Massive Hemorrhage

#### MASSIVE HEMORRHAGE (GENERAL)

JAMA. 2018 Aug 14;320(6):589-590

# Stop the bleeding: Educating the public.

Fisher A, Bulger E, Gestring M

Uncontrolled hemorrhage is the single most preventable cause of death following traumatic injury. Bystanders can control bleeding and potentially save lives if they are willing to intervene. Bystander engagement has been identified as a vital first link in the chain of survival following injury.

Efforts to promote greater awareness about bleeding control techniques in the civilian environment evolved through lessons learned from the military. The conflicts in Iraq and Afghanistan have led to significant improvements in the identification and out-of-hospital treatment of massive hemorrhage.

Crit Care Med. 2018 Mar;46(3):447-453

# Transport Time and Preoperating Room Hemostatic Interventions Are Important: Improving Outcomes After Severe Truncal Injury.

Holcomb J

OBJECTIVES: Experience in the ongoing wars in Iraq and Afghanistan confirm that faster transport combined with effective prehospital interventions improves the outcomes of patients suffering hemorrhagic shock. Outcomes of patients with hemorrhagic shock and extremity bleeding have improved with widespread use of tourniquets and early balanced transfusion therapy. Conversely, civilian patients suffering truncal bleeding and shock have the same mortality (46%) over the last 20 years. To understand how to decrease this substantial mortality, one must first critically evaluate all phases of care from point of injury to definitive hemorrhage control in the operating room.

DATA SOURCES: Limited literature review.

DATA SYNTHESIS: The peak time to death after severe truncal injury is within 30 minutes of injury. However, when adding prehospital transport time, time spent in the emergency department, followed by the time in the operating room, it currently takes 2.1 hours to achieve definitive truncal hemorrhage control. This disparity in uncontrolled truncal bleeding and time to hemorrhage control needs to be reconciled. Prehospital and emergency department whole blood transfusion and temporary truncal hemorrhage control are now possible.

CONCLUSIONS: The importance of rapid transport, early truncal hemorrhage control and whole blood transfusion is now widely recognized. Prehospital temporary truncal hemorrhage control and whole blood transfusion should offer the best possibility of improving patient outcomes after severe truncal injury.

J Trauma Acute Care Surg. 2018 Jul;85(1S Suppl 2):S27-S32. Doi 10.1097/TA.0000000000001800.

# Assessment of prehospital hemorrhage and airway care using a simulation model.

Skube M, Witthuhn S, Mulier K, Boucher B, Lusczek E, Beilman G

BACKGROUND: The quality of prehospital care impacts patient outcomes. Military efforts have focused on training revision and the creation of high-fidelity simulation models to address potentially survivable injuries. We sought to investigate the applicability of models emphasizing hemorrhage control and airway management to a civilian population.

METHODS: Prehospital health care providers (PHPs) undergoing their annual training were enrolled. A trauma scenario was simulated with two modules: hemorrhage control and airway management. Experienced raters used a validated tool to assess performance. Pearson correlation, logistic regression, and χ tests were used for analysis.

RESULTS: Ninety-five PHPs participated with a mean experience of 15.9 ± 8.3 years, and 7.4% reported past military training. The PHPs' overall execution rate of the six hemorrhage control measures varied from 38.9% to 88.4%. The median blood loss was 1,700 mL (interquartile range, 1,043-2,000), and the mean global rater score was 25.0 ± 7.4 (scale, 5-40). There was a significant relationship between PHP profession and past military experience to their consideration of blood transfusion and tranexamic acid. An inverse relationship between blood loss and global rater score was found (r = -0.59, n = 88, p = 1.93 × 10). After simulated direct laryngoscope failure in the airway module, 58% of PHPs selected video laryngoscopy over placement of a supraglottic airway. Eighty-six percent of participants achieved bilateral chest rise in the manikin regardless of management method. Participants reported improved comfort with skills after simulation.

CONCLUSION: Our data reveal marginal performance in hemorrhage control regardless of the PHP's prior experience. The majority of PHPs were able to secure an advanced airway if direct laryngoscope was unavailable with a predisposition for video laryngoscopy over supraglottic airway. Our findings support the need for continued training for PHPs highlighting hemorrhage control maneuvers and increased familiarity with airway management options. Improved participant confidence posttraining gives credence to simulation training.

LEVEL OF EVIDENCE: Prognostic/epidemiological study, level III.

#### TOURNIQUETS / EXTREMITY BLEEDING

J Trauma Acute Care Surg. 2018 Sep;85(3):495-499

# Tourniquet use is not associated with limb loss following military lower extremity arterial trauma.

Kauvar D, Miller D, Walters T

BACKGROUND: The effect of battlefield extremity tourniquet (TK) use on limb salvage and long-term complications following vascular repair is unknown. This study explores the influence of TK use on limb outcomes in military lower extremity arterial injury.

METHODS: The study database includes cases of lower extremity vascular injury from 2004 to 2012 with data recorded until discharge from military service. We analyzed all limbs with at least one named arterial injury from the femoral to the tibial level. Tourniquet (TK) and no TK (NTK) groups were identified. Univariate analyses were performed with significance set at p ≤ 0.05.

RESULTS: A total of 455 cases were included, with 254 (56%) having a TK for a median of 60 minutes (8-270 minutes). Explosive injuries (53%) and gunshot wounds (26%) predominated. No difference between TK and NTK was present in presence of fracture, level of arterial injury, type of arterial repair, or concomitant venous injury. More nerve injuries were present in the TK group, and Abbreviated Injury Scale extremity and Mangled Extremity Severity Score tended toward greater injury severity. Amputation and mortality rates did not differ between groups, but the incidence of severe edema, wound infection, and foot drop was higher in the TK group. Vascular above-knee amputation, arterial repair complication, and severe edema were higher in the TK group also (p = 0.10). Tourniquet duration of 60 minutes or longer was not associated with increased amputations, but more rhabdomyolysis was present.

CONCLUSION: Field TK use is associated with wound infection and neurologic compromise but not limb loss. This may be due to a more severe injury profile among TK limbs. Increased TK times may predispose to systemic, but not limb, complications.

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

J Spec Oper Med. Summer 2018;18(2):36-41.

# New and established models of limb tourniquet compared in simulated first aid.

Kragh JF Jr, Newton NJ, Tan AR, Aden JK 3d, Dubick MA.

BACKGROUND: The performance of a new tourniquet model was compared with that of an established model in simulated first aid.

METHODS: Four users applied the Combat Application Tourniquet (C-A-T), an established model that served as the control tourniquet, and the new SAM Extremity Tourniquet (SXT) model, which was the study tourniquet.

RESULTS: The performance of the C-A-T was better than that of the SXT for seven measured parameters versus two, respectively; metrics were statistically tied 12 times. The degree of difference, when present, was often small. For pretime, a period of uncontrolled bleeding from the start to a time point when the tourniquet first contacts the manikin, the bleeding rate was uncontrolled at approximately 10.4mL/s, and for an overall average of 39 seconds of pretime,

406mL of blood loss was calculated. The mean time to determination of bleeding control (± standard deviation [SD]) was 66 seconds (SXT, 70 ± 30 seconds; C-A-T, 62 ± 18 seconds; p = .0075). The mean ease-of-use score was 4 (indicating easy) on a scale of 1 to 5, with 5 indicating very easy (mean ± SD: SXT, 4 ± 1; C-A-T, 5 ± 0; p < .0001). C-A-T also performed better for total trial time, manikin damage, blood loss rate, pressure, and composite score. SXT was better for pretime and unwrap time. All users intuitively self-selected the speed at which they applied the tourniquets and that speed was similar in all of the required steps. However, by time segments, one user went slowest in each segment while the other three generally went faster.

CONCLUSIONS: In simulated first aid with tourniquets, better results generally were seen with the C-A-T than with the SXT in terms of performance metrics. However, the degree of difference, when present, was often small.

J Am Coll Surg. 2018 Sep;227(3):332-345

# From pull to pressure: effects of tourniquet buckles and straps.

Valliere M, Wall P, Buising C

BACKGROUND: Limb tourniquet pressures > 100 mmHg before tightening system use eases achieving arterial occlusion, minimizes tightening system problems, and probably minimizes discomfort. This study examined effects of buckle and strap features on converting pulling force to strap pressure.

STUDY DESIGN: Twenty-two buckle and strap combinations were evaluated using a thigh-diameter, ballistic gel cylinder and 3 thighs. Weights of 14.11, 27.60, and 41.11 kg provided pulling force. The contribution of buckle movement was evaluated: all buckles on gel and 12 on thighs allowed limited vertical movement, 12 on gel and 4 on thighs held static.

RESULTS: Force conversion patterns per combination were similar on gel and thighs, including greatest force conversion with some buckle movement allowed. Smooth, round redirect buckles without engagement of a strap-securing mechanism had the best conversions of pulling force to tourniquet pressure; 2 achieved arterially occlusive pressures, neither commercially available. Among hook-and-loop secured tourniquets and threaded for self-securing tourniquets, the Generation 7 Combat Application Tourniquet (C-A-T7) and the Tactical Ratcheting Medical Tourniquet (Tac RMT) had the best conversions of pull to pressure (thigh applications/each weight, mean ± SD: C-A-T7 91 ± 11, 164 ± 30, 228 ± 34 mmHg; Tac RMT 82 ± 13, 150 ± 16, 222 ± 17 mmHg). Other Ratcheting Medical Tourniquets with the same buckle but different strap fabrics performed less well. Even lower pressures occurred with the Tactical Mechanical Tourniquet, the Special Operations Forces Tactical Tourniquet, the Parabelt, and the SAM XT Extremity Tourniquet (165 ± 11, 178 ± 13, 131 ± 14, and 106 ± 14 mmHg, all at 41.11 kg, respectively).

CONCLUSIONS: Buckle design and strap fabric affect the conversion of pulling force to tourniquet strap pressure. Low-friction, smooth, round redirects allow the best conversion.

#### HEMOSTATICS

Emerg Med J. 2018 Jul;35(7):449-457

# Prehospital haemostatic dressings for trauma: a systematic review.

Boulton A, Lewis C, Naumann D, Midwinter M

BACKGROUND: Haemorrhage is a major cause of mortality and morbidity following both military and civilian trauma. Haemostatic dressings may offer effective haemorrhage control as part of prehospital treatment.

AIM: To conduct a systematic review of the clinical literature to assess the prehospital use of haemostatic dressings in controlling traumatic haemorrhage, and determine whether any haemostatic dressings are clinically superior.

METHODS: MEDLINE and EMBASE databases were searched using predetermined criteria. The reference lists of all returned review articles were screened for eligible studies. Two authors independently undertook the search, performed data extraction, and risk of bias and Grading of Recommendations, Assessment, Development and Evaluation quality assessments. Meta-analysis could not be undertaken due to study and clinical heterogeneity.

RESULTS: Our search yielded 470 studies, of which 17 met eligibility criteria, and included 809 patients (469 military and 340 civilian). There were 15 observational studies, 1 case report and 1 randomised controlled trial. Indications for prehospital haemostatic dressing use, wound location, mechanism of injury, and source of bleeding were variable. Seven different haemostatic dressings were reported with QuikClot Combat Gauze being the most frequently applied (420 applications). Cessation of bleeding ranged from 67% to 100%, with a median of 90.5%. Adverse events were only reported with QuikClot granules, resulting in burns. No adverse events were reported with QuikClot Combat Gauze use in three studies. Seven of the 17 studies did not report safety data. All studies were at risk of bias and assessed of 'very low' to 'moderate' quality.

CONCLUSIONS: Haemostatic dressings offer effective prehospital treatment for traumatic haemorrhage. QuikClot Combat Gauze may be justified as the optimal agent due to the volume of clinical data and its safety profile, but there is a lack of high-quality clinical evidence, and randomised controlled trials are warranted.

LEVEL OF EVIDENCE: Systematic review, level IV.

#### JUNCTIONAL HEMORRHAGE

J Trauma Acute Care Surg. 2018 Jul 5 Epub ahead of print

# Abdominal Aortic and Junctional Tourniquet release after 240 min is survivable and associated with small intestine and liver ischemia after porcine class II hemorrhage.

Brännström A, Rocksén D, Hartman J, Nyman N, BSc J, Arborelius U, Günther M

BACKGROUND: Uncontrolled hemorrhage is a leading cause of tactical trauma related deaths. Hemorrhage from the pelvis and junctional regions are particularly difficult to control due to the inability of focal compression. The Abdominal Aortic and Junctional Tourniquet (AAJT) occludes aortic blood flow by compression of the abdomen. The survivability of tourniquet release beyond 120 min is unknown and fluid requirements to maintain sufficient blood pressure during prolonged application are undetermined. We therefore compared 60 min and 240 min applications and release of the AAJT for 30 min, with crystalloid fluid therapy, after a class II hemorrhage.

METHODS: 60 kg anesthetized pigs were subjected to [SWUNG DASH]900 ml hemorrhage and AAJT application for 60 min (n=5), 240 min (n=5), fluid therapy only for 240 min (n=5) and reperfusion for 30 min.

RESULTS: AAJT application was hemodynamically and respiratory tolerable for 60 min and 240 min. Cumulative fluid requirements decreased by 64%, comparable to 3000 ml of crystalloids. Mechanical ventilation was impaired. AAJT increased the core temperature by 0.9°C compared to fluid therapy. Reperfusion consequences were reversible after 60 min but not after 240 min. 240 min application resulted in small intestine and liver ischemia, persisting hyperkalemia, metabolic acidosis and myoglobinemia, suggesting rhabdomyolysis.

CONCLUSIONS: AAJT application for 240 min with reperfusion was survivable in an intensive care setting and associated with abdominal organ damage. Long time consequences and spinal cord effects was not assessed. We propose an application time limit within 60-240 min, though further studies are needed to increase the temporal resolution. The AAJT may be considered a rescue option to maintain central blood pressure and core temperature in cases of hemorrhagic shock from extremity bleedings, if fluid therapy is unavailable or the supply limited.Therapeutic study, level II.

J Spec Oper Med. Summer 2018;18(2):71-74.

# Junctional tourniquet use of during combat operations Afghanistan: the prehospital trauma registry experience.

Schauer SG, April MD, Fisher AD, Cunningham CW, Gurney J.

BACKGROUND: Hemorrhage is the leading cause of potentially preventable death on the battlefield. Although the resurgence of limb tourniquets revolutionized hemorrhage control in combat casualties in the recent conflicts, the mortality rate for patients with junctional hemorrhage is still high. Junctional tourniquets (JTQs) offer a mechanism to address the high mortality rate. The success of these devices in the combat setting is unclear given a dearth of existing data.

METHODS: From the Prehospital Trauma Registry (PHTR) and the Department of Defense Trauma Registry, we extracted cases of JTQ use in Afghanistan.

RESULTS: We identified 13 uses of a JTQ. We excluded one case in which an improvised pelvic binder was used. Of the remaining 12 cases of JTQ use, seven had documented success of hemorrhage control, three failed to control hemorrhage, and two were missing documentation regarding success or failure.

CONCLUSION: We report 12 cases of prehospital use of JTQ in Afghanistan. The findings from this case series suggest these devices may have some utility in achieving hemorrhage control strictly at junctional sites (e.g., inguinal creases). However, they also highlight device limitations. This analysis demonstrates the need for continued improvements in technologies for junctional hemorrhage control, prehospital documentation, data fidelity and collection, as well as training and sustainment of the training for utilization of prehospital hemorrhage control techniques.