Minimum depths to essential structures in a UK military population using computed tomography: application to stab-resistant body armour.

INTRODUCTION: Edged weapons are a known domestic threat to the police forces of the UK. This threat is mitigated by wearing stab-resistant body armour that is either worn overtly or covertly depending on role. Although the UK military have traditionally focused their body armour design upon ballistic and fragmentation threats, future roles may require protection against an edged weapon threat. Since 2017, UK police body armour requirements for anatomical coverage for both edged weapon and ballistic threats are now based upon the requirements of UK military. This revised coverage may need additional research to determine minimum distances to essential structures. METHOD: Three entry locations and penetration vectors were chosen using the limited available information in the literature, in combination with a specialist in edged weapons defence. One hundred twenty CT trauma scans of male military service personnel were subsequently analysed to ascertain minimum distances from skin surface to the first structure encountered that is included in essential coverage (heart, aorta, vena cava, liver and spleen) at 3 specific entry points. RESULTS: Individuals ranged between 18 and 46 years, with a mean body mass index of 24.8. The absolute minimum depth from skin surface to a structure within the auspice of essential coverage was 17 mm to the liver in entry point 3 and 19 mm to the heart in entry point 2. CONCLUSIONS: Minimum distances to critical structures were significantly larger than those described in previous studies on civilians. This study will be used to supplement existing evidence to support existing UK police requirements for stab-resistant body armour. Using the weapon entry sites and vectors described in this study, overmatching to a behind armour depth of 17 mm would cover all of this population in this study.

Edged weapons awareness.

Edged weapons (sometimes referred to as sharp weapons or blades) are an increasing threat to military personnel, the blue light community (police, ambulance, firefighters, other first responders) and the general public worldwide. The use of edged weapons in criminal and terrorist incidents internationally means the forensic community needs an awareness of the technology of edged weapons, how they are used, the damage (clothing and wounding) that might be caused and any other forensic implications. In this paper, the magnitude of the problem is presented, prior research summarised and implications for forensic investigations discussed.

The use of gelatine in wound ballistics research.

Blocks of gelatine are used in both lethality and survivability studies for broadly the same reason, i.e. comparison of ammunition effects using a material that it is assumed represents (some part of) the human body. The gelatine is used to visualise the temporary and permanent wound profiles; elements of which are recognised as providing a reasonable approximation to wounding in humans. One set of researchers aim to improve the lethality of the projectile, and the other to understand the effects of the projectile on the body to improve survivability. Research areas that use gelatine blocks are diverse and include ammunition designers, the medical and forensics communities and designers of ballistic protective equipment (including body armour). This paper aims to provide an overarching review of the use of gelatine for wound ballistics studies; it is not intended to provide an extensive review of wound ballistics as that already exists, e.g. Legal Med 23:21-29, 2016. Key messages are that test variables, projectile type (bullet, fragmentation), impact site on the body and intermediate layers (e.g. clothing, personal protective equipment (PPE)) can affect the resulting wound profiles.

Neuropathic pain treatment and research: experiences from the United Kingdom mission to Afghanistan and future prospects.

The Defence Medical Services (DMS) of the United Kingdom (UK) assumed command of the Role 3 Medical Treatment Facility field hospital during Operation HERRICK in Afghanistan from April 2006 until the final drawdown in November 2014. The signature injury sustained by coalition personnel during this period was traumatic amputation from improvised explosive devices. Many patients who had suffered extensive tissue damage experienced both nociceptive and neuropathic pain (NeuP). This presented as a heterogeneous collection of symptoms that are resistant to treatment. This paper discusses the relationship of NeuP in the context of ballistic injury, drawing in particular on clinical experience from the UK mission to Afghanistan, Operation HERRICK. The role of this paper is to describe the difficulties of assessment, treatment and research of NeuP and make recommendations for future progress within the DMS.

Use of illuminance as a guide to effective light delivery during daylight photodynamic therapy in the U.K.

BACKGROUND: Daylight PDT (dPDT) is an effective and nearly painless treatment for field-change actinic keratosis. Measuring the protoporphyrin-IX (PpIX)-weighted exposure dose can give an indication of when conditions are most viable for effective dPDT. It would be advantageous for practitioners if more detailed information of exposure dose and appropriate treatment conditions were available. Where sophisticated measurement equipment is unavailable, simpler and more cost-effective methods of dose measurement are desirable. OBJECTIVES: To devise a model whereby illuminance data can be converted into PpIX-weighted exposure dose, and to use this model to estimate appropriate times for dPDT across the U.K. and Ireland. METHODS: Spectral irradiance data were analysed to obtain a conversion model for illuminance to PpIX-weighted dose. This model was applied to historic illuminance data from nine sites to obtain PpIX-weighted dose across the U.K. and Ireland. Temperature data and an analysis of conservatory-based dPDT were also considered. RESULTS: Distribution of the expected PpIX-weighted dose across the nine locations is presented. Temperature data showed that it could be too cold for dPDT, even when there is sufficient light exposure. Conservatory-based dPDT could extend the times in the year for possible treatment. CONCLUSIONS: This proposed conversion model provides a means of using an illuminance reading to calculate the PpIX-weighted exposure dose. Dosimetry of dPDT may be carried out simply and at low cost using the presented method; however, the results presented may be used as a guide for those considering dPDT, without the need to conduct measurements themselves.

Does preliminary optimisation of an anatomically correct skull-brain model using simple simulants produce clinically realistic ballistic injury fracture patterns?

Ballistic head injury remains a significant threat to military personnel. Studying such injuries requires a model that can be used with a military helmet. This paper describes further work on a skull-brain model using skulls made from three different polyurethane plastics and a series of skull 'fills' to simulate brain (3, 5, 7 and 10% gelatine by mass and PermaGel™). The models were subjected to ballistic impact from 7.62 × 39 mm mild steel core bullets. The first part of the work compares the different polyurethanes (mean bullet muzzle velocity of 708 m/s), and the second part compares the different fills (mean bullet muzzle velocity of 680 m/s). The impact events were filmed using high speed cameras. The resulting fracture patterns in the skulls were reviewed and scored by five clinicians experienced in assessing penetrating head injury. In over half of the models, one or more assessors felt aspects of the fracture pattern were close to real injury. Limitations of the model include the skull being manufactured in two parts and the lack of a realistic skin layer. Further work is ongoing to address these.

Primary blast lung injury - a review.

Bomb or explosion-blast injuries are likely to be increasingly encountered as terrorist activity increases and pre-hospital medical care improves. We therefore reviewed the epidemiology, pathophysiology and treatment of primary blast lung injury. In addition to contemporary military publications and expert recommendation, an EMBASE and MEDLINE search of English speaking journals was undertaken using the medical subject headings (MeSHs) 'blast injury' and 'lung injury'. Review articles, retrospective case series, and controlled animal modelling studies published since 2000 were evaluated. 6-11% of military casualties in recent conflicts have suffered primary blast lung injury but the incidence increases to more than 90% in terrorist attacks occurring in enclosed spaces such as trains. The majority of victims require mechanical ventilation and intensive care management. Specific therapies do not exist and treatment is supportive utilizing current best practice. Understanding the consequences and supportive therapies available to treat primary blast lung injury are important for anaesthetists.

Laboratory evaluation of a novel anaesthesia delivery device.

Here, we describe proof of concept of a novel method for delivering volatile anaesthetics, where the liquid anaesthetic (sevoflurane or isoflurane) is formulated into an emulsion that is contained in a compact, lightweight device through which carrier gas flows. Release of anaesthetic is achieved by stirring of the formulation, allowing controlled and responsive release of anaesthetic at a variety of fixed flow rates between 0.5 l.min-1 and 5 l.min-1 , with ventilated, non-ventilated and draw-over breathing systems. Anaesthetic release was evaluated using target anaesthetic concentrations ranging from 0.5% v/v to 8% v/v to mimic those typically required for induction and maintenance of anaesthesia, and lower concentrations suitable for sedation. Under all conditions, output could be maintained within 0.1% v/v of the intended setting, and the device could deliver a controlled level of anaesthetic for at least 60 min, with compensation for different ambient temperatures (10-30 °C) and carrier gas flow rates. This device offers a simple, inexpensive method of delivering safe concentrations of volatile anaesthetics for a wide range of applications.

AAGBI: Safer pre-hospital anaesthesia 2017: Association of Anaesthetists of Great Britain and Ireland.

Pre-hospital emergency anaesthesia with oral tracheal intubation is the technique of choice for trauma patients who cannot maintain their airway or achieve adequate ventilation. It should be carried out as soon as safely possible, and performed to the same standards as in-hospital emergency anaesthesia. It should only be conducted within organisations with comprehensive clinical governance arrangements. Techniques should be straightforward, reproducible, as simple as possible and supported by the use of checklists. Monitoring and equipment should meet in-hospital anaesthesia standards. Practitioners need to be competent in the provision of in-hospital emergency anaesthesia and have supervised pre-hospital experience before carrying out pre-hospital emergency anaesthesia. Training programmes allowing the safe delivery of pre-hospital emergency anaesthesia by non-physicians do not currently exist in the UK. Where pre-hospital emergency anaesthesia skills are not available, oxygenation and ventilation should be maintained with the use of second-generation supraglottic airways in patients without airway reflexes, or basic airway manoeuvres and basic airway adjuncts in patients with intact airway reflexes.

A 'mixed reality' simulator concept for future Medical Emergency Response Team training.

The UK Defence Medical Service's Pre-Hospital Emergency Care (PHEC) capability includes rapid-deployment Medical Emergency Response Teams (MERTs) comprising tri-service trauma consultants, paramedics and specialised nurses, all of whom are qualified to administer emergency care under extreme conditions to improve the survival prospects of combat casualties. The pre-deployment training of MERT personnel is designed to foster individual knowledge, skills and abilities in PHEC and in small team performance and cohesion in 'mission-specific' contexts. Until now, the provision of airborne pre-deployment MERT training had been dependent on either the availability of an operational aircraft (eg, the CH-47 Chinook helicopter) or access to one of only two ground-based facsimiles of the Chinook's rear cargo/passenger cabin. Although MERT training has high priority, there will always be competition with other military taskings for access to helicopter assets (and for other platforms in other branches of the Armed Forces). This paper describes the development of an inexpensive, reconfigurable and transportable MERT training concept based on 'mixed reality' technologies-in effect the 'blending' of real-world objects of training relevance with virtual reality reconstructions of operational contexts.

Modelling primary blast lung injury: current capability and future direction.

Primary blast lung injury frequently complicates military conflict and terrorist attacks on civilian populations. The fact that it occurs in areas of conflict or unpredictable mass casualty events makes clinical study in human casualties implausible. Research in this field is therefore reliant on the use of some form of biological or non-biological surrogate model. This article briefly reviews the modelling work undertaken in this field until now and describes the rationale behind the generation of an in silico physiological model.

Imaging for Quality Control: Comparison of Systematic Video Recording to the Operative Note in Colorectal Cancer Surgery. A Pilot Study.

BACKGROUND: Oncological and functional results after colorectal cancer surgery vary considerably between hospitals and surgeons. At present, the only source of technical information about the surgical procedure is the operative note, which is subjective and omits critical information. This study aimed to evaluate the feasibility of operative video recording in demonstrating both objective information concerning the surgical procedure and surgical quality, as using a systematic approach might improve surgical performance. METHODS: From July 2015 through November 2015, patients aged ≥18 years undergoing elective colorectal cancer surgery were prospectively included in a single-institution trial. Video recording of key moments was performed peroperatively and analyzed for adequacy. The study cases were compared with a historic cohort. Video was compared with the operative note using the amount of adequate steps and a scoring system. RESULTS: This study compared 15 cases to 32 cases from the historic control group. Compared to the written operative note alone, significant differences in availability of information were seen in favor of video as well as using a combination of video plus the operative note (N adequate steps p = .024; p = <.001. Adequacy score: p = .039; p = <.001, both respectively). CONCLUSIONS: Systematic video registration is feasible and seems to improve the availability of essential information after colorectal cancer surgery. In this respect, combining video with a traditional operative note would be the best option. A multicenter international study is being organized to further evaluate the effect of operative video capture on surgical outcomes.

Died of wounds: a mortality review.

OBJECTIVES: Combat casualty care is a complex system involving multiple clinicians, medical interventions and casualty transfers. Improving the performance of this system requires examination of potential weaknesses. This study reviewed the cause and timing of death of casualties deemed to have died from their injuries after arriving at a medical treatment facility during the recent conflicts in Iraq and Afghanistan, in order to identify potential areas for improving outcomes. METHODS: This was a retrospective review of all casualties who reached medical treatment facilities alive, but subsequently died from injuries sustained during combat operations in Afghanistan and Iraq. It included all deaths from start to completion of combat operations. The UK military joint theatre trauma registry was used to identify cases, and further data were collected from clinical notes, postmortem records and coroner's reports. RESULTS: There were 71 combat-related fatalities who survived to a medical treatment facility; 17 (24%) in Iraq and 54 (76%) in Afghanistan. Thirty eight (54%) died within the first 24 h. Thirty-three (47%) casualties died from isolated head injuries, a further 13 (18%) had unsurvivable head injuries but not in isolation. Haemorrhage following severe lower limb trauma, often in conjunction with abdominal and pelvic injuries, was the cause of a further 15 (21%) deaths. CONCLUSIONS: Severe head injury was the most common cause of death. Irrespective of available medical treatment, none of this group had salvageable injuries. Future emphasis should be placed in preventative strategies to protect the head against battlefield trauma.

Primary blast lung injury at a NATO Role 3 hospital.

BACKGROUND: Primary blast lung injury (PBLI) is defined as lung contusion from barotrauma following an explosive mechanism of injury (MOI). Military data have focused on PBLI characteristics following evacuation from the combat theatre; less is known about its immediate management and epidemiology in the deployed setting. We conducted a quality improvement project to describe the prevalence, clinical characteristics, management strategies and evacuation techniques for PBLI patients prior to evacuation. METHODS: Patients admitted to a Role 3 hospital in southwest, Afghanistan, from January 2008 to March 2013 with a blast MOI were identified through the Department of Defense Trauma Registry; International Classification of Diseases 9 codes and patient record review were used to identify the PBLI cohort from radiology reports. Descriptive statistics and Fishers exact test were used to report findings. RESULTS: Prevalence of PBLI among blast injured patients with radiology reports was 11.2% (73/648). The population exhibited high Injury Severity Scores median 25 (IQR 14-34) and most received a massive blood transfusion (mean 33.4±38.3 total blood products/24 h). The mean positive end expiratory pressure (PEEP) requirement was 6.2±3.7 (range 5-15) cm H2O and PaO2 to FiO2 ratio was 297±175.2 (66-796) mm Hg. However, 16.6% of patients had a PaO2 to FiO2 ratio <200, 13.3% required PEEP ≥10 cm H2O and one patient required specialised evacuation for respiratory failure. A dismounted MOI (72.8%) and evacuation from point of injury by the Medical Emergency Response Team (62.3%) appeared to be associated with worse lung injury. Only eight of the 73 PBLI patients died and of the five with retrievable records, none died from respiratory failure. CONCLUSIONS: PBLI has a low prevalence and conventional lung protective ventilator management is generally appropriate immediately after injury; application of advanced modes of ventilation and specialised evacuation assistance may be required. PBLI may be a marker of underlying injury severity since all deaths were not due to respiratory failure. Further work is needed to determine exact MOI in mounted and dismounted casualties.

Modelling the blast environment and relating this to clinical injury: experience from the 7/7 inquest.

This paper addresses the computational modelling of a series of specific blast-related incidents and the relationships of clinical and engineering interpretations. The Royal Centre for Defence Medicine and the Defence Science and Technology Laboratory were tasked in 2010 by the UK Ministry of Defence to assist the Coroner's inquests into the 7 July 2005 London bombings. A three phase approach was taken. The first phase included an engineering expert in blast effects on structures reviewing photographs of the damaged carriages and bus to give a view on the likely physical effects on people close to the explosions. The second phase was a clinical review of the evidence by military clinicians to assess blast injury in the casualties. The third phase was to model the blast environment by structural dynamics experts to assess likely blast loading on victims to evaluate the potential blast loading on individuals. This loading information was then assessed by physiology experts. Once all teams (engineering, clinical and modelling/physiological) had separately arrived at their conclusions, the information streams were integrated to arrive at a consensus. The aim of this paper is to describe the methodology used as a potential model for others to consider if faced with a similar investigation, and to show the benefit of the transition of military knowledge to a civilian environment.

Haemorrhage and coagulopathy in the Defence Medical Services.

Over the past 12 years, the United Kingdom Defence Medical Services have evolved an integrated 'damage control resuscitation - damage control surgery' sequence for the management of patients sustaining complex injuries. During 2009, over 3200 units of blood products were administered as massive transfusions to severely injured UK personnel. An important part of the approach to traumatic bleeding is the early, empirical use of predefined ratios of blood and clotting products. As soon as control of bleeding is achieved, current practice is to switch towards a tailored transfusion, based on clinical and laboratory assessments, including point-of-care coagulation testing. A key goal is to provide resuscitation seamlessly throughout surgery, so that patients leave the operating room with their normal physiology restored. This article outlines the current management of haemorrhage and coagulation employed in Afghanistan from the point of wounding to transfer back to the National Health Service.