBOA position and efficacy in scenarios applicable to battlefield and prehospital care.

METHODS: Ten swine were randomized to a 40% hemorrhage group (H, n = 5) or nonhemorrhage group (NH, n = 5). Three experiments were completed after Zone I placement of a REBOA catheter. Resuscitative endovascular balloon occlusion of the aorta was deployed for 30 minutes in all animals followed by randomized continued deployment versus sham in both light and blackout conditions. Forward-looking infrared images and hemodynamic data were obtained. Images were presented to 62 blinded observers for assessment of REBOA inflation status.

RESULTS: There was no difference in hemodynamic or laboratory values at baseline. The H group was significantly more hypotensive (mean arterial pressure 44 vs. 60 mm Hg, p < 0.01), vasodilated (systemic vascular resistance 634 vs. 938dyn·s/cm, p = 0.02), and anemic (hematocrit 12 vs. 23.2%, p < 0.01). Hemorrhage group animals remained more hypotensive, anemic, and acidotic throughout all three experiments. There was a significant difference in the temperature change (ΔTemp) measured by FLIR between animals with REBOA inflated versus not inflated (5.7°C vs. 0.7°C, p < 0.01). The H and NH animals exhibited equal magnitudes of ΔTemp in both inflated and deflated states. Blinded observer analysis of FLIR images correctly identified adequate REBOA inflation and aortic occlusion 95.4% at 5 minutes and 98.8% at 10 minutes (positive predictive value at 5 minutes = 99% and positive predictive value at 10 minutes = 100%).

CONCLUSIONS: Mobile thermal imaging is an easy, rapid, and reliable method for assessing distal perfusion after occlusion by REBOA. Smartphone-based FLIR technology allows for confirmation of adequate REBOA placement at the point of care, and performance was not degraded in the setting of major hemorrhage or blackout conditions.

J Spec Oper Med. Summer 2018;18(2):98-104.

# Methods for Early Control of Abdominal Hemorrhage: An Assessment of Potential Benefit.

Cantle P, Hurley M, Swartz M, Holcomb J

BACKGROUND: Noncompressible truncal hemorrhage (NCTH) after injury is associated with a mortality increase that is unchanged during the past 20 years. Current treatment consists of rapid transport and emergent intervention. Three early hemorrhage control interventions that may improve survival are placement of a resuscitative endovascular balloon occlusion of the aorta (REBOA), injection of intracavitary self-expanding foam, and application of the Abdominal Aortic Junctional Tourniquet (AAJT™). The goal of this work was to ascertain whether patients with uncontrolled abdominal or pelvic hemorrhage might benefit by the early or prehospital use of one of these interventions.

METHODS: This was a single-center retrospective study of patients who received a trauma laparotomy from 2013 to 2015. Operative reports were reviewed. The probable benefit of each hemorrhage control method was evaluated for each patient based on the location(s) of injury and the severity of their physiologic derangement. The potential scope of applicability of each control method was then directly compared.

RESULTS: During the study period, 9,608 patients were admitted; 402 patients required an emergent trauma laparotomy. REBOA was potentially beneficial for hemorrhage control in 384 (96%) of patients, foam in 351 (87%), and AAJT in 35 (9%). There was no statistically significant difference in the potential scope of applicability between REBOA and foam (ρ = .022). There was a significant difference between REBOA and AAJT (ρ < .001) and foam and AAJT™ (ρ < .001). The external surface location of signs of injury did not correlate with the internal injury location identified during laparotomy.

CONCLUSION: Early use of REBOA and foam potentially benefits the largest number of patients with abdominal or pelvic bleeding and may have widespread applicability for patients in the preoperative, and potentially the prehospital, setting. AAJT may be useful with specific types of injury. The site of bleeding must be considered before the use of any of these tools.

Crit Care. 2018 Jun 18;22(1):164.

# Early fibrinogen concentrate therapy for major haemorrhage in trauma (E-FIT 1): results from a UK multi-centre, randomised, double blind, placebo-controlled pilot trial.

Curry N, Foley C, Wong H, Mora A, Curnow E, Zarankaite A, Hodge R, Hopkins V, Deary A, Ray J, Moss P, Reed M, Kellett S, Davenport R, Stanworth S

BACKGROUND: There is increasing interest in the timely administration of concentrated sources of fibrinogen to patients with major traumatic bleeding. Following evaluation of early cryoprecipitate in the CRYOSTAT 1 trial, we explored the use of fibrinogen concentrate, which may have advantages of more rapid administration in acute haemorrhage. The aims of this pragmatic study were to assess the feasibility of fibrinogen concentrate administration within 45 minutes of hospital admission and to quantify efficacy in maintaining fibrinogen levels ≥ 2 g/L during active haemorrhage.

METHODS: We conducted a blinded, randomised, placebo-controlled trial at five UK major trauma centres with adult trauma patients with active bleeding who required activation of the major haemorrhage protocol. Participants were randomised to standard major haemorrhage therapy plus 6 g of fibrinogen concentrate or placebo.

RESULTS: Twenty-seven of 39 participants (69%; 95% CI, 52-83%) across both arms received the study intervention within 45 minutes of admission. There was some evidence of a difference in the proportion of participants with fibrinogen levels ≥ 2 g/L between arms (p = 0.10). Fibrinogen levels in the fibrinogen concentrate (FgC) arm rose by a mean of 0.9 g/L (SD, 0.5) compared with a reduction of 0.2 g/L (SD, 0.5) in the placebo arm and were significantly higher in the FgC arm (p < 0.0001) at 2 hours. Fibrinogen levels were not different at day 7. Transfusion use and thromboembolic events were similar between arms. All-cause mortality at 28 days was 35.5% (95% CI, 23.8-50.8%) overall, with no difference between arms.

CONCLUSIONS: In this trial, early delivery of fibrinogen concentrate within 45 minutes of admission was not feasible. Although evidence points to a key role for fibrinogen in the treatment of major bleeding, researchers need to recognise the challenges of timely delivery in the emergency setting. Future studies must explore barriers to rapid fibrinogen therapy, focusing on methods to reduce time to randomisation, using 'off-the-shelf' fibrinogen therapies (such as extended shelf-life cryoprecipitate held in the emergency department or fibrinogen concentrates with very rapid reconstitution times) and limiting the need for coagulation test-based transfusion triggers.

TRIAL REGISTRATION: ISRCTN67540073 . Registered on 5 August 2015.

J Trauma Acute Care Surg. 2018 Jun;84(6):917-923

# Intravenous administration of synthetic of platelets (SynthoPlate) in a mouse liver injury model of uncontrolled hemorrhage improves hemostasis.

Dyer M, Hickman D, Luc N, Haldeman S, Loughran P, Pawlowski C, Sen Gupta A, Neal M

BACKGROUND: Clinical resuscitative treatment of traumatic hemorrhage involves transfusion of RBC, platelets and plasma in controlled ratios. However, use of such blood components, especially platelets, present many challenges including availability, portability, contamination risks, and short shelf-life, which limit the use of platelet transfusions outside of large trauma centers such as remote civilian hospitals and austere prehospital settings. This has prompted significant research in platelet substitutes that may resolve the above issues while providing platelet-mimetic hemostatic action. In this framework, we have developed a synthetic platelet surrogate, SynthoPlate, by integrative decoration of platelet function mimetic peptides on a biocompatible lipid nanovesicle platform. We have previously demonstrated hemostatic capability of SynthoPlate in correcting tail-bleeding time in thrombocytopenic mice. Building on this, we hypothesized that SynthoPlate transfusion would decrease bleeding in a murine model of acute hemorrhagic shock.

METHODS: A validated model of uncontrolled intraperitoneal hemorrhage, via liver laceration was used to induce hemorrhagic shock in mice. SynthoPlate, control (unmodified) particles, and normal saline were administered as pretreatment and recue infusions to mice undergoing liver laceration and evaluated for hemostatic benefit by determining differences in blood loss and monitoring real-time hemodynamic data.

RESULTS: Pretreatment SynthoPlate transfusion resulted in significant reduction of blood loss following hemorrhage, compared with control particles or normal saline treatment (0.86 ± 0.16 g control particles [CP] vs. 0.84 ± 0.13 g normal saline [NS] vs. 0.68 ± 0.09 g SynthoPlate, p < 0.005). SynthoPlate transfused mice demonstrated improved hemodynamics taking significantly longer to develop post-injury hypotension (168.3 ± 106.6 seconds CP vs. 137 ± 58 seconds NS vs. 546.7 ± 329.8 seconds SynthoPlate, p < 0.05). SynthoPlate infusion following liver laceration, that is, rescue transfusion, also resulted in a significant decrease in blood loss (0.89 ± 0.17 g CP vs. 0.92 ± 0.19 g NS vs. 0.69 ± 0.18 g SynthoPlate, p < 0.05).

CONCLUSION: Transfusion of SynthoPlate particles reduces blood loss in a murine model of liver injury, and SynthoPlates may represent a viable transfusion product for the mitigation of blood loss in acute, severe hemorrhagic shock.

Ann Emerg Med 2018;71:A17-A20

# Who should perform REBOA technique?

Greene J

An endovascular procedure developed in the field by military physicians desperate to find new ways to stop traumatic bleeding is being welcomed by civilian trauma centers, but it is also prompting difficult questions about which medical specialties should perform it. An American College of Surgeons Committee on Trauma (ACS COT) and American College of Emergency Physicians (ACEP) joint guideline requiring that emergency physicians have “added critical care certification” to perform the procedure inspired a rapid backlash that led ACEP to convene a working group to “rework the language.”

J Trauma Acute Care Surg. 2018 May 2. doi: 10.1097/TA.0000000000001964. [Epub ahead of print]

# Extending the golden hour for Zone 1 REBOA: improved survival and reperfusion injury with intermittent versus continuous REBOA in a porcine severe truncal hemorrhage model.

Kuckelman J, Barron M, Moe D, Derickson M, Phillips C, Kononchik J, Lallemand M, Marko S, Eckert M, Martin M

BACKGROUND: Non-compressible hemorrhage can be controlled using resuscitative endovascular occlusion of the aorta (REBOA). Prolonged ischemia limits REBOA application during Zone 1 deployment. Intermittent inflation/deflation may effectively mitigate this problem.

METHODS: A lethal abdominal vascular injury was created in 28 swine. Animals were randomized to controls (n=7), 60min full REBOA (FR, n=5), time-based intermittent REBOA (iRT, n=7), and pressure-based REBOA (iRP, n=9). Intermittent groups had an initial inflation for 15min, followed by 10min inflation: 3min deflation cycles (iRT) or an inflate/deflate schedule based on blood pressure (MAP)<40mmHg (iRP). Experiments were concluded after 120min or death (MAP<20mmHg).

RESULTS: Intermittent REBOA animals all survived to 120min versus 15min for controls and 63min for FR(p<0.001). After 60min, FR animals were more hypotensive(MAP 20mmHg vs 80mmHg(iRP) and 100mmHg(iRT), p<0.001), had lower cardiac output(1.06mL/min vs 5.1L/min(iRP) and 8.2L/min(iRT), p<0.001), higher lactate(12.5mg/dL vs 8.5mg/dL(iRP), p=0.02), and decreased clot firmness on ROTEM than iRP/T(64mm vs 69mm(iRP) and 69mm(iRT), p=0.04). Acidosis was worse in iRT versus iRP at 120min (pH 7.28 vs 7.12, p=0.02), improved lactate (11.9mg/dL vs 16.3mg/dL, p=0.04), and decreased whole blood resuscitation (452cc vs 646cc, p=0.05). Blood loss (clot weight) was higher in controls (2.0kg) versus iRT and iRP(1.16kg and 1.23kg, p<0.01) and not different from FR(0.87kg, p=0.10).

CONCLUSION: Intermittent REBOA can maintain supraceliac hemorrhage control while decreasing distal ischemia in a swine model. Prolonged survival times, decreased acidosis, and lower resuscitation requirements indicate that this technique could potentially extend Zone 1 REBOA deployment times. Schedules based on MAP may be superior to time-based regimens.

LEVEL OF EVIDENCE: Not applicable as an animal study.

STUDY DESIGN: Original article.

J Trauma Acute Care Surg. 2018 Sep;85(3):626-634

# A meta-analysis of the incidence of complications associated with groin access after the use of resuscitative endovascular balloon occlusion of the aorta in trauma patients.

Manzano-Nunez R, Orlas C, Herrera-Escobar J, Galvagno S, DuBose J, Melendez J, Serna JJ Salcedo A, Peña C, Angamarca E, Horer T, Salazar C, Lopez-Castilla V, Ruiz-Yucuma J, Rodriguez F, Parra M, Ordoñez C

BACKGROUND: Serious complications related to groin access have been reported with the use of resuscitative endovascular balloon occlusion of the aorta (REBOA). We performed a systematic review and meta-analysis to estimate the incidence of complications related to groin access from the use of REBOA in adult trauma patients.

METHODS: We identified articles in MEDLINE and EMBASE. We reviewed all studies that involved adult trauma patients who underwent the placement of a REBOA and included only those that reported the incidence of complications related to groin access. A meta-analysis of proportions was performed.

RESULTS: We identified 13 studies with a total of 424 patients. REBOA was inserted most commonly by trauma surgeons or emergency room physicians. Information regarding puncture technique was reported in 12 studies and was available for a total of 414 patients. Percutaneous access and surgical cutdown were performed in 304 (73.4%) and 110 (26.5%) patients, respectively. Overall, complications related to groin access occurred in 5.6% of patients (n = 24/424). Lower limb amputation was required in 2.1% of patients (9/424), of which three cases (3/424 [0.7%]) were directly related to the vascular puncture from the REBOA insertion. A meta-analysis that used the logit transformation showed a 5% (95% CI 3%-9%) incidence of complications without significant heterogeneity (LR test: χ = 0.73, p = 0.2, Tau-square = 0.2). In a second meta-analysis, we used the Freeman-Tukey double arcsine transformation and found an incidence of complications of 4% (95% CI 2%-7%) with low heterogeneity (I = 16.3%).

CONCLUSION: We found that the incidence of complications related to groin access was of 4-5% based on a meta-analysis of 13 studies published worldwide. Currently, there are no benchmarks or quality measures as a reference to compare, and thus, further work is required to identify these benchmarks and improve the practice of REBOA in trauma surgery.

LEVEL OF EVIDENCE: Systematic review and meta-analysis, level III.

J Trauma Acute Care Surg. 2018 Sep;85(3):507-511

# Early arterial access for REBOA is related to survival outcome in trauma.

Matsumura Y, Matsumoto J, Kondo H, Idoguchi K, Ishida T, Okada Y, Kon Y, OkanK, Ishida K, Toyoda Y, Funabiki T; DIRECT-IABO Investigators.

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been used in refractory hemorrhagic shock patients. Since the optimal timing of arterial access remains unclear, we evaluated the preocclusion status of patients, and elapsed time from the arrival to the hospital is associated with the survival outcomes in the REBOA patients.

METHODS: From August 2011 to December 2016, The Diagnostic and Interventional Radiology in Emergency, Critical care and Trauma-Intra-Aortic Balloon Occlusion (DIRECT-IABO) investigators registered refractory hemorrhagic shock patients undergoing REBOA from 23 hospitals in Japan. Patient characteristics, mechanism of injury, Injury Severity Score (ISS), preocclusion and postocclusion systolic blood pressure, duration of aortic occlusion, clinical time course, and survival outcome were recorded and analyzed. Binary logistic regression analysis was used with mortality and Kaplan-Meier survival analysis was conducted to demonstrate the difference between early and delayed access groups.

RESULTS: Among the enrolled 207 cases, the following patients were excluded from the analysis: five since they were younger than 18 years, nine due to failed attempts at REBOA, 51 nontrauma patients, and 33 who received resuscitative thoracotomy plus REBOA. Thus, the remaining 109 cases were analyzed (30-day survivors, n = 60; nonsurvivors, n = 49). The preocclusion systolic blood pressure was higher, and both hospital arrival to initial arterial access and duration of occlusion were shorter in the survivors. Lower ISS (odds ratio, 0.944; 95% confidence interval, 0.907-0.982; p = 0.0039) and shorter arrival to access (odds ratio, 0.989; 95% confidence interval, 0.979-0.999; p = 0.034) were significantly associated with 30-day survival in the logistic regression analysis. The cutoff point of 21.5 minutes was used in the receiver operating characteristic analysis. The early access group showed a significantly shorter time of arrival to definitive hemostasis and also demonstrated a significantly higher survival in the Kaplan-Meier survival analysis (p = 0.014, Log-rank test).

CONCLUSION: The arrival to access time and ISS were significantly associated with mortality in the REBOA patients in Japan. The early access group demonstrated better survival. The proactive early access in the resuscitation phase might be related to better patient outcomes.

LEVEL OF EVIDENCE: Therapeutic/care management, level V.

J Trauma Acute Care Surg. 2018 Jul;85(1S Suppl 2):S98-S103

# Recent advances in austere combat surgery: use of aortic balloon occlusion as well as blood challenges by special operations medical forces in recent combat operations.

Northern D, Manley J, Lyon R, Farber D, Mitchell B, Filak K, Lundy J, DuBose J, Rasmussen T, Holcomb J

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) for control of noncompressible torso hemorrhage is a technology that is increasingly being utilized in the combat casualty setting. Its use in the resource restricted environment holds potential to improve hemorrhage control, decrease blood product utilization, decrease morbidity, and improve combat mortality. The objective of this report is to present the single largest series of REBOA use on severely injured combat casualties.

METHODS: Over an 18-month period, austere surgical teams comprised of coalition partners provided initial damage control resuscitation (DCR) and surgical stabilization for over 2,300 combat casualties prior to transferring patients to the next level of trauma care.

RESULTS: Twenty patients presented with injuries from explosion and gunshot wounds with mean initial heart rate of 129 bpm and mean initial systolic blood pressure of 71 mm Hg. Femoral cut downs were used in six patients. Aortic occlusion was achieved with REBOA catheter placement in Zone 1 (n = 17) and Zone 3 (n = 2). Systolic blood pressure increased an average of 56 mm Hg with aortic occlusion. There were no access related site complications. All patients survived transport to the next level of care. The majority of blood products transfused in this cohort were whole blood, largely supported by emergent blood drives.

CONCLUSION: This series demonstrates the potential for REBOA as a lifesaving technique for the patient who presents with hemodynamic instability and noncompressible torso hemorrhage. Resuscitative endovascular balloon occlusion of the aorta allows austere surgical teams to rapidly stabilize severely injured combat casualties, expand capability, and provide enhanced DCR while minimizing personnel, resources, and blood product utilization. The use of "whole blood only" strategy for DCR shows potential to be superior to traditional component therapy, and when combined with "proactive" REBOA utilization, provides significant improvements in hemodynamics and hemorrhage control.

LEVEL OF EVIDENCE: Case series, level V.

Ann Emerg Med. 2018 Aug;72(2):225-226

# Breaking down silos: the joint statement about the clinical use of resuscitative endovascular balloon occlusion of the aorta (REBOA) warrants revision.

Qasim Z, DuBose J, Rasmussen T, Teeter W

Brenner et al recently published a joint statement between the American College of Surgeons Committee on Trauma and the American College of Emergency Physicians on the clinical use of resuscitative endovascular balloon occlusion of the aorta (REBOA). The statement created concern in both civilian and military communities by its—in our opinion—overly restrictive message and notable omissions.

J Surg Res. 2018 Jun;226:31-39

# Comparison of zone 3 resuscitative endovascular balloon occlusion of the aorta and the abdominal aortic and junctional tourniquet in a model of junctional hemorrhage in swine.

Rall J, Redman T, Ross E, Morrison J, Maddry J

BACKGROUND: Traumatic injuries to the pelvis and high junctional injuries are difficult to treat in the field; however, Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) and the Abdominal Aortic and Junctional Tourniquet (AAJT) constitute two promising treatment modalities. The aim of this study is to use a large animal model of pelvic hemorrhage to compare the survival, hemostatic, hemodynamic, and metabolic profile of both techniques.

METHODS: Yorkshire swine (n = 10, 70-90 kg) underwent general anesthesia, instrumentation, and surgical isolation of the femoral artery. Uncontrolled hemorrhage was initiated by an arteriotomy. Animals were randomly allocated to either REBOA or AAJT. Following completion of device application, both groups received a 500 mL Hextend bolus. After 1 hour, the injured femoral artery wasligated to simulate definitive hemostasis followed by a second Hextend bolus and device removal. Animals were observed for two more hours. Physiological data were collected throughout the experiments and compared between groups.

RESULTS: Both techniques achieved 100% hemostasis, and all animals survived the entire experiment except one in the REBOA group. During the hour treatment phase, the AAJT group had a higher mean arterial pressure than the REBOA group (59.9 ± 16.1 versus 44.6 ± 9.8 mm Hg, respectively; P < 0.05). The AAJT-treated group had higher lactate levels than the REBOA-treated group (4.5 ± 2.0 versus 3.2 ± 1.3 mg/dL, respectively; P < 0.05).

CONCLUSIONS: Despite their mechanistic differences, both techniques achieved a similar hemostatic, hemodynamic, and metabolic profile. Some differences do exist including lactate levels and blood pressure.

J Trauma Acute Care Surg. 2018 Jun 12. doi: 10.1097/TA.0000000000002003. [Epub ahead of print]

# No wire? No Problem: resuscitative endovascular balloon occlusion of the aorta (REBOA) can be performed effectively and more rapidly with a wire-free device.

Romagnoli A, Teeter W, Wasicek P, Gamble W, Hu F, Stein D, Scalea T, Brenner M

INTRODUCTION: A wire-free device is available for REBOA providing aortic occlusion (AO) without lengthy platform guide-wires and large sheaths.

METHODS: This was a retrospective, single-institution review of patients who received REBOA from May 2014-September 2017. Timing of procedural steps was measured in seconds (s) using time-stamped videography.

RESULTS: 74 patients received REBOA; 29 with a platform guidewire, 12F sheath, and balloon catheter (W group), and 45 with a 7F sheath and wire-free device (WF group). Mean age (p=0.22) and ISS (p=0.80) were similar between groups. 59 patients received REBOA at Zone 1; 15 patients at Zone 3. There was no difference in median [IQR] time to common femoral artery (CFA) access between the WF (194[98,313]s) and W (193[126,280]s) groups (p=0.96). Both median time to AO after CFA access (WF:158[109,264]s vs. W:307[222,390]s, p<0.001) and median total procedural time (WF:366[263,596]s vs. W:511[441,597]s; p=0.012) were significantly shorter with the wire-free system. The rates of percutaneous versus open CFA access was not different between groups (p=0.48). Both groups had a similar physiologic response to AO as measured by pre- and post-AO SBP (p=0.86). Overall mortality rate was 74%; 90% in the W group, and 64% in the WF group (p = 0.027). The procedure-related complication rate was not significantly different between groups with regard to compartment syndrome (W:3% vs WF:4%, p=1.0), access-related complications (W:0 vs WF:6%, p=0.28) or systemic complication (W:0 vs WF:9%, p=0.15).

CONCLUSIONS: Once CFA access is obtained, AO with a smaller wire-free device reduces procedural time by approximately 50%. When perfusion to proximal organs is essential, the seconds saved to achieve AO may contribute to improved mortality. Time to obtain CFA access is not dependent on introducer sheath size.

LEVEL OF EVIDENCE: Therapeutic, Level V.

Mil Med. 2018 Jan 1;183(1-2):e45-e50

# Fibrinogen concentrates in the Special Operations Forces environment.

Sanders S, Tien H, Callum J, Nascimento B, Peng H, Funk C, Schmid J, Rizoli S, Rhind S, Beckett A

Introduction: Hemorrhage is the most common cause of death among Special Operations Force (SOF) soldiers. Bringing remote damage control resuscitation into the far-forward combat environment is logistically challenging, as it requires blood products that generally require a robust cold chain. Alternatively, lyophilized products such as fibrinogen concentrate, which does not require thawing or blood group compatibility testing before use, might be advantageous in damage control resuscitation in the battlefield. In this report, we review the evidence for the use of fibrinogen concentrate in the Canadian SOF environment.

Materials and Methods: The literature on the use of fibrinogen concentrate in the trauma setting was reviewed by Canadian Forces Services Working Group, in three separate meetings. Multiple stakeholders were consulted to obtain authoritative perspectives from subject matter experts on the use of fibrinogen concentrate in the Canadian SOF environment. We also conducted a comparison review of fibrinogen content, pathogen risk, shelf life, and methods required for use for fresh frozen plasma, cryoprecipitate, and fibrinogen concentrate relevant to their application in the far-forward combat environment.

Results: Indications and a protocol for the use of fibrinogen as an adjunct to fresh whole blood were formulated based on a literature review and clinical expert opinion. Alternative strategies and other lyophilized blood products were considered before selecting fibrinogen concentrate as the lyophilized blood product of choice. Fibrinogen concentrate is an ABO-universal blood product with an excellent safety profile. Training was conducted by subject matter experts within civilian trauma centers and at military training facilities. The clinical efficacy and safety were confirmed by monitoring the use of fibrinogen concentrate in deployed combat settings.

Conclusion: Fibrinogen concentrate is a useful adjunct to remote damage control resuscitation in the SOF environment. Fibrinogen concentrate was found to be robust for transport into the SOF environment and is widely accepted among SOF operators and medics.

J Trauma Acute Care Surg. 2018 Jul;85(1):101-10

# Location is everything: the hemodynamic effects of REBOA in Zone 1 versus Zone 3 of the aorta.

Tibbits E, Hoareau G, Simon M, Davidson A, DeSoucy E, Faulconer E, DuBose J, Neff L, Grayson J, Williams T, Johnson M

OBJECTIVES: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emerging technology to augment proximal blood pressure during the resuscitation of patients with noncompressible torso hemorrhage. Currently, placement choice, supraceliac (Zone 1) versus infrarenal (Zone 3) aorta, depends on injury patterns, but remains a highly debated topic. We sought to compare the proximal hemodynamic support provided by Zone 1 versus Zone 3 REBOA placement and the degree of hemodynamic instability upon reperfusion following intervention.

METHODS: Eighteen anesthetized swine underwent controlled hemorrhage of 25% total blood volume, followed by 45 minutes of Zone 1 REBOA, Zone 3 REBOA, or no intervention (control). They were then resuscitated with shed blood, aortic balloons were deflated, and 5 hours of critical care ensued prior to euthanasia. Physiologic parameters were recorded continuously, and blood was drawn for analysis at specified intervals. Significance was defined as p < 0.05.

RESULTS: There were no significant differences between groups at baseline or during the initial 30 minutes of hemorrhage. During the intervention period, average proximal MAP was significantly greater in Zone 1 animals when compared with Zone 3 animals (127.9 ± 1.3 vs. 53.4 ± 1.1 mm Hg) and greater in Zone 3 animals when compared with control animals (42.9 ± 0.9 mm Hg). Lactate concentrations were significantly higher in Zone 1 animals (9.6 ± 0.4 mmol/L) when compared with Zone 3 animals (5.1 ± 0.3 mmol/L) and control animals (4.2 ± 0.8 mmol/L).

CONCLUSIONS: In our swine model of hemorrhagic shock, Zone 3 REBOA provided minimal proximal hemodynamic support when compared with Zone 1 REBOA, albeit with less ischemic burden and instability upon reperfusion. In cases of impending hemodynamic collapse, Zone 1 REBOA placement may be more efficacious regardless of injury pattern, whereas Zone 3 should be reserved only for relatively stable patients with ongoing distal hemorrhage.