Prehospital tourniquet use in Operation Iraqi Freedom: effect on hemorrhage control and outcomes

Therapeutic limb hypothermia for the treatment of traumatic acute limb ischemia

Acute limb ischaemia (ALI) is an emergent clinical condition that strains pre-hospital resources and impacts healthcare costs and patient quality of life. Hypothermia has long been used in clinical and research settings to mitigate ischaemic damage in tissues, but prompt reperfusion is needed to prevent loss of limb or function from ALI. To address the unmet need for pre-hospital intervention of threatened limbs awaiting definitive specialty care, we have focused on controlled application of hypothermia. Over years of animal experiments, phantom limb creation, and materials selection, we conceptualised and created a portable limb-cooling device that can be used alone or combined with a traditional tourniquet or resuscitative endovascular balloon occlusion of the aorta. Here, we describe our process of building and testing the device, from computer simulation through animal-limb metabolic studies, to prototype testing.

Exploring Combat Tourniquet Application Errors and Duration Among Skilled and Novice Medical Trainees

INTRODUCTION

The use of tourniquets in combat medicine continues to be a key focus as they have consistently been shown to combat one of the leading causes of preventable death on the battlefield, massive hemorrhage to extremities. The present study analyzed tourniquet application among combat medics (68W) and combat lifesavers (CLSs) in a training environment to determine whether trainees' performance is consistent among one another and whether performance can be associated with participant demographics such as experience or role.

MATERIALS AND METHODS

Study participants treated male and female patient simulators within a tactical field care phase, both of which experienced an amputated leg and required the application of a Combat Application Tourniquet (CAT). To assess tourniquet application variability and performance, a series of application subtasks and potential errors were measured via video coding of the scenarios by a team of 5 coders. Time to tourniquet application and tourniquet application duration were also coded to assess correlations between application duration and variability or performance.

RESULTS

Results from analyzing tourniquet application subtasks and errors through a series of one-way ANOVA tests showed that application of the CAT first, hasty CAT application, and high tourniquet application were not predictive of participant role, time within the role, and self-reported tourniquet skill, confidence, or experience. Such demographic variables were also not predictive of successful tourniquet application as defined by the number of windlass rod rotations. Results from binomial logistic regressions showed that participant role and self-reported tourniquet skill and experience were predictors of tourniquet application duration.

CONCLUSION

The findings suggest that high variability in CAT application methodology and performance exists among CLS and combat medics, which is largely not predictable by various demographics such as role, experience within the designated role, and self-reported confidence, skill, or experience. The observed disconnect between training or experience and CAT application performance suggests substantial variability in the consistency of training for both CLS and 68W soldiers. These inconsistencies may stem from variability in instructor knowledge, teaching styles, or training materials or may be developed through informal methods such as experiences in the field or recommendations from colleagues and experts. These findings highlight a potential need to reassess CAT application training, particularly in regard to consistency and validation. Finally, it should be noted that the study's findings may be limited or fail to capture some study effects because of the sample size and wide range of reported experience among participants.

The Perfect Med Bag is One that Doesn't Fall Off a Cliff: A Combat Mass Casualty Case

Military trauma provides a unique pattern of injuries due to the high velocity, high kinetic energy ammunition utilized, and the high prevalence of blast injury. To further complicate this, military trauma often occurs in austere environments with limited logistical support. Therefore, military medical providers are forced to learn nonstandard techniques and when necessary, practice a level of improvisation not commonly seen in other medical fields. The case presented in this manuscript is a prime example of these challenges. At the onset of fighting both the medic's rucksack, carrying with it the primary source of medical gear and the precious supply of cold-stored blood products are lost. The scenario was further complicated by rough mountainous terrain and a prolonged evacuation time. The medical provider was forced to utilize nonstandard devices such as an improvised junctional tourniquet which used a rock to focus the devices pressure. They also adapted their basic understanding of surgical procedures to conduct a vascular cutdown procedure for wound exposure and effectively pack an otherwise non-compressible wound to a major artery. Despite a significant loss of equipment, the medic and their team were able to successfully care for a number of patients in this mass casualty scenario.

Whole blood transfusion among allied partnerships: unified and interoperable blood banking for optimised care

Whole blood transfusion is being increasingly used for trauma resuscitation, particularly in military settings. Low-titre group O whole blood simplifies the logistical challenges and maximises the benefits of blood transfusion when compared with component therapy in austere battlefield conditions. Screening protocols and blood testing requirements for prescreened donors in walking blood banks (WBBs), which are used for emergency transfusions, are established by both the USA and most partner nations, though they are not necessarily uniform across these combined forces. Interoperability and standardisation of blood bank resources and protocols across allied forces in multinational military operations, including uniformity in screening processes, collection methods and storage is essential to the provision of safe and effective blood product transfusions in this austere setting. Predeployment screening, multinational training exercises and universal WBB sets with instructions in multiple languages can help enhance the interoperability of combined multinational operations and create a more efficient WBB system. Standardisation of blood collection, nomenclature, equipment and screening practices will allow for the most optimal utilisation of whole blood resources across a multinational battlefield.

Characteristics and Outcomes of Prehospital Tourniquet Use for Trauma in the United States

INTRODUCTION

The use of the extremity tourniquet in military environments has reduced preventable deaths due to exsanguinating hemorrhage, leading to increased use in civilian settings. However, the outcomes of contemporary prehospital tourniquet use in civilian settings are not well-described nationally. The objective of this study was to describe the characteristics and outcomes following prehospital tourniquet use by emergency medical services (EMS) in the United States.

METHODS

All trauma activations reported to the National EMS Information System 2019 (NEMSIS) were included. Patients who had ≥1 tourniquet applied were identified. Descriptive analyses were used to compare characteristics between tourniquet and no-tourniquet cohorts. Coarsened exact matching was performed to generate a k2k match (on age, sex, lowest-systolic blood pressure, initial patient acuity, provider's initial impression, injury mechanism, and presence of upper/lower extremity injuries) and used to compare outcomes. Trauma patients who may have potentially benefited from tourniquet application (extremity injury, shock index ≥1 and no documented tourniquet application) were identified.

RESULTS

A total of 7,161 tourniquets were applied among 4,571,379 trauma activations (1.6/1000 activations). Patients in the tourniquet cohort were younger (40 ± 18 vs 52 ± 26 mean ± SD years), more hypotensive (16.1% vs. 2.5%) and had higher initial acuity (65.0% critical/emergent vs. 20.6%) [p < 0.01 for all]. A total of 7,074 patients in the tourniquet cohort were matched with 7,074 patients in the non-tourniquet cohort. Post-match analysis revealed that the patients in tourniquet cohort had a higher final acuity (80.8% vs. 75.0%, p < 0.01), lower scene-time (15.4 ± 13.6 vs. 17.0 ± 14.2 mean ± SD minutes, p < 0.01), and higher survival-to-hospital (83.6% vs. 75.1%, p < 0.01). A total of 141,471 trauma patients who may have potentially benefited from tourniquet application were identified.

CONCLUSION

Prehospital tourniquet use by EMS in the United States is associated with lower scene-time and improved survivability to hospital. Results indicate that patients might benefit from wider tourniquet use in the civilian prehospital setting.

Prehospital extremity tourniquet placements-performance evaluation of non-EMS placement of a lifesaving device

BACKGROUND

The education of civilians and first responders in prehospital tourniquet (PT) utilization has spread rapidly. We aimed to describe trends in emergency medical services (EMS) and non-EMS PT utilization, and their ability to identify proper clinical indications and to appropriately apply tourniquets in the field.

METHODS

A retrospective cohort study was conducted to evaluate all adult patients with PTs who presented at two Level I trauma centers between January 2015 and December 2019. Data were collected via an electronic patient query tool and cross-referenced with institutional Trauma Registries. Medically trained abstractors determined if PTs were clinically indicated (limb amputation, vascular hard signs, injury requiring hemostasis procedure, or significant documented blood loss). PTs were further designated as appropriately or inappropriately applied (based on tourniquet location, venous tourniquet, greater than 2-h ischemic time). Descriptive statistics and univariate analyses were performed.

RESULTS

146 patients met inclusion criteria. The incidence of yearly PT placements increased between 2015 and 2019, with an increase in placement by non-EMS personnel (police, firefighter, bystander, and patient). Improvised PTs were frequently utilized by bystanders and patients, whereas first responders had high rates of commercial tourniquet use. A high proportion of tourniquets were placed without indication (72/146, 49%); however, the proportion of PTs placed without a proper indication across applier groups was not statistically different (p = 0.99). Rates of inappropriately applied PTs ranged from 21 to 46% across all groups applying PTs.

CONCLUSIONS

PT placement was increasingly performed by non-EMS personnel. Present data indicate that non-EMS persons applied PTs at a similar performance level of those applied by EMS. Study LevelLevel III.

Stop the Bleed: A Prospective Evaluation and Comparison of Tourniquet Application in Security Personnel Versus Civilian Population

INTRODUCTION

Stop the Bleed (STB) is a national training program aiming to decrease the mortality associated with life-threatening bleeding due to injury. The purpose of this study was to evaluate the efficacy and confidence level of security personnel placing a tourniquet (TQ) compared to civilians.

METHODS

Pre and post questionnaires were shared with security personnel (Group 1) and civilians (Group 2). Both groups were assessed to determine comfort level with TQ placement. Time and success rate for placement was recorded pre- and post-STB training. A generalized linear mixed model or generalized estimating equations was used to compare pre and post measurements.

RESULTS

There were 234 subjects enrolled. There was a statistically significant improvement between the pre- and post-training responses in both groups with respect to comfort level in placing a TQ. Participants also demonstrated increased familiarity with the anatomy and bleeding control after STB training. A higher successful TQ placement was obtained in both groups after STB training (Pre-training: Group 1 [17.4%], Group 2 [12.8%]; Post-training: Group 1 [94.8%], Group 2 [92.3%]). Both groups demonstrated improved time to TA placement with a longer mean time improvement achieved in Group 1. Although the time to TQ placement pre-and post-training was statistically significant, we found that the post-training times between Groups 1 and 2 were similar (P = .983).

CONCLUSIONS

Participants improved their confidence level with the use of hemorrhage control techniques and dramatically increased the rate and time to successful placement of a TQ. While civilians had the greatest increase in comfort level, the security personnel group saw the most significant reduction in the time to successful TQ placement. These findings highlight the critical role of STB in educating and empowering both civilians and security personnel in bleeding control techniques.

Prehospital Tourniquets Placed on Limbs Without Major Vascular Injuries, has the Pendulum Swung Too far?

BACKGROUND

Combat applications of tourniquets for extremity trauma have led to increased civilian prehospital tourniquet use. Studies have demonstrated that appropriate prehospital tourniquet application can decrease the incidence of arrival in shock without increasing limb complications. The aim of this study was to examine outcomes of prehospital tourniquet placement without definitive vascular injury.

METHODS

Retrospective review was performed of a prospectively maintained database by the American Association for the Surgery of Trauma from 29 trauma centers. Patients in this subset analysis did not have a significant vascular injury as determined by imaging or intra-operatively. Patients who received prehospital tourniquets (PHTQ) were compared to patients without prehospital tourniquets (No-PHTQ). Outcomes were amputation rates, nerve palsy, compartment syndrome, and in-hospital mortality.

RESULTS

A total of 622 patients had no major vascular injury. The incidence of patients without major vascular injury was higher in the PHTQ group (n = 585/962, 60.8 vs n = 37/88, 42.0%, P < .001). Cohorts were similar in age, gender, penetrating mechanism, injury severity scores (ISS), abbreviated injury score (AIS), and mortality (P > .05). Amputation rates were 8.3% (n = 49/585) in the PHTQ group compared to 0% (n = 0/37) in the No-PHTQ group. Amputation rates were higher in PHTQ than No-PHTQ with similar ISS and AIS (P = .96, P = .59). The incidence of nerve palsy and compartment syndrome was not different (P > .05).

CONCLUSIONS

This study showed a significant amount of prehospital tourniquets are being placed on patients without vascular injuries. Further studies are needed to elucidate the appropriateness of prehospital tourniquets, including targeted education of tourniquet placement.

Tourniquet Application for Bleeding Control in a Rural Trauma System: Outcomes and Implications for Prehospital Providers

Introduction: Uncontrolled bleeding is a preventable cause of death in rural trauma. Herein, we examined the appropriateness, effectiveness, and safety of tourniquet application for bleeding control in a rural trauma system.Methods: Medical records of adult patients admitted to our academic Level I trauma center between July 2015 and December 2018 were retrospectively reviewed. Demographics (age, gender), injury (Injury severity score, Glascow Coma scale, mechanism of injury), tourniquet (type, tourniquet application site, tourniquet duration, place of application and removal, indication), and outcome data (complications such as amputation, acute kidney injury, rhabdomyolysis, or nerve palsy and mortality) were collected. Tourniquet indications, effectiveness, and complications were evaluated. Data were compared to those in urban settings.Results: Ninety-two patients (94 tourniquets) were identified, of which 58.7% incurred penetrating injuries. Eighty-seven tourniquets (92.5%) were applied in the prehospital setting. Twenty tourniquets (21.3%) were applied to patients without an appropriate indication. Two of these tourniquets were applied in a hospital setting, while 18 occurred in the prehospital setting (p = 0.638). Patients with a non-indicated tourniquet presented with a higher hemoglobin level on admission, received less packed red blood cell units within the first 24 hours of hospitalization, and were less likely to require surgery for hemostasis. None of the non-indicated tourniquets led to a complication. Indicated tourniquets were deemed ineffective in seven cases (9.5%); they were all applied in the prehospital setting. The average tourniquet time was 123 min in rural vs. 48 min in urban settings, p < 0.001. There was no significant difference in mortality, amputation rates and incidence of nerve palsy between the rural and urban settings.Conclusion: Even with long transport times, early tourniquet application for hemorrhage control in rural settings is safe with no significant attributable morbidity and mortality compared to published studies on urban civilian tourniquet use. The observed rates of non-indicated and ineffective tourniquets indicate suboptimal tourniquet usage and application. Opportunity exists for standardized hemorrhage control training on the use of direct pressure and pressure dressings, indications for tourniquet use, and effective tourniquet application.

Administration of particulate oxygen generators improves skeletal muscle contractile function after ischemia-reperfusion injury in the rat hindlimb

Extended tourniquet application, often associated with battlefield extremity trauma, can lead to severe ischemia-reperfusion (I/R) injury in skeletal muscle. Particulate oxygen generators (POGs) can be directly injected into tissue to supply oxygen to attenuate the effects of I/R injury in muscle. The goal of this study was to investigate the efficacy of a sodium percarbonate (SPO)-based POG formulation in reducing ischemic damage in a rat hindlimb during tourniquet application. Male Lewis rats were anesthetized and underwent tourniquet application for 3 h at a pressure of 300 mmHg. Shortly after tourniquet inflation, animals received intramuscular injections of either 0.2 mg/mL SPO with catalase (n = 6) or 2.0 mg/mL SPO with catalase (n = 6) directly into the tibialis anterior (TA) muscle. An additional Tourniquet-Only group (n = 12) received no intervention. Functional recovery was monitored by in vivo contractile testing of the hindlimb at 1, 2, and 4 wk after injury. By the 4 wk time point, the Low-Dose POG group continued to show improved functional recovery (85% of baseline) compared with the Tourniquet-Only (48%) and High-Dose POG (56%) groups. In short, the low-dose POG formulation appeared, at least in part, to mitigate the impact of ischemic tissue injury, thus improving contractile function after tourniquet application. Functional improvement correlated with maintenance of larger muscle fiber cross-sectional area and the presence of fewer fibers containing centrally located nuclei. As such, POGs represent a potentially attractive therapeutic solution for addressing I/R injuries associated with extremity trauma.NEW & NOTEWORTHY Skeletal muscle contraction was evaluated in the same animals at multiple time points up to 4 wk after injury, following administration of particulate oxygen generators (POGs) in a clinically relevant rat hindlimb model of tourniquet-induced ischemia. The observed POG-mediated improvement of muscle function over time confirms and extends previous studies to further document the potential clinical applications of POGs. Of particular significance in austere environments, this technology can be applied in the absence of an intact circulation.

Evaluating the Tactical Combat Casualty Care principles in civilian and military settings: systematic review, knowledge gap analysis and recommendations for future research

OBJECTIVES

The Tactical Combat Casualty Care (TCCC) guidelines detail resuscitation practices in prehospital and austere environments. We sought to review the content and quality of the current TCCC and civilian prehospital literature and characterize knowledge gaps to offer recommendations for future research.

METHODS

MEDLINE, EMBASE, CINAHL, and Cochrane Central Register of Controlled Trials were searched for studies assessing intervention techniques and devices used in civilian and military prehospital settings that could be applied to TCCC guidelines. Screening and data extraction were performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Quality appraisal was conducted using appropriate tools.

RESULTS

Ninety-two percent (n=57) of studies were observational. Most randomized trials had low risk of bias, whereas observational studies had higher risk of bias. Interventions of massive hemorrhage control (n=17) were wound dressings and tourniquets, suggesting effective hemodynamic control. Airway management interventions (n=7) had high success rates with improved outcomes. Interventions of respiratory management (n=12) reported low success with needle decompression. Studies assessing circulation (n=18) had higher quality of evidence and suggested improved outcomes with component hemostatic therapy. Hypothermia prevention interventions (n=2) were generally effective. Other studies identified assessed the use of extended focused assessment with sonography in trauma (n=3) and mixed interventions (n=2).

CONCLUSIONS

The evidence was largely non-randomized with heterogeneous populations, interventions, and outcomes, precluding robust conclusions in most subjects addressed in the review. Knowledge gaps identified included the use of blood products and concentrate of clotting factors in the prehospital setting.

LEVEL OF EVIDENCE

Systematic review, level III.

Successful limb salvage beyond the golden time following blunt traumatic open complete transection of the femoral artery and vein in a patient with cardiac arrest: a case report

Background

Open complete transection of the femoral artery and vein following blunt trauma is extremely rare. Furthermore, even if the patient has been successfully resuscitated, it is sometimes difficult in most patients to preserve the injured limb, especially after damage control resuscitation. We report a case of open complete transection of the femoral artery and vein secondary to high-energy blunt trauma and a successful limb preservation treatment strategy.

Case presentation

A 57-year-old Asian man was transferred to hospital after having fallen from the 15th floor of a condominium. The patient was in cardiac arrest at the scene, but was successfully resuscitated by emergency medical services staff. On arrival, the patient’s hemodynamics were completely collapsed with active external bleeding from the thigh, so we immediately started resuscitation including activation of massive transfusion protocol and temporarily ligated the transected proximal superficial femoral artery, deep femoral artery just distal after branching lateral femoral circumflex artery and the superficial femoral vein. Following radiological findings showing a potential pelvic fracture with active bleeding, we also performed retroperitoneal packing in the resuscitation room and moved the patient to the angiography room for transcatheter arterial embolization. The patient’s consciousness was preserved and perfusion of the injured limb was barely maintained after his hemodynamics were adequately stabilized. As we detected weak perfusion of the lower limb via a potential collateral flow from the lateral femoral circumflex artery branches from deep femoral artery by pulse doppler of the dorsal pedis artery, we decided to reconstruct superficial femoral artery and vein at 24 h after injury using great saphenous vein bypass grafts. The patient was transferred to a rehabilitation hospital with good neurological and limb outcome after hospitalization for 52 days.

Conclusion

We successfully preserved the patient’s lower limb after cardiac arrest and complete transection of the femoral artery and vein and achieved a good neurological outcome. Even if a femoral artery needs to be ligated temporarily, careful observation and assessment should be performed so as not to lose the chance to salvage the limb even during damage control resuscitation.

An Eastern Association for the Surgery of Trauma multicenter trial examining prehospital procedures in penetrating trauma patients

BACKGROUND

Prehospital procedures (PHP) by emergency medical services (EMS) are performed regularly in penetrating trauma patients despite previous studies demonstrating no benefit. We sought to examine the influence of PHPs on outcomes in penetrating trauma patients in urban locations where transport to trauma center is not prolonged. We hypothesized that patients without PHPs would have better outcomes than those undergoing PHP.

METHODS

This was an Eastern Association for the Surgery of Trauma-sponsored, multicenter, prospective, observational trial of adults (18+ years) with penetrating trauma to the torso and/or proximal extremity presenting at 25 urban trauma centers. The impact of PHPs and transport mechanism on in-hospital mortality were examined.

RESULTS

Of 2,284 patients included, 1,386 (60.7%) underwent PHP. The patients were primarily Black (n = 1,527, 66.9%) males (n = 1,986, 87.5%) injured by gunshot wound (n = 1,510, 66.0%) with 34.1% (n = 726) having New Injury Severity Score of ≥16. A total of 1,427 patients (62.5%) were transported by Advanced Life Support EMS, 17.2% (n = 392) by private vehicle, 13.7% (n = 312) by police, and 6.7% (n = 153) by Basic Life Support EMS. Of the PHP patients, 69.1% received PHP on scene, 59.9% received PHP in route, and 29.0% received PHP both on scene and in route. Initial scene vitals differed between groups, but initial emergency department vitals did not. Receipt of ≥1 PHP increased mortality odds (odds ratio [OR], 1.36; 95% confidence interval [CI], 1.01-1.83; p = 0.04). Logistic regression showed increased mortality with each PHP, whether on scene or during transport. Subset analysis of specific PHP revealed that intubation (OR, 10.76; 95% CI, 4.02-28.78; p < 0.001), C-spine immobilization (OR, 5.80; 95% CI, 1.85-18.26; p < 0.01), and pleural decompression (OR, 3.70; 95% CI, 1.33-10.28; p = 0.01) had the highest odds of mortality after adjusting for multiple variables.

CONCLUSION

Prehospital procedures in penetrating trauma patients impart no survival advantage and may be harmful in urban settings, even when performed during transport. Therefore, PHP should be forgone in lieu of immediate transport to improve patient outcomes.

LEVEL OF EVIDENCE

Prognostic, level III.

Penetrating injuries in Germany - epidemiology, management and outcome an analysis based on the TraumaRegister DGU®

Background

The management of penetrating wounds is a rare challenge for trauma surgeons in Germany and Central Europe as a result of the low incidence of this type of trauma. In Germany, penetrating injuries are reported to occur in 4–5 % of the severely injured patients who are enrolled in the TraumaRegister DGU® (trauma registry of the German Trauma Society). They include gunshot injuries, knife stab injuries, which are far more common, and penetrating injuries of other origin, for example trauma caused by accidents. The objective of this study was to assess the epidemiology and outcome of penetrating injuries in Germany, with a particular focus on the level of care provided by the treating trauma centre to gain more understanding of this trauma mechanism and to anticipate the necessary steps in the initial treatment.

Materials and methods

Since 2009, the TraumaRegister DGU® has been used to assess not only whether a trauma was penetrating but also whether it was caused by gunshot or stabbing. Data were taken from the standard documentation forms that participating German hospitals completed between 2009 and 2018. Excluded were patients with a maximum abbreviated injury scale (MAIS) score of 1 with a view to obtaining a realistic idea of this injury entity, which is rare in Germany.

Results

From 2009 to 2018, there were 1123 patients with gunshot wounds, corresponding to a prevalence rate of 0.5 %, and 4333 patients with stab wounds (1.8 %), which were frequently caused by violent crime. The high proportion of intentionally self-inflicted gunshot wounds to the head resulted in a cumulative mortality rate of 41 % for gunshot injuries. Stab wounds were associated with a lower mortality rate (6.8 %). Every fourth to fifth patient with a gunshot or stab wound presented with haemorrhagic shock, which is a problem that is seen during both the prehospital and the inhospital phase of patient management. Of the patients with penetrating injuries, 18.3 % required transfusions. This percentage was more than two times higher than that of the basic group of patients of the TraumaRegister DGU®, which consists of patients with a MAIS ≥ 3 and patients with a MAIS of 2 who died or were treated on the intensive care unit.

Conclusions

In Germany, gunshot and stab wounds have a low incidence and are mostly caused by violent crime or attempted suicides. Depending on the site of injury, they have a high mortality and are often associated with major haemorrhage. As a result of the low incidence of these types of trauma, further data and analyses are required in order to provide the basis for evaluating the long-term quality of the management of patients with stab or gunshot wounds.

Tourniquets as a haemorrhage control measure in military and civilian care settings: An integrative review

AIMS AND OBJECTIVES

The aim of review was to describe and synthesise the evidence on the use of tourniquets to control haemorrhages, summarising both civilian and military use.

BACKGROUND

Trauma-related haemorrhage constitutes one of the most preventable deaths among injured patients, particularly in multi-casualty incidents and disasters. In this context, safe instruments such as tourniquets are essential to help healthcare professionals to minimise loss of life and maximise patient recovery.

DESIGN AND METHODS

An integrative review was conducted in Medline, Nursing & Allied Health Premium, and Health & Medical Collection, using published data until March 2021 and following the PRISMA guidelines.

RESULTS

A total of 25 articles were included. Evidence has been synthesised to understand the use of different types of tourniquets, environment of application, indication for their placement and potential complications associated with tourniquet placement.

CONCLUSIONS

Commercial tourniquets such as Combat Application Tourniquet or Emergency Tourniquet models are a valuable and safe instrument for haemorrhage control in both military and civilian out-of-hospital care settings. Nurses, as part of emergency teams, and other professionals should be aware that there is a possibility of adverse complications, but they are directly proportional to the time of tourniquet placement and generally temporary. In addition, national and international guidelines ensure the need for all civilian emergency services to be equipped with these devices, as well as for the training of healthcare professionals and first responders in their use.

RELEVANCE TO CLINICAL PRACTICE

Despite the lack of complications in the use of tourniquets in these cases, their use has been a matter of debate for decades. In this sense, this review yields up-to-date guidelines in the use of tourniquets, their recommendations and their significance among professionals to manage complicated situations.

Thermoreversible Reverse-Phase-Shift Foam for Treatment of Noncompressible Torso Hemorrhage

BACKGROUND

Noncompressible torso hemorrhage (NCTH) is a leading cause of traumatic exsanguination, requiring emergent damage control surgery performed by a highly trained surgeon in a sterile operating environment. A self-expanding, intraabdominally deployed, thermoreversible foam is one proposed method to potentially task shift temporizing hemostasis to earlier providers and additional settings. The purpose of this study was to assess the feasibility of using Fast Onset Abdominal Management (FOAM) in a lethal swine model of NCTH.

METHODS

This was a proof-of-concept study comparing FOAM intervention in large Yorkshire swine to historical control animals in the established Ross-Burns model of NCTH. After animal preparation, a Grade IV liver laceration was surgically induced, followed by a free bleed period of 10 min. FOAM was then deployed to a goal intraabdominal pressure of 60 mm Hg for 5 min, followed by a total 60-min observation period following injury.

RESULTS

At the end of the experiment, the FOAM agent was found to be distributed throughout the peritoneal cavity in all animals, without signs of iatrogenic injury. The FOAM group demonstrated a significantly higher mean arterial pressure compared with historical controls and a trend toward improved survival: 82% (9/11) compared with 50% for controls (7/14; P = 0.082).

CONCLUSIONS

This is the first study to describe the use of a thermoresponsive foam to manage NCTH and successfully demonstrated proof-of-concept feasibility of FOAM deployment. These results provide strong support for future, higher-powered studies to confirm improved survival with this novel intervention.

Prehospital Tourniquets in Civilians: A Systematic Review

OBJECTIVES

Terrorist attacks and civilian mass-casualty events are frequent, and some countries have implemented tourniquet use for uncontrollable extremity bleeding in civilian settings. The aim of this study was to summarize current knowledge on the use of prehospital tourniquets to assess whether their use increases the survival rate in civilian patients with life-threatening hemorrhages from the extremities.

DESIGN

Systematic literature review in Medline (Ovid), Embase (Ovid), Cochrane Library, and Epistemonikos was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Guidelines. The search was performed in January 2019.

SETTING

All types of studies that examined use of tourniquets in a prehospital setting published after January 1, 2000 were included.

PRIMARY/SECONDARY OUTCOMES

The primary outcome was mortality with and without tourniquet, while adverse effects of tourniquet use were secondary outcomes.

RESULTS

Among 3,460 screened records, 55 studies were identified as relevant. The studies were highly heterogeneous with low quality of evidence. Most studies reported increased survival in the tourniquet group, but few had relevant comparators, and the survival benefit was difficult to estimate. Most studies reported a reduced need for blood transfusion, with few and mainly transient adverse effects from tourniquet use.

CONCLUSION

Despite relatively low evidence, the studies consistently suggested that the use of commercial tourniquets in a civilian setting to control life-threatening extremity hemorrhage seemed to be associated with improved survival, reduced need for blood transfusion, and few and transient adverse effects.

2020 International Consensus on First Aid Science With Treatment Recommendations

This is the summary publication of the International Liaison Committee on Resuscitation's 2020 International Consensus on First Aid Science With Treatment Recommendations. It addresses the most recent published evidence reviewed by the First Aid Task Force science experts. This summary addresses the topics of first aid methods of glucose administration for hypoglycemia; techniques for cooling of exertional hyperthermia and heatstroke; recognition of acute stroke; the use of supplementary oxygen in acute stroke; early or first aid use of aspirin for chest pain; control of life- threatening bleeding through the use of tourniquets, haemostatic dressings, direct pressure, or pressure devices; the use of a compression wrap for closed extremity joint injuries; and temporary storage of an avulsed tooth. Additional summaries of scoping reviews are presented for the use of a recovery position, recognition of a concussion, and 6 other first aid topics. The First Aid Task Force has assessed, discussed, and debated the certainty of evidence on the basis of Grading of Recommendations, Assessment, Development, and Evaluation criteria and present their consensus treatment recommendations with evidence-to-decision highlights and identified priority knowledge gaps for future research. The 2020 International Consensus on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care (ECC) Science With Treatment Recommendations (CoSTR) is the fourth in a series of annual summary publications from the International Liaison Committee on Resuscitation (ILCOR). This 2020 CoSTR for first aid includes new topics addressed by systematic reviews performed within the past 12 months. It also includes updates of the first aid treatment recommendations published from 2010 through 2019 that are based on additional evidence evaluations and updates. As a result, this 2020 CoSTR for first aid represents the most comprehensive update since 2010.

2020 International Consensus on First Aid Science With Treatment Recommendations

This is the summary publication of the International Liaison Committee on Resuscitation's 2020 International Consensus on First Aid Science With Treatment Recommendations. It addresses the most recent published evidence reviewed by the First Aid Task Force science experts. This summary addresses the topics of first aid methods of glucose administration for hypoglycemia; techniques for cooling of exertional hyperthermia and heatstroke; recognition of acute stroke; the use of supplementary oxygen in acute stroke; early or first aid use of aspirin for chest pain; control of life-threatening bleeding through the use of tourniquets, hemostatic dressings, direct pressure, or pressure devices; the use of a compression wrap for closed extremity joint injuries; and temporary storage of an avulsed tooth. Additional summaries of scoping reviews are presented for the use of a recovery position, recognition of a concussion, and 6 other first aid topics. The First Aid Task Force has assessed, discussed, and debated the certainty of evidence on the basis of Grading of Recommendations, Assessment, Development, and Evaluation criteria and present their consensus treatment recommendations with evidence-to-decision highlights and identified priority knowledge gaps for future research.

Characterization of shape memory polymer foam hemostats in in vitro hemorrhagic wound models

Shape memory polymer foam hemostats are a promising option for future hemorrhage control in battlefield wounds. To enable their use as hemostatic devices, they must be optimized in terms of formulation and architecture, and their safety and efficacy must be characterized in animal models. Relevant in vitro models can be used for device optimization to help mitigate the excess use of animals and reduce costs of clinical translation. In this work, a simplified gunshot wound model and a grade V liver injury model were constructed. The models were used to characterize the effects of shape memory polymer foam hemostat geometry on wall pressures, application/removal times, hemorrhage (fluid loss), and fluid absorption in comparison with clinical controls. It was found that there is no benefit in over-sizing the hemostatic device relative to wound volume and that geometry effects are dependent upon the wound type. These models provide a rapid means for elucidation of promising hemostat geometries and formulations for use in future in vivo testing.

Impact of Succinct Training on Open Cricothyrotomy Performance: A Randomized, Prospective, Observational Study of U.S. Army First Responders

INTRODUCTION

Primary airway failure has become the second most common cause of potentially survivable battlefield fatality. Cricothyrotomy is taught to all U.S. military providers as a means of securing an airway in extremis. However, retrospective studies show that cricothyrotomy failure rates for U.S. military first responders performing the procedure in combat is 33%. Our hypothesis was that these rates could be improved.

MATERIALS AND METHODS

We conducted a randomized, prospective, observational study to evaluate the effects of inexpensive, succinct training on open cricothyrotomy performance by studying two unique U.S. Army First Responder participant groups. One participant group consisted of regular U.S. Army Medics (68 Ws). The second group was Special Operations Combat Medics. We evaluated both groups' baseline ability to correctly perform a cricothyrotomy and then randomly assigned individuals within each group to either a training or practice group.

RESULTS

The training group had a higher proportion of success and performed the cricothyrotomy faster than the practice group with 68 Ws group appearing to benefit most from training: their procedural success rates increased by an average of 23%, and their average time-to-correct-placement decreased by 21 seconds-a 33% improvement over baseline.

CONCLUSION

With one manikin, a qualified trainer, and $35 worth of expendable supplies, 10 medics could be trained in the procedure in just 2-3 hours. Our study suggests that this simple intervention has the potential to significantly improve U.S. Army First Responders' ability to correctly perform an open cricothyrotomy and drastically decrease the time needed to perform this lifesaving procedure correctly, possibly saving one in four potentially survivable combat casualties suffering from airway compromise.

Predictors and timing of amputations in military lower extremity trauma with arterial injury

INTRODUCTION

Military lower extremity arterial injuries present threats to life and limb. These injuries are common and limb salvage is a trauma system priority. Understanding the timing and predictors of amputation through the phases of casualty evacuation can help inform future limb salvage efforts. This study characterizes limbs undergoing amputation at different operationally relevant time points.

METHODS

A retrospective cohort study of casualties with lower extremity arterial injuries undergoing initial vascular limb salvage in Iraq and Afghanistan was undertaken. Amputations were grouped as having been performed early (in theater at Role 2 or 3) or late (after evacuation to Role 4 or 5). Further distinction was made between late and delayed (after discharge from initial hospitalization) amputations.

RESULTS

Four hundred fifty-five casualties met inclusion criteria with 103 amputations (23%). Twenty-one (20%) were performed in theater and 82 (80%) were performed following overseas evacuation. Twenty-one (26% of late amputations) were delayed, a median of 359 days from injury (interquartile range, 176-582). Most amputations were performed in the first 4 days following injury. Amputation incidence was highest in popliteal injuries (28%). Overall, amputation was predicted by higher incidence of blast mechanism and fracture and greater limb and casualty injury severity. Early amputations had higher limb injury severity than late amputations. Delayed amputations had greater incidence of motor and sensory loss and contracture than early amputations.

CONCLUSION

Casualty and limb injury severity predict predictors and timing of amputation in military lower extremity arterial injury. Amputation following overseas evacuation was more common than in-theater amputation, and functional loss is associated with delayed amputation. Future limb salvage efforts should focus on postevacuation and rehabilitative care.

LEVEL OF EVIDENCE

Epidemiologic study, level III.

A Comparison of Improvised and Commercially Available Point-of-Wounding Tourniquets in Simulated Traumatic Amputation with Catastrophic Hemorrhage

Introduction

Catastrophic hemorrhage is the leading cause of preventable trauma deaths in the military and civilian populations. The use of tourniquets by first responders (medical and nonmedically trained) is supported and has the potential to save lives if applied correctly.

Aims

We sought to examine the use of 5 tourniquets: 1 improvised and 4 commercially available tourniquets to investigate the time taken to stop simulated bleeding and to secure the device; evidence of rebleeding when the “blood pressure” was restored and to gain qualitative feedback on their application.

Materials and Methods

Four commercially available tourniquets (Combat Application Tourniquet [C-A-T], Special Operations Forces Tactical Tourniquet - Wide (SOFTT-W), stretch, wrap, and tuck tourniquet [SWAT-T], and the Tourni-key) and an improvised tourniquet (tie & wooden spoon) were tested on a complex silicone simulation model used to replicate catastrophic hemorrhage from a blast injury with above traumatic knee amputation (SAM 4.1 Trauma Simulation Ltd, UK). To limit the user variability, the same investigator applied each tourniquet and each was tested 3 times. No ethical approval was required to conduct this study.

Results

None of the devices took longer than 1 minute to secure. The C-A-T and SOFTT-W were quickest to occlude and secure. Although the Tourni-key took longer statistically, this was unlikely to be a clinically important difference. Compared to the others, the SOFTT-W rebled on 2 out of 3 applications. The improvised tourniquet had an obvious ligature effect because of its narrowness, followed by the Tourni-key. This effect was least evident with the SWAT-T; however, particular care was needed to ensure it was safely secured as it was slippery when wet.

Conclusions

All tourniquets tested were effective and swift to apply. The Tourni-key’s antipinch card seems helpful in reducing local pain under the windlass. Reinspection for rebleeding is important and should be routinely performed irrespective of the device. The width of the SWAT-T may be beneficial, thereby, reducing the risk of crush injury.

The Efficacy of Novel Commercial Tourniquet Designs for Extremity Hemorrhage Control: Implications for Spontaneous Responder Every Day Carry

Introduction:

Tourniquets (TQs) save lives. Although military-approved TQs appear more effective than improvised TQs in controlling exsanguinating extremity hemorrhage, their bulk may preclude every day carry (EDC) by civilian lay-providers, limiting availability during emergencies.

Study Objective:

The purpose of the current study was to compare the efficacy of three novel commercial TQ designs to a military-approved TQ.

Methods:

Nine Emergency Medicine residents evaluated four different TQ designs: Gen 7 Combat Application Tourniquet (CAT7; control), Stretch Wrap and Tuck Tourniquet (SWAT-T), Gen 2 Rapid Application Tourniquet System (RATS), and Tourni-Key (TK). Popliteal artery flow cessation was determined using a ZONARE ZS3 ultrasound. Steady state maximal generated force was measured for 30 seconds with a thin-film force sensor.

Results:

Success rates for distal arterial flow cessation were 89% CAT7; 67% SWAT-T; 89% RATS; and 78% TK (H 0.89; P = .83). Mean (SD) application times were 10.4 (SD = 1.7) seconds CAT7; 23.1 (SD = 9.0) seconds SWAT-T; 11.1 (SD = 3.8) seconds RATS; and 20.0 (SD = 7.1) seconds TK (F 9.71; P <.001). Steady state maximal forces were 29.9 (SD = 1.2) N CAT7; 23.4 (SD = 0.8) N SWAT-T; 33.0 (SD = 1.3) N RATS; and 41.9 (SD = 1.3) N TK.

Conclusion:

All novel TQ systems were non-inferior to the military-approved CAT7. Mean application times were less than 30 seconds for all four designs. The size of these novel TQs may make them more conducive to lay-provider EDC, thereby increasing community resiliency and improving the response to high-threat events.

Practicing Military Medicine in Truly Austere Environments: What to Expect, How to Prepare, When to Improvise

Introduction

The majority of the published literature on contemporary military medicine contradicts the concept of austere. Operational medicine is part of every armed conflict around the world, while armed forces of most countries internationally have limited medical resources especially in the front line. The aim of this review is to identify the particularities of a truly austere environment and present a short guide of preparation and action for military medical personnel internationally.

Materials and Methods

An exhaustive search of the existing English literature on operational and military medicine in austere environments was carried out in EMBASE and PubMed databases.

Results

This review included seminal and contemporary papers on the subject and synthesized a multiperspective short guide for operational medical personnel.

Discussion

Experience from forward surgical teams of the U.S. Army and humanitarian teams of physicians in war zones who work under precarious and austere circumstances has shown that the management of casualties requires different strategies than in higher levels of combat casualty care and in a civilian setting. A number of factors that must be controlled can be categorized into human, environmental, equipment-related, and socioeconomic. Surgeons and other medical personnel should have knowledge of these aspects beforehand and be adequately trained in peacetime. Physicians must master a number of essential skills and drugs, and be familiar with dosage regimens and side effects.

Conclusion

The military surgeon must be specially trained and prepared to use a wide range of skills in truly austere environments in contemporary conflicts.

Low-cost synthetic tourniquet training model

OBJECTIVE

to present a low-cost model for bleeding control training with the use of a tourniquet and the results of the training evaluation.

METHOD

low-cost and easy-to-purchase materials, such as upholstery foam, ethylene-vinyl acetate (EVA) sheet, plastic propulsion pump, saline container, water, school paint, serum equipment, rubber tubing for tourniquet, and a leg and an arm of a ghost mannequin, were used. In the model assembly, we created an active bleeding simulation system, which could only be controlled with the correct application of the tourniquet. The model was submitted to professional and academic evaluation.

RESULTS

the model was similar to human anatomy, proved to be practical in the bleeding control training with the use of a tourniquet, and had low cost.

CONCLUSION

the model for bleeding control training had excellent acceptability, was considered viable for educational purposes of tourniquet use, and had low cost.

Developing “Herd Immunity” in a Civilian Community Through Incorporation of “Just-In-Time” Tourniquet Application Training

Introduction:

Herd immunity, a concept normally applied in vaccinated populations, is a preventative measure to determine if a significant portion of a population can protect vulnerable individuals against a certain disease. Like vaccines, tourniquet education can be a form of herd immunity to protect vulnerable individuals in a population and prevent the loss of life from a peripheral hemorrhage. The authors have identified a deficiency in simple, quick, and effective hemorrhage control education. Therefore, to maximize herd immunity, the novel educational platform evaluates the efficacy of “Just-in-Time” (JiT) tourniquet application training.

Hypothesis/Problem:

The authors hypothesize that the utilization of JiT training will be effective in promoting both competence and confidence for individuals to utilize tourniquets in response to a disaster environment.

Methods:

This Institutional Review Board-approved study recruited medical students who were trained in hemorrhage control measures at a Level 1 Trauma Center. Tourniquet training sessions were held, and naïve civilians received tourniquet education. The subjects received a five- to ten-minute lesson on indications, contraindications, and application techniques of commercial and improvisational tourniquets. Participants subsequently applied a tourniquet to an instructor’s arm to demonstrate proper tourniquet application for a brachial artery hemorrhage. Pre- and post-educational surveys were completed to test participant competency and confidence.

Results:

Of the 104 subjects who completed the course, 97 had no prior training in hemorrhage control techniques, including commercial and improvisational tourniquet application. The mean pre-test score was 2.27/5.00 and the mean post-test score was 4.38/5.00, P &lt;.001 (n = 97). When queried “How competent would you feel applying a tourniquet (commercial or improvisational) on an individual with a bleeding wound?” 92/97 felt confident (95%), one felt less confident, and four felt no difference in confidence levels (P &lt;.001).

Conclusion:

Just-in-Time training is an effective method in teaching naïve civilians proper tourniquet application. This platform could serve as an alternative to more extensive training programs and requires less time, costs, and resources. If a significant number of individuals in a local community can effectively apply a tourniquet in a disaster scenario, a “herd immunity” effect could be achieved to control peripheral hemorrhages.

Triage Performance of School Personnel Using the SALT System

INTRODUCTION

The aim of this study was to determine if school personnel can understand and apply the Sort, Assess, Life-saving interventions, Treat/Transport (SALT) triage methods after a brief training. The investigators predicted that subjects can learn to triage with accuracy similar to that of medically trained personnel, and that subjects can pass an objective-structured clinical exam (OSCE) evaluating hemorrhage control.

METHODS

School personnel were eligible to participate in this prospective observational study. Investigators recorded subject demographic information and prior medical experience. Participants received a 30-minute lecture on SALT triage and a brief lecture and demonstration of hemorrhage control and tourniquet application. A test with brief descriptions of mass-casualty victims was administered immediately after training. Participants independently categorized the victims as dead, expectant, immediate, delayed, or minimal. They also completed an OSCE to evaluate hemorrhage control and tourniquet application using a mannequin arm.

RESULTS

Subjects from two schools completed the study. Fifty-nine were from a private school that enrolls early childhood through grade eight, and 45 from a public school that enrolls grades seven and eight (n = 104). The average subject age was 45 years and 68% were female. Approximately 81% were teachers and 87% had prior cardiopulmonary resuscitation (CPR) training. Overall triage accuracy was 79.2% (SD = 10.7%). Ninety-six (92.3%) of the subjects passed the hemorrhage control OSCE.

CONCLUSIONS

After two brief lectures and a short demonstration, school personnel were able to triage descriptions of mass-casualty victims with an overall accuracy similar to medically trained personnel, and most were able to apply a tourniquet correctly. Opportunities for future study include integrating high-fidelity simulation and mock disasters, evaluating for knowledge retention, and exploring the study population's baseline knowledge of medical care, among others.

Prehospital Interventions Performed in Afghanistan Between November 2009 and March 2014

OBJECTIVE

Care provided to a casualty in the prehospital combat setting can influence subsequent medical interactions and impact patient outcomes; therefore, we aimed to describe the incidence of specific prehospital interventions (lifesaving interventions (LSIs)) performed during the resuscitation and transport of combat casualties.

METHODS

We performed a prospective observational, IRB approved study between November 2009 and March 2014. Casualties were enrolled as they were cared for at nine U.S. military medical facilities in Afghanistan. Data were collected using a standardized collection form. Determination if a prehospital intervention was performed correctly, performed incorrectly, or was necessary but was not performed (missed LSIs) was made by the receiving facility's medical provider.

RESULTS

Two thousand one hundred and six patients met inclusion criteria. The mean age was 25 years and 98% were male. The most common mechanism of injury was explosion 57%. There were 236 airway interventions attempted, 183 chest procedures, 1,673 hemorrhage control, 1,698 vascular access, and 1,066 hypothermia preventions implemented. There were 142 incorrectly performed interventions and 360 were missed.

CONCLUSIONS

In our study, the most commonly performed prehospital LSI in a combat setting were for vascular access and hemorrhage control. The most common incorrectly performed and missed interventions were airway interventions and chest procedures respectively.

Teaching how to stop the bleed: does it work? A prospective evaluation of tourniquet application in law enforcement officers and private security personnel

INTRODUCTION

Stop the Bleed (STB) program was launched by the White House, for the use of bleeding control techniques at the scene of traumatic injury. The purpose of this study was to conduct an STB course in private security and law enforcement personnel.

METHODS

Pre- and post-questionnaire using the Likert scale was shared with participants on their knowledge and comfort level with the use of tourniquets. Participants were also observed while placing tourniquets and the time for placement recorded. The didactic portion and practical session of the STB was then taught and participants were again observed placing tourniquets and a questionnaire distributed. Fisher's exact tests or Wilcoxon matched-pairs signed-ranks tests were used to compare pre-post measurements.

RESULTS

A total of 151 subjects were enrolled over the course of seven sessions. The tourniquet was applied correctly by 17.2% (26/151) and 92.7% (140/151) at the pre- and post-instruction assessments, respectively (p < 0.001). Mean times to apply the tourniquet were 29.8 ± 18.5 and 18.7 ± 6.7 s, respectively (p < 0.001). Subjects reported their level of comfort with the tourniquet to be 5.1 ± 3.3 and 8.8 ± 2.2, respectively (p < 0.001), and their familiarity with anatomy and bleeding control to be 5.2 ± 3.1 and 8.2 ± 2.4, respectively (p < 0.001). At the end of the course, the mean score in response to a question about the extent to which the explanation had helped was 9.0 ± 1.9 (95% CI 8.7-9.4) and to a question about the extent to which teaching would make them feel more secure and safe was 9.2 ± 1.9 (95% CI 8.9-9.5).

CONCLUSIONS

STB course improved correct tourniquet placement, demonstrated dramatic improvements in application time, and increased levels of comfort. These findings validate the need for ongoing teaching and education.

Stop the Bleed: Is Mass Education the Best Approach?

The Stop the Bleed (STB) course teaches trainees prehospital hemorrhage control with a focus on mass education. Identifying populations most likely to benefit can help save on the significant cost and limited resources. In this study, we attempted to identify those populations and performed a cost analysis. Trainees underwent STB education and completed a survey on completion to assess demographics and prior experiences where STB skills could have been useful. Five hundred seventy-one trainees categorized as first responders (14%), students (56%), and the working public (30%) completed the survey. Most trainees found the lecture and simulation helpful, 96 per cent and 98 per cent, respectively. There were significant differences among groups who had previously been in situations where the STB course would have been helpful (88% first responders versus 40% students versus 43% public workers) ( P < 0.001). Teaching a class of 10 students costs approximately $455; the cost can be as high as $1246 for a class of 50 students. Most STB trainees found the course helpful. First responders are most likely to be exposed to situations where course information could be helpful. Focusing on specific high-yield groups rather than mass education might be a more efficient approach to STB education.

Determination of Pneumatic Tourniquet Pressure of Lower Limb by Ultrasonic Doppler

OBJECTIVE

The aim of this study was to investigate the clinical effect of tourniquet inflation pressure setting by ultrasonic Doppler on lower limb operation.

METHODS

Ninety-six patients with total knee arthroplasty were selected in this study from January 2015 to December 2015. The patients were randomly divided into the study group and the control group with 48 cases in each group. In the control group, the tourniquet pressure is determined by the doctor's request for the patient's condition, but all the tourniquet pressure values should be 80 KPa or less. In the study group, ultrasonic Doppler was used to monitor the popliteal artery blood flow of surgery limb with the maximum systolic velocity in artery as a reference value. The pressure of pneumatic tourniquet gradually increased until the maximum systolic velocity was reduced to 0. At this time, the popliteal artery blood flow was not present. The 2 groups of patients with lower extremity tourniquet pressure, hemostatic effect of intraoperative tourniquet, and the incidence of adverse reaction using tourniquets were observed and recorded.

RESULTS

In the study group, the lower extremity tourniquet pressure and the incidence of adverse reaction using tourniquets were all better than that in control group; the difference between 2 groups was significant (P < 0.05). There was no significant difference between the 2 groups in the effect of hemostasis and the time of tourniquet operation (P > 0.05).

CONCLUSIONS

The method of ultrasonic Doppler setting lower extremity tourniquet pressure during the operation could not only ensure the hemostatic effect, but it could also provide the optimum individual pneumatic tourniquet pressure value for patients. In the meanwhile, it could reduce the incidence of adverse reaction using tourniquets effectively as well as improve the safety of the tourniquet. This method played an important role in the recovery of patients.

The European guideline on management of major bleeding and coagulopathy following trauma: fifth edition

BACKGROUND

Severe traumatic injury continues to present challenges to healthcare systems around the world, and post-traumatic bleeding remains a leading cause of potentially preventable death among injured patients. Now in its fifth edition, this document aims to provide guidance on the management of major bleeding and coagulopathy following traumatic injury and encourages adaptation of the guiding principles described here to individual institutional circumstances and resources.

METHODS

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma was founded in 2004, and the current author group included representatives of six relevant European professional societies. The group applied a structured, evidence-based consensus approach to address scientific queries that served as the basis for each recommendation and supporting rationale. Expert opinion and current clinical practice were also considered, particularly in areas in which randomised clinical trials have not or cannot be performed. Existing recommendations were re-examined and revised based on scientific evidence that has emerged since the previous edition and observed shifts in clinical practice. New recommendations were formulated to reflect current clinical concerns and areas in which new research data have been generated.

RESULTS

Advances in our understanding of the pathophysiology of post-traumatic coagulopathy have supported improved management strategies, including evidence that early, individualised goal-directed treatment improves the outcome of severely injured patients. The overall organisation of the current guideline has been designed to reflect the clinical decision-making process along the patient pathway in an approximate temporal sequence. Recommendations are grouped behind the rationale for key decision points, which are patient- or problem-oriented rather than related to specific treatment modalities. While these recommendations provide guidance for the diagnosis and treatment of major bleeding and coagulopathy, emerging evidence supports the author group's belief that the greatest outcome improvement can be achieved through education and the establishment of and adherence to local clinical management algorithms.

CONCLUSIONS

A multidisciplinary approach and adherence to evidence-based guidance are key to improving patient outcomes. If incorporated into local practice, these clinical practice guidelines have the potential to ensure a uniform standard of care across Europe and beyond and better outcomes for the severely bleeding trauma patient.

Preliminary Investigation of Civilian Clinician Perspectives & Just-in-Time Guidance for Tourniquet Use to “Stop the Bleed”

Objective

The American College of Surgeons (ACS) encourages clinicians to provide training to laypeople on tourniquet application. It is unclear whether clinicians are confident in their abilities and equipped with adequate knowledge, skills, and resources. This study aimed to determine surgical trainee knowledge and attitudes regarding tourniquet application and compare the effectiveness of instructions.

Methods

Thirty surgical trainees performed a tourniquet application simulation using a Combat Application Tourniquet and one of the three instructions sets developed by ACS, Department of Homeland Security, and the tourniquet manufacturer. Participants reported tourniquet knowledge, attitudes, and confidence and discussed the instructions. One instruction set was updated and compared to the original set with 20 new trainees.

Results

Participants with ACS instructions passed the greatest number of steps (p &lt; 0.01) and completed the task significantly faster compared to those with manufacturer instructions (p &lt; 0.01). Participants (80%) reported favorable views toward tourniquets but 30–60% did not align with to ACS tourniquet guidelines. Focus group participants suggested revisions to the ACS instructions. Comparing the original and revised version of these instructions resulted in no significant improvements.

Conclusions

ACS instructions provide guidance; however, improvements to tourniquet instruction are needed for success in controlling exsanguinating hemorrhage.

Voluntary running protects against neuromuscular dysfunction following hindlimb ischemia-reperfusion in mice

Ischemia-reperfusion (IR) due to temporary restriction of blood flow causes tissue/organ damages under various disease conditions, including stroke, myocardial infarction, trauma, and orthopedic surgery. In the limbs, IR injury to motor nerves and muscle fibers causes reduced mobility and quality of life. Endurance exercise training has been shown to increase tissue resistance to numerous pathological insults. To elucidate the impact of endurance exercise training on IR injury in skeletal muscle, sedentary and exercise-trained mice (5 wk of voluntary running) were subjected to ischemia by unilateral application of a rubber band tourniquet above the femur for 1 h, followed by reperfusion. IR caused significant muscle injury and denervation at neuromuscular junction (NMJ) as early as 3 h after tourniquet release as well as depressed muscle strength and neuromuscular transmission in sedentary mice. Despite similar degrees of muscle atrophy and oxidative stress, exercise-trained mice had significantly reduced muscle injury and denervation at NMJ with improved regeneration and functional recovery following IR. Together, these data suggest that endurance exercise training preserves motor nerve and myofiber structure and function from IR injury and promote functional regeneration. NEW & NOTEWORTHY This work provides the first evidence that preemptive voluntary wheel running reduces neuromuscular dysfunction following ischemia-reperfusion injury in skeletal muscle. These findings may alter clinical practices in which a tourniquet is used to modulate blood flow.

Stop the Bleed: Does the Training Work One Month Out?

The Stop the Bleed initiative empowers and trains citizens as immediate responders, to recognize and control severe hemorrhage. We sought to determine the retention of short-term knowledge and ability to apply a Combat Application Tourniquet (CAT) in 10 nonmedical personnel. A standard “Stop the Bleed” (Bleeding Control) course was taught including CAT application. Posttraining performance was assessed at 30 days using a standardized mannequin with a traumatic below-knee amputation. Technique, time, pitfalls, and feedback were all recorded. No participant had placed a CAT before the initial class. After the initial class, self-report by a Likert scale survey revealed an increased confidence in tourniquet application from 2.4 pretraining to 4.7 posttraining. At 30 days, confidence decreased to 3.4 before testing. Six of 10 were successful at tourniquet placement. Completion time was 77.75 seconds (43–157 seconds). Successful participants reported a confidence level of 4.7 versus those unsuccessful at 3.3. The “Stop the Bleed” initiative teaches lifesaving skills to the public through a short training course. This information regarding the training of nonmedical personnel may assist in strengthening training efforts for the public. Further investigations are needed to characterize skill degradation and retention over time.

Hemodynamic consequences of extremity injuries following a terrorist bombing attack: retrospective cohort study

BACKGROUND

Extremities are commonly injured following bomb explosions. The main objective of this study was to evaluate the prevalence of hemorrhagic shock (HS) in victims of explosion suffering from extremity injuries.

METHODS

Retrospective study based on a cohort of patient records maintained in one hospital's mass casualty registry.

RESULTS

Sixty-six victims of explosion who were hospitalized with extremity injuries were identified and evaluated. Sixteen (24.2%) of these were hemodynamically unstable during the first 24 h of treatment. HS could be attributed to associated injuries in seven of the patients. In the other nine patients, extremity injury was the only injury that could explain HS in seven patients and the extremity injury was a major contributor to HS together with another associated injury in two patients. In those 9 patients, in whom the extremity injury was the sole or major contributor to HS, a median of 10 (range 2-22) pRBC was transfused during the first 24 h of treatment. Six of the nine patients were in need of massive transfusion. Fractures in both upper and lower extremities, Gustilo IIIb-c open fractures and AIS 3-4 were found to be risk factors for HS.

CONCLUSIONS

Ample consideration should be given to patients with extremity injuries due to explosions, as these may be immediately life threatening. Tourniquet use should be encouraged in the pre-hospital setting. Before undertaking surgery, emergent HS should be considered in these patients and prevented by appropriate resuscitation.

Research Gaps in Wilderness Medicine

INTRODUCTION

Wilderness medicine involves the treatment of individuals in remote, austere environments. Given the high potential for injuries as well as the unique treatment modalities required in wilderness medicine, evidence-based clinical practice guidelines are necessary to provide optimal care. In this study, we identify evidence gaps from low-quality recommendations in wilderness medicine clinical practice guidelines and identify new/ongoing research addressing them.

METHODS

We included relevant clinical practice guidelines from the Wilderness Medical Society and obtained all 1C or 2C level recommendations. Patient/Problem/Population, intervention, comparison, outcome (PICO) questions were created to address each recommendation. Using 24 search strings, we extracted titles, clinical trial registry number, and recruitment status for 8899 articles. We categorized the articles by trial design to infer the effect they may have on future recommendations.

RESULTS

Twelve clinical practice guidelines met inclusion criteria. From these we located 275 low-quality recommendations and used them to create 275 PICO questions. Thirty-three articles were relevant to the PICO questions. Heat-related illness had the highest number of relevant articles (n=9), but acute pain and altitude sickness had the most randomized clinical trials (n=6).

CONCLUSION

Overall, few studies were being conducted to address research gaps in wilderness medicine. Heat-related illness had the most new or ongoing research, whereas no studies were being conducted to address gaps in eye injuries, basic wound management, or spine immobilization. Animals, cadavers, and mannequin research are useful in cases in which human evidence is difficult to obtain. Establishing research priorities is recommended for addressing research gaps identified by guideline panels.