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Vascular injury is a leading cause of death and disability in military and civilian settings. Most wartime and an increasing amount of civilian vascular trauma arises from penetrating mechanisms of injury due to gunshot or explosion. The objective of this study was to provide a comprehensive examination of penetrating lower extremity arterial injury and to characterize long-term limb salvage and differences related to mechanisms of injury.The military trauma registries of the United States and the United Kingdom were analyzed to identify service members who sustained penetrating lower limb arterial injury (2001-2014). Treatment and limb salvage data were studied and comparisons made of patients whose penetrating vascular trauma arose from explosion (group 1) vs gunshot (group 2). Standardized statistical testing was used, with Bonferroni corrections for multiple comparisons.The cohort consisted of 568 combat casualties (mean age, 25.2 years) with 597 injuries (explosion, n = 416; gunshot, n = 181). Group 1 had higher Injury Severity Score (P .05) and Mangled Extremity Severity Score (P .0001), required more blood transfusion (P .05), and had more tibial (P .01) and popliteal (P .05) arterial injuries; group 2 had more profunda femoris injuries (P .05). Initial surgical management for the whole cohort included vein interposition graft (33%), ligation (31%), primary repair with or without patch angioplasty (16%), temporary vascular shunting (15%), and primary amputation (6%). No difference in patency of arterial reconstruction was found between group 1 and group 2, although group 1 had a higher incidence of primary (13% vs 2%; P .05) and secondary (19% vs 9%; P .05) amputation. Similarly, longer term freedom from amputation was lower for group 1 than for group 2 (68% vs 89% at 5.5 years; Cox hazard ratio, 0.30; P .0001), as was physical functioning (36-Item Short Form Health Survey data; mean, 39.80 vs 43.20; P .05).The majority of wartime lower extremity arterial injuries result from an explosive mechanism that preferentially affects the tibial vasculature and results in poorer long-term limb salvage compared with those injured with firearms. The mortality associated with immediate limb salvage attempts is low, and delayed amputations occur weeks later, affording the patient involvement in the decision-making and rehabilitation planning. We recommend assertive attempts at vascular repair and limb salvage for service members injured by explosive and gunshot mechanisms.

Background Quality improvement (QI) programs have shown to reduce preventable mortality in trauma care. Detailed review of all trauma deaths is a time and resource consuming process and calculated probability of survival (Ps) has been proposed as audit filter. Review is limited on deaths that were ‘expected to survive’. However no Ps-based algorithm has been validated and no study has examined elements of preventability associated with deaths classified as ‘expected’. The objective of this study was to examine whether trauma performance review can be streamlined using existing mortality prediction tools without missing important areas for improvement. Methods We conducted a retrospective study of all trauma deaths reviewed by our trauma QI program. Deaths were classified into non-preventable, possibly preventable, probably preventable or preventable. Opportunities for improvement (OPIs) involve failure in the process of care and were classified into clinical and system deviations from standards of care. TRISS and PS were used for calculation of probability of survival. Peer-review charts were reviewed by a single investigator. Results Over 8 years, 626 patients were included. One third showed elements of preventability and 4% were preventable. Preventability occurred across the entire range of the calculated Ps band. Limiting review to unexpected deaths would have missed over 50% of all preventability issues and a third of preventable deaths. 37% of patients showed opportunities for improvement (OPIs). Neither TRISS nor PS allowed for reliable identification of OPIs and limiting peer-review to patients with unexpected deaths would have missed close to 60% of all issues in care. Conclusions TRISS and PS fail to identify a significant proportion of avoidable deaths and miss important opportunities for process and system improvement. Based on this, all trauma deaths should be subjected to expert panel review in order to aim at a maximal output of performance improvement programs.

Display Omitted We focus on complex clinical problems where data is available in small amounts.Our methodology compensates for the lack of data by using published evidence.It combines multivariate data with univariate meta-analysis to build BN models.The method is illustrated by a medical case study on trauma care.Our method outperformed data-driven techniques and MESS model in the case study. Complex clinical decisions require the decision maker to evaluate multiple factors that may interact with each other. Many clinical studies, however, report 'univariate' relations between a single factor and outcome. Such univariate statistics are often insufficient to provide useful support for complex clinical decisions even when they are pooled using meta-analysis. More useful decision support could be provided by evidence-based models that take the interaction between factors into account. In this paper, we propose a method of integrating the univariate results of a meta-analysis with a clinical dataset and expert knowledge to construct multivariate Bayesian network (BN) models. The technique reduces the size of the dataset needed to learn the parameters of a model of a given complexity. Supplementing the data with the meta-analysis results avoids the need to either simplify the model - ignoring some complexities of the problem - or to gather more data. The method is illustrated by a clinical case study into the prediction of the viability of severely injured lower extremities. The case study illustrates the advantages of integrating combined evidence into BN development: the BN developed using our method outperformed four different data-driven structure learning methods, and a well-known scoring model (MESS) in this domain.

Graphical abstractDisplay Omitted We focus on latent clinical factors that can only be indirectly observed.We propose a methodology of developing BNs that reason with latent variables.A series of expert reviews reveal the relation between data and latent variables.The method is illustrated by a medical case study on trauma care.The case study displays significant predictive improvements from the expert reviews. Many medical conditions are only indirectly observed through symptoms and tests. Developing predictive models for such conditions is challenging since they can be thought of as 'latent' variables. They are not present in the data and often get confused with measurements. As a result, building a model that fits data well is not the same as making a prediction that is useful for decision makers. In this paper, we present a methodology for developing Bayesian network (BN) models that predict and reason with latent variables, using a combination of expert knowledge and available data. The method is illustrated by a case study into the prediction of acute traumatic coagulopathy (ATC), a disorder of blood clotting that significantly increases the risk of death following traumatic injuries. There are several measurements for ATC and previous models have predicted one of these measurements instead of the state of ATC itself. Our case study illustrates the advantages of models that distinguish between an underlying latent condition and its measurements, and of a continuing dialogue between the modeller and the domain experts as the model is developed using knowledge as well as data.

ObjectivesIn the United Kingdom, the epidemiology, management strategies and outcomes from vascular trauma are unknown. The aim of this study was to describe the vascular trauma experience of a British Trauma Centre.MethodsA retrospective observational study of all patients admitted to hospital with traumatic vascular injury between 2005 and 2010.ResultsVascular injuries were present in 256 patients (4.4%) of the 5823 total trauma admissions. Penetrating trauma caused 135 (53%) vascular injuries whilst the remainder resulted from blunt trauma. Compared to penetrating vascular trauma, patients with blunt trauma were more severely injured (median ISS 29 [18–38] vs. ISS 11 [9–17], p

Objective This retrospective study aimed to explore the role of Glasgow Aneurysm Score (GAS) and Hardman Index (HI) in predicting outcome after elective endovascular aneurysm repair (EVAR). Methods All 71 patients who underwent elective EVAR in a single centre over 9 years were reviewed. Clinical data were used to classify patients into the three standard GAS tertiles and to score patients according to the HI. Results Fifty-one patients scored ≥ 77 according to GAS. Actual and predicted mortality in this group were 3.9% and 9.3%. Seventeen patients scored between 69 and 77 with actual and predicted mortality of 0% and 4.1%. Three patients scored less than 69 with actual and predicted mortality of 0% and 2.4%. Ten patients scored ≥ 3 on the HI with actual and predicted mortality of 10% and 100%, respectively. Twenty-four patients scored 2 with actual and predicted mortality of 4.2% and 55%. Twenty-seven patients scored 1 with actual and predicted mortality of 0% and 28%, respectively. Ten patients scored 0 with actual and predicted mortality of 0% and 16%, respectively. The χ 2 test showed extremely significant p value of 0.0001 in case of HI, and p value of 0.0800 for GAS, slightly less significant, probably due to the small sample size. Conclusion Contrary to their role in ruptured and open aortic aneurysm repair, GAS and HI overestimate both mortality and morbidity following EVAR and are poor predictors of outcome.

Objective Graduated compression stockings are a valuable means of thrombo-prophylaxis but it is unclear whether knee-length (KL) or thigh length (TL) stockings are more effective. The aim of this review was to systematically analyse randomised controlled trials that have evaluated stocking length and efficacy of thromboprophylaxis. Method A systematic review of the literature was undertaken. Clinical trials on hospitalised populations and passengers on long haul flights were selected according to specific criteria and analysed to generate summated data. Results 14 randomized control trials were analysed. Thirty six of 1568 (2.3%) participants randomised to KL stockings developed a deep venous thrombosis, compared with 79 of 1696 (5%) in the TL control/thigh length group. Substantial heterogeneity was observed amongst trials. KL stockings had a significant effect to reduce the incidence of DVT in long haul flight passengers, odds ration 0.08 (95%CI 0.03–0.22). In hospitalised patients KL stockings did not appear to be far worse than TL stockings, odds ratio 1.01 (95%CI 0.35–2.90). For combined passengers and patients, there was a benefit in favour of KL stockings, weighted odds ratio 0.45 (95% CI 0.30–0.68). Conclusion KL graduated stockings can be as effective as TL stockings for the prevention of DVT, whilst offering advantages in terms of patient compliance and cost.

Background Junctional vascular trauma such as that at the thoracic outlet poses particular challenges in surgical management. The use of endovascular techniques for such injuries is attractive as repair may be facilitated without the need for thoracotomy; however, the utility of such techniques is currently based on opinion, small retrospective series, and literature reviews of narrative and not systematic quality. The objective of this study is to provide a complete and systematic analysis of the literature pertaining to open surgery (OS) and endovascular management (EM) of thoracic outlet vascular injuries. Methods An electronic search using the MEDLINE, Embase, Cochrane Library, Science Citation Index, and LILACS databases was performed for articles published from 1947 to November 2011. The review conformed to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement standards. Prospective studies and retrospective cohorts of more than 10 patients were included. The primary outcome was all-cause mortality. Results One prospective noncomparative study and 73 retrospective series met the inclusion criteria. There were no randomized studies. All studies were at high risk of bias. Fifteen studies described outcomes for both OS and EM (549 patients). The majority of these studies described EM for traumatic arteriovenous fistulas or false aneurysms in stable patients. Direct comparison between OS and EM was possible in only three studies (comprising 23 OS and 25 EM patients), which showed no difference in all-cause mortality (odds ratio, 0.67; 95% confidence interval [CI], 0.11-4.05), but a shorter operating time with EM (mean difference = 58.34 minutes; 95% CI, 17.82-98.85). These three series included successful EM of unstable patients and those with vessel transection. There were 55 studies describing only OS (2057 patients) with a pooled mortality rate of 12.4% (95% CI, 9.9%-15.2%). Four studies described only EM (101 patients) with a pooled mortality rate of 26% (95% CI, 8%-51%), but these represented a distinct subgroup of cases (mainly iatrogenic injuries in older patients). Conclusions The current evidence is weak and fails to show superiority of one modality over the other. EM is currently used primarily in highly selected cases, but there are reports of a broader applicability in trauma. High-quality randomized studies or large-scale registry data are needed to further comment on the relative merits or disadvantages of EM in comparison to OS.

Introduction: Vascular injuries are complex, challenging, time-critical and have a high mortality. We undertook this study to identify the incidence, mechanism and vessels involved in fatal vascular injuries at a UK urban trauma centre. Method: Retrospective review of all patients with vascular injuries over a 47-month period from July 2003 to May 2007. Results: A total of 3164 patients were admitted following a trauma call over the study period, 104 of which sustained vascular injuries (3.3%). The median (i.q. range) ISS for those with vascular injuries was 20 (10-34) whereas for all trauma patients it was 9 (1-16). Penetrating trauma comprised 46% vascular injuries (n = 48) of which 5 were gunshot wounds. Motor vehicle collisions were the cause for 40 of the 56 blunt vascular injuries. Among the patients with vascular injuries there were 20 deaths (19%), 7 penetrating trauma (all stab wounds) and 13 blunt trauma (7 motor vehicle collisions, 2 falls from height, 2 crushed by heavy objects, 1 blast injury, 1 hit by train). Conclusion: Vascular injuries are uncommon but carry a significant mortality. Death is usually associated with torso haemorrhage including junctional zones. The non-compressible nature of these injuries means that extremely rapid transportation and intervention are essential if mortality is to be reduced.

Aim: A core function of established trauma systems is to improve performance through peer identification and review of potentially preventable mortality. The aim of this study was to evaluate the rate and cause of excess mortality occurring in an inner-city trauma centre that has invested substantial resources in developing a dedicated trauma service. Method: Retrospective peer review of all in-hospital deaths from April 2003-April 2004. Three external international trauma authorities graded each death as not preventable, possibly preventable, probably preventable or preventable according to the American College of Surgeons guidelines. Mortalities were then assigned a preventability score of 1-4 accordingly, with an aggregate score of =7 flagged as potentially preventable. Results: One hundred and seventy seven patients with an ISS greater than 15 were admitted, of whom 32 (18%) died. Twenty-nine patients who died from burn (n = 1), penetrating (n = 4) or blunt injury (n = 25) had retrievable post-mortem reports and were referred for peer review. The median (range) ISS and TRISS scores were 29 (17-75) and 36 (0-97). Median (range) preventability score was 4 (3-7). Mean weighted Kappa co-efficient for inter-observer variability was 0.345, indicating fair agreement between panel members. No death was considered entirely preventable. Five (17%) cases were assigned as potentially preventable. The principle variances from standard of care identified in these cases included delay to surgery/angio for haemorrhage control (4 cases), and delay in evacuating intracranial haematoma (1). Other variances identified in non-preventable deaths were failure to apply damage control principles during surgery and avoidable secondary brain injury (2). Conclusion: Delay to theatre or failure to utilise damage control principles was the primary cause of potentially avoidable death in major trauma patients. Robust, peer review systems assist objective analysis and the development of a culture of safety and quality, and are essential if excess trauma mortality is to be minimised.