The combat casualty care special edition.

Corresponding Author: Colonel TJ Hodgetts QHP Honorary Professor of Emergency Medicine Academic Department of Military Emergency Medicine Institute of Research and Development, Vincent Drive, Birmingham B15 2SQ T: +44 121 415 8848 E: [email protected] ABC, DCR, DCS, RSI, MERT, MERT-Enhanced, 1:1, IRT, JTTR these contemporary abbreviations are increasingly used in conversations regarding current operational capability, are argued about passionately, and are frequently misunderstood. As an example, take the debate on how and where to perform surgery. Surgery is best performed by trained people operating within their capabilities on a patient in as good a physiological condition as possible, with the right resources, working in a safe, comfortable environment (this can be summarised as; right patient, right place, right surgeon, right time). Forward surgical facilities may allow rapid access to surgery but as these facilities are required to be manoeuvrable, they are inevitably more limited in resources compared to larger fixed facilities. Rapid evacuation from the point of wounding to a more capable, well resourced, fixed facility could be preferable but this might also lead to delays in the initial treatment of critically injured patients if the tactical situation prevented timely evacuation or the transfer time (or distance) from battlefront to the larger, more static, facility was excessive. While much can be achieved even when constraints are imposed on available resources, there comes a time when the situation falls below the minimum standard necessary to allow safe and effective surgery. This is well argued by Coupland [1] when describing high mortality rates in casualties with abdominal injury in Kabul, 1992 due to inadequate resuscitation and a lack of post operative supervision. This was a situation where large numbers of casualties presented to a hospital with a disrupted infrastructure. Lessons from the paper include the role of fluids and antibiotics in extending the timeline to definitive treatment for most patients and the need for realistic triage so that resources are not wasted on people who are going to die irrespective of whatever intervention is undertaken (this includes those with injuries outside the scope of current medical practice). Understanding who will and will not survive may appear straightforward: a casualty who has been decapitated dies instantly at the scene. A casualty with a sprained ankle should survive; but if they are isolated in mountainous or desert terrain they may perish from the effects of cold, heat and dehydration. Equally, if they are bleeding from a limb (potentially survivable) but the tactical situation prevents care reaching them (a minefield or an ongoing fire-fight) then they may die from a treatable injury. When comparing outcomes from different datasets, it is imperative that the definitions of survivability or salvagability are clearly stated and are comparable. Similarly when examining other surrogate markers of surgical performance such as amputation rates and limb salvage rates, there must be explicitly stated definitions of what is being reported (for example. amputation rate being: the number of amputated limbs / number of limb injuries; or number of amputated limbs / number of attempted limb salvage operations; or number amputated limbs / number of battle casualties etc). It is time to be moving towards accepted international consensus definitions of such terms that can be accepted within military surgical practice to allow standardised comparisons. Studying the trauma populations generated by our own forces [2-4] and others [5-9] is one part of learning where the lines between survival and non-survival are drawn and what influences these, including, of course clinical interventions. The current Battlefield Advanced Trauma Life Support (BATLS), [10] course is constructed around this concept. Simple interventions done well and close to the point of wounding aim to buy time to move a casualty through the system to the next level of care. Planning a deployed military medical service uses the estimate process and includes who is at risk, from what, and when and how this risk can be mitigated [11,12]. The plan has to consider logistic constraints imposed by the military situation. Returning to surgery, if we can accept that a certain combination of people, equipment and resources is needed then the military imperative is to make this capability as physically light and small as possible to facilitate manoeuvrability without compromising the surgical capability or standards of care. This inevitability impinges on the argument about facilities being ‘fixed’ when operating or when holding the critically ill (until evacuated) but if a ‘laboratory’ capability can be reduced to a hand-held near-patient blood analyzer (i-STAT® machine) and a portable box developed to maintain the cold chain for packed red cells and thawed plasma (the Golden Hour Container®,) then there are logistic attractions. Conversely, there are also obvious limitations of capacity and capability, but this is part of the commander’s balanced risk assessment. This must be based on tactical considerations but informed by the clinical consequences. With new approaches to resuscitation, the classically accepted timelines to surgery may now be no longer be relevant. With forward deployment of blood products it may be that these timelines can be extended with obvious implications for the optimal deployment of surgical resources. One ‘line of risk’ can be drawn between ‘resuscitation’ and ‘surgery’. Although this is a simplistic distinction (as surgery is part of resuscitation and vice versa), it does allow consideration of concepts. Internal debate has centred on whether components of resuscitation can be separated from surgery while still being effective in maintaining clinical performance standards for overall survival and morbidity. The options are to place a light, groundbased medical treatment facility in support of forward operations (that has a smaller logistic footprint than resuscitation and surgery combined) or to utilise support helicopters (SH) for primary retrieval direct to the hospital (R2E or R3) from point of wounding. Eastridge et al [13] describe the American view of INTRODUCTION