Prehospital advances in the management of severe penetrating trauma

Synthetic hydrogels as blood clot mimicking wound healing materials

Excessive bleeding-or hemorrhage-causes millions of civilian and non-civilian casualties every year. Additionally, wound sequelae, such as infections, are a significant source of chronic morbidity, even if the initial bleeding is successfully stopped. To treat acute and chronic wounds, numerous wound healing materials have been identified, tested, and adopted. Among them are topical dressings, such as gauzes, as well as natural and biomimetic materials. However, none of these materials successfully mimic the complex and dynamic properties of the body's own wound healing material: the blood clot. Specifically, blood clots exhibit complex mechanical and biochemical properties that vary across spatial and temporal scales to guide the wound healing response, which make them the ideal wound healing material. In this manuscript, we review blood clots' complex mechanical and biochemical properties, review current wound healing materials, and identify opportunities where new materials can provide additional functionality, with a specific focus on hydrogels. We highlight recent developments in synthetic hydrogels that make them capable of mimicking a larger subset of blood clot features: as plugs and as stimuli for tissue repair. We conclude that future hydrogel materials designed to mimic blood clot biochemistry, mechanics, and architecture can be combined with exciting platelet-like particles to serve as hemostats that also promote the biological wound healing response. Thus, we believe synthetic hydrogels are ideal candidates to address the clear need for better wound healing materials.

Battlefield Medicine: Anesthesia and Critical Care in the Combat Zone

The US Military Joint Trauma System has been developed to mitigate the harsh conditions under which medical providers care for combat casualties and provide continuity of care from the battlefield to US medical centers. We review the components of this system with emphasis on combat trauma care under fire and the role of the anesthesiologist and intensivist in this continuum of care. An important link in the chain of survival is the Air Force Critical Care Aeromedical Transport Team, which provides critical care while transporting casualties from the theater to higher levels of care outside the war zone and home.

Metabolic Profiling of a Porcine Combat Trauma-Injury Model Using NMR and Multi-Mode LC-MS Metabolomics-A Preliminary Study

Profiles of combat injuries worldwide have shown that penetrating trauma is one of the most common injuries sustained during battle. This is usually accompanied by severe bleeding or hemorrhage. If the soldier does not bleed to death, he may eventually succumb to complications arising from trauma hemorrhagic shock (THS). THS occurs when there is a deficiency of oxygen reaching the organs due to excessive blood loss. It can trigger massive metabolic derangements and an overwhelming inflammatory response, which can subsequently lead to the failure of organs and possibly death. A better understanding of the acute metabolic changes occurring after THS can help in the development of interventional strategies, as well as lead to the identification of potential biomarkers for rapid diagnosis of hemorrhagic shock and organ failure. In this preliminary study, a metabolomic approach using the complementary platforms of nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography coupled with mass spectrometry (LC-MS) was used to determine the metabolic changes occurring in a porcine model of combat trauma injury comprising of penetrating trauma to a limb with hemorrhagic shock. Several metabolites associated with the acute-phase reaction, inflammation, energy depletion, oxidative stress, and possible renal dysfunction were identified to be significantly changed after a thirty-minute shock period.

Radiografía de tórax de control en pacientes con neumotórax postraumático asintomático

Introducción. El trauma de tórax tiene alta incidencia y el neumotórax es el hallazgo más frecuente. La literatura es escasa sobre qué hacer con los pacientes asintomáticos y con neumotórax por trauma de tórax penetrante. El objetivo de este estudio fue evaluar cuáles son los hallazgos de la radiografía de control de los pacientes con trauma de tórax penetrante que no son llevados inicialmente a cirugía, y su utilidad para determinar la necesidad de un tratamiento adicional. Métodos. Se realizó un estudio retrospectivo de cohorte, incluyendo pacientes mayores de 15 años que ingresaron por trauma de tórax penetrante entre enero de 2015 y diciembre de 2017 y que no requirieron manejo quirúrgico inicial. Se analizaron los resultados de la radiografía de tórax, el tiempo de su toma y la conducta decidida según los hallazgos en los pacientes dejados inicialmente bajo observación. Resultados. Se incluyeron 1.554 pacientes, cuya edad promedio fue de 30 años, 92,5 % del sexo masculino y 97% con herida por arma cortopunzante. Se dejaron 361 pacientes bajo observación con radiografía de control, de los cuales 186 (51,5 %) no presentaban alteraciones en su radiografía inicial, 142 tenían neumotórax menor del 30 % y 33 tenían neumotórax mayor del 30 %, hemoneumotórax o hemotórax. Se requirió toracostomía cerrada como conducta final en 78 casos, esternotomía o toracotomía en 2 casos y 281 se dieron de alta. Conclusión. En pacientes asintomáticos con neumotórax pequeño o moderado y sin otras lesiones significativas, podrían ser innecesarios los largos tiempos de observación, las radiografías y la toracostomía cerrada.

Five years of prolonged field care: prehospital challenges during recent French military operations

BACKGROUND

French military operations in the Sahel conducted since 2013 over more than 5 million square kilometers have challenged the French Military Health Service with specific problems in prolonged field care.

STUDY DESIGN AND METHODS

To describe these challenges, we retrospectively analyzed the prehospital data from the first 5 years of these operations within a delimited area.

RESULTS

One hundred eighty-three servicemen of different nationalities were evacuated, mainly as a result of explosions (73.2%) or gunshots (21.9%). Their mean number evacuation was 2.2 (minimum, 1; maximum, 8) per medical evacuation with a direct evacuation from the field to a Role 2 medical treatment facility (MTF) for 62% of them. For the highest-priority casualties (N = 46), the median time [interquartile range] from injury to a Role 2 MTF was 130 minutes [70 minutes to 252 minutes], exceeding 120 minutes in 57% of cases and 240 minutes in 26%. The most frequent out-of-hospital medical interventions were external hemostasis, airway and hemopneumothorax management, hypotensive resuscitation, analgesia, immobilization, and antibiotic administration. Prehospital transfusion (RBCs and/or lyophilized plasma) was started three times in the field, two times during helicopter medical evacuation, and five times in tactical fixed wing medical aircraft. Lyophilized plasma was confirmed to be particularly suitable in these settings. One of the specific issues involved in lengthy prehospital time was the importance to reassess and convert tourniquets prior to Role 2 MTF admission.

CONCLUSION

Main challenges identified include reducing evacuation times as much as possible, preserving ground deployment of sufficiently trained medics and medical teams, optimization of transfusion strategies, and strengthening specific prolonged field care equipment and training.

Intravenous Hydroxocobalamin Versus Hextend Versus Control for Class III Hemorrhage Resuscitation in a Prehospital Swine Model

Background

Hydroxyethyl starch (Hextend) has been used for hemorrhagic shock resuscitation, however, hydroxyethyl starch may be associated with adverse outcomes.

Objective

To compare systolic blood pressure (sBP) in animals that had 30% of their blood volume removed and treated with intravenous hydroxocobalamin, hydroxyethyl starch, or no fluid.

Methods

Twenty-eight swine (45-55 kg) were anesthetized and instrumented with continuous femoral and pulmonary artery pressure monitoring. Animals were hemorrhaged 20 mL/kg over 20 minutes and then administered 150 mg/kg IV hydroxocobalamin in 180 mL saline, 500 mL hydroxyethyl starch, or no fluid and monitored for 60 minutes. Data were modeled using repeated measures multivariate analysis of variance.

Results

There were no significant differences before treatment. At 20 minutes after hemorrhage, there was no significant difference in mean sBP between treated groups, however, control animals displayed significantly lower mean sBP (p < 0.001). Mean arterial pressure and heart rate improved in the treated groups but not in the control group (p < 0.02). Prothrombin time was longer and platelet counts were lower in the Hextend group (p < 0.05). Moreover, thromboelastography analysis showed longer clotting (K) times (p < 0.05) for the hydroxyethyl starch-treated group.

Conclusion

Hydroxocobalamin restored blood pressure more effectively than no treatment and as effectively as hydroxyethyl starch but did not adversely affect coagulation.

Study protocol of a randomised controlled trial of intranasal ketamine compared with intranasal fentanyl for analgesia in children with suspected, isolated extremity fractures in the paediatric emergency department

INTRODUCTION

Fentanyl is the most widely studied intranasal (IN) analgesic in children. IN subdissociative (INSD) ketamine may offer a safe and efficacious alternative to IN fentanyl and may decrease overall opioid use during the emergency department (ED) stay. This study examines the feasibility of a larger, multicentre clinical trial comparing the safety and efficacy of INSD ketamine to IN fentanyl and the potential role for INSD ketamine in reducing total opioid medication usage.

METHODS AND ANALYSIS

This double-blind, randomised controlled, pilot trial will compare INSD ketamine (1 mg/kg) to IN fentanyl (1.5 μg/kg) for analgesia in 80 children aged 4-17 years with acute pain from a suspected, single extremity fracture. The primary safety outcome for this pilot trial will be the frequency of cumulative side effects and adverse events at 60 min after drug administration. The primary efficacy outcome will be exploratory and will be the mean reduction of pain scale scores at 20 min. The study is not powered to examine efficacy. Secondary outcome measures will include the total dose of opioid pain medication in morphine equivalents/kg/hour (excluding study drug) required during the ED stay, number and reason for screen failures, time to consent, and the number and type of protocol deviations. Patients may receive up to 2 doses of study drug.

ETHICS AND DISSEMINATION

This study was approved by the US Food and Drug Administration, the local institutional review board and the study data safety monitoring board. This study data will be submitted for publication regardless of results and will be used to establish feasibility for a multicentre, non-inferiority trial.

TRIAL REGISTRATION NUMBER

NCT02521415.

Needle decompression of tension pneumothorax: Population-based epidemiologic approach to adequate needle length in healthy volunteers in Northeast Germany

BACKGROUND

Tension pneumothorax is one of the leading causes of preventable death in both military and civilian trauma patients. Needle decompression is recommended in trauma guidelines as an emergency procedure to relieve increased intrapleural pressure. The main reason for decompression failure is reported to be insufficient needle length in proportion to the chest wall thickness (CWT). So far, population-based epidemiologic data on CWT are missing. Therefore, it was the aim of this work to investigate the CWT in the second intercostal space, midclavicular line, based on magnetic resonance imaging data of a large population-based sample. The second aim of this study was to explore the potential risk of iatrogenic lesions caused by the proximity of the intended puncture track to the internal mammary artery.

METHODS

A total of 2,574 healthy volunteers (mean [SD] age, 53.3 [13.9] years; range, 21-89 years) from the population-based cohort Study of Health in Pomerania (SHIP) were enrolled. CWT and the distance from the intended puncture track to the internal mammary artery were investigated with the chest sequences of a standardized 1.5-T whole-body magnetic resonance imaging.

RESULTS

For all 5,148 measured sites in 2,574 volunteers, the mean (SD) CWT was 5.1 (1.4) cm. The mean body mass index was determined to be 27.7 kg/m. The CWT correlated significantly with body weight and body mass index. The internal mammary artery was located medial to the intended puncture site in all participants; the mean (SD) distance was 5.7 (0.7) cm on the right and 5.5 (0.7) cm on the left side.

CONCLUSION

Based on the population-based epidemiologic data presented in this study, the use of a needle of 7 cm in length is recommended to decompress a tension pneumothorax in the second intercostal space in the midclavicular line, which might successfully decompress more than 90% of the participants in this study. When using this anterior approach at the anatomically correct puncture site, safety margin to the internal mammary artery is sufficient so that the risk of iatrogenic lesion of the internal mammary artery should be minimal.

LEVEL OF EVIDENCE

Therapeutic/care management study, level IV.

The effect of CoolClot hemostatic agent on skin wound healing in rats

BACKGROUND

Hemostatic agents can play a key role in controlling severe hemorrhage after trauma. Previously, some criteria have been defined for improving the quality of these products; one of them is that the hemostat causes no further tissue injury. CoolClot is a recently introduced hemostatic agent that its effects on wound healing have not yet been examined, which this study aims to address.

MATERIALS AND METHODS

Thirty-four adult male Sprague-Dawley rats were assigned randomly to two groups (n = 17): a study group where CoolClot hemostatic agent was applied on their wounds, and a control group whose wounds were washed only with sterile saline. The rats underwent dorsal full-thickness skin excisional wounds (20 mm diameter). On day 12 after wounding, seven rats were chosen in a random manner from each of the groups of study and control, and their skin biopsies from the wound sites were sent for histologic examination. Skin samples of the remaining rats in each group were taken on the 21st d after wound creation. Wound healing was also monitored photographically. In addition, wound surface temperature after wounding, and the application of CoolClot was recorded.

RESULTS

There was no significant difference between the groups of study and control regarding the examined histopathologic parameters. The maximum increase in wound surface temperature was 1.56°C.

CONCLUSIONS

One-time topical usage of CoolClot has no significant negative effect on the wound healing process. In addition, no significant increase in wound surface temperature will occur after the application of this agent.

First Aid and Transportation Course Contents Based on Experience gained in the Iran-Iraq War: a Qualitative Study

BACKGROUND

Effective first aid and transportation influences injury-induced mortality. But few qualitative studies have been conducted so far in this area.

OBJECTIVES

The aim of this study was to identify the content of the first aid and patient transportation course based on experience gained from the Iran-Iraq war.

PATIENTS AND METHODS

This was a conventional qualitative content analysis study; a purposeful sample of 14 first aid and transportation experts who had worked during the Iran-Iraq war was recruited. We collected and analyzed the study data by using the semi-structured interview method and the conventional content analysis approach respectively. Each interview transcript was reviewed several times. Words, sentences, and paragraphs were labeled with codes. Codes were compared with each other and categorized according to their similarities. Similar sub-categories and categories were also grouped together and formed themes.

RESULTS

Study participants' experiences of wartime first aid and transportation (FAT) education fell into two main themes including 'the congruence of education and educational needs' and 'managers' engagement in FAT education. The four main categories of these two themes were use of appropriate educational facilities, adopting effective teaching strategies, universal FAT education and specialized training skills.

CONCLUSIONS

The two key requirements of the first aid and transportation courses are practicality and managerial engagement. We developed and provided specific guidance of FAT curriculum by using the study findings. This curriculum is recommended for educating FAT staffs, paramedics, emergency technicians, and military nurses.

A prospective, randomized trial of intravenous hydroxocobalamin versus whole blood transfusion compared to no treatment for Class III hemorrhagic shock resuscitation in a prehospital swine model

OBJECTIVES

The objective was to compare systolic blood pressure (sBP) over time in swine that have had 30% of their blood volume removed (Class III shock) and treated with intravenous (IV) whole blood or IV hydroxocobalamin, compared to nontreated control animals.

METHODS

Thirty swine (45 to 55 kg) were anesthetized, intubated, and instrumented with continuous femoral and pulmonary artery pressure monitoring. Animals were hemorrhaged a total of 20 mL/kg over a 20-minute period. Five minutes after hemorrhage, animals were randomly assigned to receive 150 mg/kg IV hydroxocobalamin solubilized in 180 mL of saline, 500 mL of whole blood, or no treatment. Animals were monitored for 60 minutes thereafter. A sample size of 10 animals per group was determined based on a power of 80% and an alpha of 0.05 to detect an effect size of at least a 0.25 difference (>1 standard deviation) in mean sBP between groups. sBP values were analyzed using repeated-measures analysis of variance (RANOVA). Secondary outcome data were analyzed using repeated-measures multivariate analysis of variance (RMANOVA).

RESULTS

There were no significant differences between hemodynamic parameters of IV hydroxocobalamin versus whole blood versus control group at baseline (MANOVA; Wilks' lambda; p = 0.868) or immediately posthemorrhage (mean sBP = 47 mm Hg vs. 41 mm Hg vs. 37 mm Hg; mean arterial pressure = 39 mm Hg vs. 28 mm Hg vs. 34 mm Hg; mean serum lactate = 1.2 mmol/L vs. 1.4 mmol/L vs. 1.4 mmol/L; MANOVA; Wilks' lambda; p = 0.348). The outcome RANOVA model detected a significant difference by time between groups (p < 0.001). Specifically, 10 minutes after treatment, treated animals showed a significant increase in mean sBP compared to nontreated animals (mean sBP = 76.3 mm Hg vs. 85.7 mm Hg vs. 51.1 mm Hg; p < 0.001). RMANOVA modeling of the secondary data detected a significant difference in mean arterial pressure, heart rate, and serum lactate (p < 0.001). Similar to sBP, 10 minutes after treatment, treated animals showed a significant increase in mean arterial pressure compared to nontreated animals (mean arterial pressure = 67.7 mm Hg vs. 61.4 mm Hg vs. 40.5 mm Hg). By 10 minutes, mean heart rate was significantly slower in treated animals compared to nontreated animals (mean heart rate = 97.3 beats/min vs. 95.2 beats/min vs. 129.5 beats/min; p < 0.05). Serum lactate, an early predictor of shock, continued to rise in the control group, whereas it did not in treated animals. Thirty minutes after treatment, serum lactate values of treated animals were significantly lower compared to nontreated animals (p < 0.05). This trend continued throughout the 60-minute observation period such that 60-minute values for lactate were 1.4 mmol/L versus 1.1 mmol/L versus 3.8 mmol/L. IV hydroxocobalamin produced a statistically significant increase in systemic vascular resistance compared to control, but not whole blood, with a concomitant decrease in cardiac output.

CONCLUSIONS

Intravenous hydroxocobalamin was more effective than no treatment and as effective as whole blood transfusion, in reversing hypotension and inhibiting rises in serum lactate in this prehospital, controlled, Class III swine hemorrhage model.

Celox-coated gauze for the treatment of civilian penetrating trauma: a randomized clinical trial

Background:

Uncontrolled hemorrhage is a well-recognized cause of mortality in trauma victims and the control of active hemorrhage is among the initial steps in resuscitation.

Objectives:

The purpose of this study was to assess the role of a hemostatic agent “celox” in the management of civilian stab-wound trauma.

Patients and Methods:

In this clinical trial study, 160 patients with penetrating limb trauma were randomly allocated to either the control or intervention group (n = 80, each group). Controls were treated with the simple pressure dressing, while the celox-coated gauze was used in the intervention group. The time for achievement of hemostasis and the amount of bleeding were recorded. Data were analyzed using SPSS Version 21 and Stata 13. A P value of less than 0.05 was considered statistically significant.

Results:

The mean age of participants was 30.5 and the majority of patients were male (90.6%). The forearm and distal leg were the most sites of injury. Hemostasis was achieved within 5 minutes in 32.5% of the control group and 51.3% of the intervention group. Using the celox-coated gauze significantly reduced the time to hemostasis (P = 0.01). Moreover, the blood loss was significantly lower in the celox group compared to the controls (P < 0.05).

Conclusions:

Using the celox-coated gauze is able to achieve hemostasis in penetrating limb trauma faster than the conventional pressure bandage. Further research is required to clarify the subset of patients who will benefit the most from this effect in the emergency department.

Emergency Medical Services Response to Active Shooter Incidents: Provider Comfort Level and Attitudes Before and After Participation in a Focused Response Training Program

Introduction

Emergency Medical Services (EMS) routinely stage in a secure area in response to active shooter incidents until the scene is declared safe by law enforcement. Due to the time-sensitive nature of injuries at these incidents, some EMS systems have adopted response tactics utilizing law enforcement protection to expedite life-saving medical care.

Objective

Describe EMS provider perceptions of preparedness, adequacy of training, and general attitudes toward active shooter incident response after completing a tactical awareness training program.

Methods

An unmatched, anonymous, closed-format survey utilizing a five-point Likert scale was distributed to participating EMS providers before and after a focused training session on joint EMS/police active shooter rescue team response. Descriptive statistics were used to compare survey results. Secondary analysis of responses based on prior military or tactical medicine training was performed using a chi-squared analysis.

Results

Two hundred fifty-six providers participated with 88% (225/256) pretraining and 88% (224/256) post-training surveys completed. Post-training, provider agreement that they felt adequately prepared to respond to an active shooter incident changed from 41% (92/225) to 89% (199/224), while agreement they felt adequately trained to provide medical care during an active shooter incident changed from 36% (82/225) to 87% (194/224). Post-training provider agreement that they should never enter a building with an active shooter changed from 73% (165/225) to 61% (137/224). Among the pretraining surveys, significantly more providers without prior military or tactical experience agreed they should never enter a building with an active shooter until the scene was declared safe (78% vs 50%, P = .002), while significantly more providers with prior experience felt both adequately trained to provide medical care in an active shooter environment (56% vs 31%, P = .007) and comfortable working jointly with law enforcement within a building if a shooter were still inside (76% vs 56%, P = .014). There was no difference in response to these questions in the post-training survey.

Conclusions

Attitudes and perceptions regarding EMS active shooter incident response appear to change among providers after participation in a focused active shooter response training program. Further studies are needed to determine if these changes are significant and whether early EMS response during an active shooter incident improves patient outcomes.

JonesJ, KueR, MitchellP, EblanG, DyerKS. Emergency Medical Services response to active shooter incidents: provider comfort level and attitudes before and after participation in a focused response training program. Prehosp Disaster Med. 2014;29(4):1-7.

3 Echo: Concept of Operations for Early Care and Evacuation of Victims of Mass Violence

This report describes the successful use of a simple 3-phase approach that guides the initial 30 minutes of a response to blast and active shooter events with casualties: Enter, Evaluate, and Evacuate (3 Echo) in a mass-shooting event occurring in Minneapolis, Minnesota USA, on September 27, 2012. Early coordination between law enforcement (LE) and rescue was emphasized, including establishment of unified command, a common operating picture, determination of evacuation corridors, swift victim evaluation, basic treatment, and rapid evacuation utilizing an approach developed collaboratively over the four years prior to the event. Field implementation of 3 Echo requires multi-disciplinary (Emergency Medical Services (EMS), fire and LE) training to optimize performance. This report details the mass-shooting event, the framework created to support the response, and also describes important aspects of the concepts of operation and curriculum evolved through years of collaboration between multiple disciplines to arrive at unprecedented EMS transport times in response to the event.

AutreyAW, HickJL, BramerK, BerndtJ, BundtJ. 3 Echo: concept of operations for early care and evacuation of victims of mass violence. Prehosp Disaster Med. 2014;29(4):1-8.

A structured autopsy-based audit of 370 firearm fatalities: Contribution to inform policy decisions and the probability of the injured arriving alive at a hospital and receiving definitive care

The objectives of this autopsy-based audit of firearm-related fatalities were to acquire data to inform policy decisions and to assess the probability of the injured arriving alive at a hospital and receiving definitive care.

EVALUATED VARIABLES

Demographics; co-morbidities; location and intention of the injury; toxicology; types of firearms; Abbreviated Injury Scale; Injury Severity Score (ISS); transfer means and time; and location of death.

RESULTS

Of a total of 370 fatalities, 85.7% were male. The median age was 38 (9-95) years. Suicides (47%) and assaults (45.1%) were the most common underlying intentions. The most seriously injured regions were the head (44.5%), thorax (25.7%), abdomen (10.7%), and spine (5.7%). Of the 370 total subjects, 4.9% had an ISS<16 and 59.5% had an ISS≤74; both groups were classified as potentially preventable deaths. The majority (84%) died at the scene, and only 9.8% left the emergency department alive for further treatment. Multivariate analyses documented that postmortem ISS is an independent factor that predicts the probability of the injured reaching a hospital alive and receiving definitive care. Individuals injured in greater Athens and those most seriously injured in the face, abdomen or spine had significantly greater chances of reaching a hospital alive and receiving definitive care, whereas those injured by a shotgun and the positive toxicology group were significantly less likely to. In conclusion, this study provides data to inform policy decisions, calls for a surveillance network and establishes a baseline for estimating the probability regarding the location of firearm-related deaths.

Prehospital interventions performed in a combat zone: a prospective multicenter study of 1,003 combat wounded

BACKGROUND

Battlefield care given to a casualty before hospital arrival impacts clinical outcomes. To date, the published data regarding care given in the prehospital setting of a combat zone are limited. The purpose of this study was to describe the incidence and efficacy of specific prehospital lifesaving interventions (LSIs; interventions that could affect the outcome of the casualty), consistent with the Tactical Combat Casualty Care paradigm, performed during the resuscitation of casualties in a combat zone.

METHODS

We performed a prospective observational study between November 2009 and November 2011. Casualties were enrolled as they were treated at six US surgical facilities in Afghanistan. Descriptive data were collected on a standardized data collection form and included mechanism of injury, airway management, chest and hemorrhage interventions, vascular access, type of fluid administered, and hypothermia prevention. On arrival to the military hospital, the treating physician determined whether an intervention was performed correctly and whether an intervention was not performed that should have been performed (missed LSI).

RESULTS

A total of 1,003 patients met the inclusion criteria. Their mean (SD) age was 25 (8.5) years and 97% were male. The mechanism of injury was explosion in 60% of patients, penetrating in 24% of patients, blunt in 15% of patients, and burn in 0.8% of patients. The most commonly performed LSIs included hemorrhage control (n = 599), hypothermia prevention (n = 429), and vascular access (n = 388). Of the missed LSIs, 252 were identified with the highest percentage of missed opportunities being composed of endotracheal intubation, chest needle decompression, and hypotensive resuscitation. In contrast, tourniquet application had the lowest percentage of missed opportunities.

CONCLUSIONS

In our prospective study of prehospital LSIs performed in a combat zone, we observed a higher rate of incorrectly performed and missed LSIs in airway and chest (breathing) interventions than hemorrhage control interventions. The most commonly performed LSIs had lower incorrect and missed LSI rates.

Hextend and 7.5% hypertonic saline with Dextran are equivalent to Lactated Ringer's in a swine model of initial resuscitation of uncontrolled hemorrhagic shock

BACKGROUND

The optimal fluid strategy for the early treatment of trauma patients remains highly debated. Our objective was to determine the efficacy of an initial bolus of resuscitative fluids used in military and civilian settings on the physiologic response to uncontrolled hemorrhagic shock in a prospective, randomized, blinded animal study.

METHODS

Fifty anesthetized swine underwent central venous and arterial catheterization followed by celiotomy. Grade V liver injury was performed, followed by 30 minutes of uncontrolled hemorrhage. Then, liver packing was completed, and fluid resuscitation was initiated over 12 minutes with 2 L normal saline (NS), 2 L Lactated Ringer's (LR), 250 mL 7.5% hypertonic saline with 3% Dextran (HTS), 500 mL Hextend (HEX), or no fluid (NF). Animals were monitored for 2 hours postinjury. Blood loss after initial hemorrhage, mean arterial pressure (MAP), tissue oxygen saturation (StO2), hematocrit, pH, base excess, and lactate were measured at baseline, 1 hour, and 2 hours.

RESULTS

NF group had less post-treatment blood loss compared with other groups. MAP and StO2 for HEX, HTS, and LR at 1 hour and 2 hours were similar and higher than NF. MAP and StO2 did not differ between NS and NF, but NS resulted in decreased pH and base excess.

CONCLUSIONS

Withholding resuscitative fluid results in the least amount of posttreatment blood loss. In clinically used volumes, HEX and HTS are equivalent to LR with regard to physiologic outcomes and superior to NF. NS did not provide a measurable improvement in outcome compared with NF and resulted in increased acidosis.

Needle decompression for tension pneumothorax in Tactical Combat Casualty Care: do catheters placed in the midaxillary line kink more often than those in the midclavicular line?

BACKGROUND

Tactical Combat Casualty Care (TCCC) is a system of prehospital trauma care designed for the combat environment. Needle decompression (ND) is a critical TCCC intervention, because previous data suggest that up to 33% of all preventable deaths on the battlefield result from tension pneumothoraces. There has recently been increased interest in performing ND at the fifth intercostal space in the midaxillary line to prevent complications associated with landmarking second intercostal space in the midclavicular line site. We developed a model to assess whether catheters placed in the midaxillary line for decompressing tension pneumothoraces are more prone to kinking than those placed in the midclavicular line because of adducted arms during military transport.

METHODS

To simulate ND, we secured segments of porcine chest walls over volunteer soldiers' chests and placed 14-gauge, 1.5-inch angiocatheters through the porcine wall segments which were affixed to either the midaxillary or midclavicular location on the volunteers. We then assessed for occlusion and kinking by flow of normal saline (NS) through the angiocatheter in situ. The angiocatheter was then transduced using standard arterial line manometry, and the opening pressures required to initiate flow through the catheters were measured. The opening pressures were then converted to mm Hg. We also assessed for catheter occlusion after the physical manipulation of the patient, by simulated patient transport.

RESULTS

We observed that there was a significant pressure difference required to achieve free flow through the in situ angiocatheter between the fifth intercostal space midaxillary line versus the second intercostal space midclavicular line site (13.1 ± 3.6 mm Hg vs. 7.9 ± 1.8 mm Hg).

CONCLUSIONS

This study suggests that the 14-gauge, 1.5-inch angiocatheter used for ND in the midaxillary line may partially and temporarily occlude in patients who will be transported on military stretchers. The pressure of 12.8 mm Hg has been documented in animal models as the pressure at which hemodynamic instability develops. This may contribute to the reaccumulation of tension pneumothoraces and ultimate patient deterioration in military transport.

Clinical review: Canadian National Advisory Committee on Blood and Blood Products--Massive transfusion consensus conference 2011: report of the panel

In June 2011 the Canadian National Advisory Committee on Blood and Blood Products sponsored an international consensus conference on transfusion and trauma. A panel of 10 experts and two external advisors reviewed the current medical literature and information presented at the conference by invited international speakers and attendees. The Consensus Panel addressed six specific questions on the topic of blood transfusion in trauma. The questions focused on: ratio-based blood resuscitation in trauma patients; the impact of survivorship bias in current research conclusions; the value of nonplasma coagulation products; the role of protocols for delivery of urgent transfusion; the merits of traditional laboratory monitoring compared with measures of clot viscoelasticity; and opportunities for future research. Key findings include a lack of evidence to support the use of 1:1:1 blood component ratios as the standard of care, the importance of early use of tranexamic acid, the expected value of an organized response plan, and the recommendation for an integrated approach that includes antifibrinolytics, rapid release of red blood cells, and a foundation ratio of blood components adjusted by results from either traditional coagulation tests or clot viscoelasticity or both. The present report is intended to provide guidance to practitioners, hospitals, and policy-makers.

Early hospital care of severe traumatic brain injury

Head injury is one of the major causes of trauma-related morbidity and mortality in all age groups in the United Kingdom, and anaesthetists encounter this problem in many areas of their work. Despite a better understanding of the pathophysiological processes following traumatic brain injury and a wealth of research, there is currently no specific treatment. Outcome remains dependant on basic clinical care: management of the patient's airway with particular attention to preventing hypoxia; avoidance of the extremes of lung ventilation; and the maintenance of adequate cerebral perfusion, in an attempt to avoid exacerbating any secondary injury. Hypertonic fluids show promise in the management of patients with raised intracranial pressure. Computed tomography scanning has had a major impact on the early identification of lesions amenable to surgery, and recent guidelines have rationalised its use in those with less severe injuries. Within critical care, the importance of controlling blood glucose is becoming clearer, along with the potential beneficial effects of hyperoxia. The major improvement in outcome reflects the use of protocols to guide resuscitation, investigation and treatment and the role of specialist neurosciences centres in caring for these patients. Finally, certain groups are now recognised as being at greater risk, in particular the elderly, anticoagulated patient.

Outcome after vascular trauma in a deployed military trauma system

Background

Military injuries to named blood vessels are complex limb- and life-threatening wounds that pose significant difficulties in prehospital and surgical management. The aim of this study was to provide a comprehensive description of the epidemiology, treatment and outcome of vascular injury among service personnel deployed on operations in Afghanistan and Iraq.

Methods

Data from the British Joint Theatre Trauma Registry were combined with hospital records to review all cases of vascular trauma in deployed service personnel over a 5-year interval ending in January 2008.

Results

Of 1203 injured service personnel, 110 sustained injuries to named vessels; 66 of them died before any surgical intervention. All 25 patients who sustained an injury to a named vessel in the abdomen or thorax died; 24 did not survive to undergo surgery and one casualty in extremis underwent a thoracotomy, but died. Six of 17 patients with cervical vascular injuries survived to surgical intervention; two died after surgery. Of 76 patients with extremity vascular injuries, 37 survived to surgery with one postoperative death. Interventions on 38 limbs included 19 damage control procedures (15 primary amputations, 4 vessel ligations) and 19 definitive limb revascularization procedures (11 interposition vein grafts, 8 direct repairs), four of which failed necessitating three amputations.

Conclusion

In operable patients with extremity injury, amputation or ligation is often required for damage control and preservation of life. Favourable limb salvage rates are achievable in casualties able to withstand revascularization. Despite marked progress in contemporary battlefield trauma care, torso vascular injury is usually not amenable to surgical intervention.

Trauma systems and early management of severe injuries in Scandinavia: review of the current state

INTRODUCTION

Scandinavian countries face common challenges in trauma care. It has been suggested that Scandinavian trauma system development is immature compared to that of other regions. We wanted to assess the current status of Scandinavian trauma management and system development.

METHODS

An extensive search of the Medline/Pubmed, EMBASE and SweMed+ databases was conducted. Wide coverage was prioritized over systematic search strategies. Scandinavian publications from the last decade pertaining to trauma epidemiology, trauma systems and early trauma management were included.

RESULTS

The incidence of severe injury ranged from 30 to 52 per 100,000 inhabitants annually, with about 90% due to blunt trauma. Parts of Scandinavia are sparsely populated with long pre-hospital distances. In accordance with other European countries, pre-hospital physicians are widely employed and studies indicate that this practice imparts a survival benefit to trauma patients. More than 200 Scandinavian hospitals receive injured patients, increasingly via multidisciplinary trauma teams. Challenges remain concerning pre-hospital identification of the severely injured. Improved triage allows for a better match between patient needs and the level of resources available. Trauma management is threatened by the increasing sub-specialisation of professions and institutions. Scandinavian research is leading the development of team- and simulation-based trauma training. Several pan-Scandinavian efforts have facilitated research and provided guidelines for clinical management.

CONCLUSION

Scandinavian trauma research is characterised by an active collaboration across countries. The current challenges require a focus on the role of traumatology within an increasingly fragmented health care system. Regional networks of predictable and accountable pre- and in-hospital resources are needed for efficient trauma systems. Successful development requires both novel research and scientific assessment of imported principles of trauma care.

Emerging therapies in traumatic hemorrhage control

PURPOSE OF REVIEW

Care of the injured patient is a dynamic process. Hemorrhage remains the primary cause of preventable death after trauma. Rapid and effective early care can improve survival and outcomes. Emerging therapies to address traumatic hemorrhage will be discussed.

RECENT FINDINGS

Current concepts in trauma care include damage control resuscitation with rapid surgical correction of bleeding; prevention of the development of the lethal triad; limitation of crystalloid administration and application of high ratios of plasma and platelets to packed red blood cells. Prehospital resuscitation strategies can effect care of the hemorrhaging trauma patient, as well. The goal should be to preserve vital functions without increasing the risk for further bleeding. The concept of hypotensive resuscitation has been formulated to address this issue. The type of resuscitation fluid also plays an important role, with novel fluids currently being studied for routine use. Compressible hemorrhage constitutes an important component of potentially survivable injury. Hemostatic dressings and tourniquets can prove essential to the management of combat and civilian wounds.

SUMMARY

Given the potential to preserve life with appropriate attention applied to the bleeding trauma victim, it is vitally important to explore the options currently available and continue to make improvements in care.