Evaluating patient factors, operative management and postoperative outcomes in trauma laparotomy patients worldwide: a protocol for a global observational multicentre trauma study.

INTRODUCTION: Trauma contributes to the greatest loss of disability-adjusted life-years for adolescents and young adults worldwide. In the context of global abdominal trauma, the trauma laparotomy is the most commonly performed operation. Variation likely exists in how these patients are managed and their subsequent outcomes, yet very little global data on the topic currently exists. The objective of the GOAL-Trauma study is to evaluate both patient and injury factors for those undergoing trauma laparotomy, their clinical management and postoperative outcomes. METHODS: We describe a planned prospective multicentre observational cohort study of patients undergoing trauma laparotomy. We will include patients of all ages who present to hospital with a blunt or penetrating injury and undergo a trauma laparotomy within 5 days of presentation to the treating centre. The study will collect system, patient, process and outcome data, following patients up until 30 days postoperatively (or until discharge or death, whichever is first). Our sample size calculation suggests we will need to recruit 552 patients from approximately 150 recruiting centres. DISCUSSION: The GOAL-Trauma study will provide a global snapshot of the current management and outcomes for patients undergoing a trauma laparotomy. It will also provide insight into the variation seen in the time delays for receiving care, the disease and patient factors present, and patient outcomes. For current standards of trauma care to be improved worldwide, a greater understanding of the current state of trauma laparotomy care is paramount if appropriate interventions and targets are to be identified and implemented.

Prevalence of chronic pain after severe lower limb injury (SLLI): A systematic review and meta-analysis.

BACKGROUND: Globally, severe lower limb injuries (SLLIs) are the predominant cause of long-term injury related disability and poor functional outcomes. Chronic pain is a major source of this morbidity, but the magnitude of the contribution is not clearly understood. The aim of this systematic review and meta-analysis was to determine the prevalence of chronic pain following SLLIs in civilian and military patients. METHOD: This systematic review was prospectively registered with The International Prospective Register of Systematic Reviews (PROSPERO) with study ID CRD42022313615. A systematic literature search (Medline, Embase, Ovid, and Web of Science) was performed to identify original studies that reported chronic pain outcomes for adults who underwent surgical treatment for SLLIs in a civilian or military setting. Risk of bias in included studies was assessed using the ROBINS-E tool, and quality assessment was reported at study level using the Newcastle-Ottawa Scale, and at outcome-level using the GRADE framework. Absolute (proportional) and relative (odds ratio) outcome measures were calculated and pooled using a random effects model. RESULTS: Forty-three studies reporting the outcomes of 5601 patients were included. Estimated overall prevalence of pain was 63 % (CI 55-70 %). The prevalence of chronic pain in amputees (64 % (CI 55-73 %)) was similar to those who underwent limb salvage (56 % (CI 44-67 %)). The prevalence of chronic pain in civilian populations was 70 % (CI 63-77 %) compared to military populations (51 % (CI 35-66 %)). In amputees, the prevalence of residual limb pain was similar to phantom limb pain (OR 1.06 [0.64-1.78], p = 0.81, I2 = 92 %). CONCLUSION: Most people who sustain a SLLI will suffer from chronic pain. Healthcare systems must continue to research interventions that can reduce the incidence and severity of long-term pain and ensure adequate resources are allocated for this common and debilitating complication.

Identification of major hemorrhage in trauma patients in the prehospital setting: diagnostic accuracy and impact on outcome.

Background: Hemorrhage is the most common cause of potentially preventable death after injury. Early identification of patients with major hemorrhage (MH) is important as treatments are time-critical. However, diagnosis can be difficult, even for expert clinicians. This study aimed to determine how accurate clinicians are at identifying patients with MH in the prehospital setting. A second aim was to analyze factors associated with missed and overdiagnosis of MH, and the impact on mortality. Methods: Retrospective evaluation of consecutive adult (≥16 years) patients injured in 2019-2020, assessed by expert trauma clinicians in a mature prehospital trauma system, and admitted to a major trauma center (MTC). Clinicians decided to activate the major hemorrhage protocol (MHPA) or not. This decision was compared with whether patients had MH in hospital, defined as the critical admission threshold (CAT+): administration of ≥3 U of red blood cells during any 60-minute period within 24 hours of injury. Multivariate logistical regression analyses were used to analyze factors associated with diagnostic accuracy and mortality. Results: Of the 947 patients included in this study, 138 (14.6%) had MH. MH was correctly diagnosed in 97 of 138 patients (sensitivity 70%) and correctly excluded in 764 of 809 patients (specificity 94%). Factors associated with missed diagnosis were penetrating mechanism (OR 2.4, 95% CI 1.2 to 4.7) and major abdominal injury (OR 4.0; 95% CI 1.7 to 8.7). Factors associated with overdiagnosis were hypotension (OR 0.99; 95% CI 0.98 to 0.99), polytrauma (OR 1.3, 95% CI 1.1 to 1.6), and diagnostic uncertainty (OR 3.7, 95% CI 1.8 to 7.3). When MH was missed in the prehospital setting, the risk of mortality increased threefold, despite being admitted to an MTC. Conclusion: Clinical assessment has only a moderate ability to identify MH in the prehospital setting. A missed diagnosis of MH increased the odds of mortality threefold. Understanding the limitations of clinical assessment and developing solutions to aid identification of MH are warranted. Level of evidence: Level III-Retrospective study with up to two negative criteria. Study type: Original research; diagnostic accuracy study.

Updating and recalibrating causal probabilistic models on a new target population.

OBJECTIVE: Very often the performance of a Bayesian Network (BN) is affected when applied to a new target population. This is mainly because of differences in population characteristics. External validation of the model performance on different populations is a standard approach to test model's generalisability. However, a good predictive performance is not enough to show that the model represents the unique population characteristics and can be adopted in the new environment. METHODS: In this paper, we present a methodology for updating and recalibrating developed BN models - both their structure and parameters - to better account for the characteristics of the target population. Attention has been given on incorporating expert knowledge and recalibrating latent variables, which are usually omitted from data-driven models. RESULTS: The method is successfully applied to a clinical case study about the prediction of trauma-induced coagulopathy, where a BN has already been developed for civilian trauma patients and now it is recalibrated on combat casualties. CONCLUSION: The methodology proposed in this study is important for developing credible models that can demonstrate a good predictive performance when applied to a target population. Another advantage of the proposed methodology is that it is not limited to data-driven techniques and shows how expert knowledge can also be used when updating and recalibrating the model.

Current knowledge and availability of machine learning across the spectrum of trauma science.

PURPOSE OF REVIEW: Recent technological advances have accelerated the use of Machine Learning in trauma science. This review provides an overview on the available evidence for research and patient care. The review aims to familiarize clinicians with this rapidly evolving field, offer perspectives, and identify existing and future challenges. RECENT FINDINGS: The available evidence predominantly focuses on retrospective algorithm construction to predict outcomes. Few studies have explored actionable outcomes, workflow integration, or the impact on patient care. Machine Learning and data science have the potential to simplify data capture and enhance counterfactual causal inference research from observational data to address complex issues. However, regulatory, legal, and ethical challenges associated with the use of Machine Learning in trauma care deserve particular attention. SUMMARY: Machine Learning holds promise for actionable decision support in trauma science, but rigorous proof-of-concept studies are urgently needed. Future research should assess workflow integration, human-machine interaction, and, most importantly, the impact on patient outcome. Machine Learning enhanced causal inference for observational data carries an enormous potential to change trauma research as complement to randomized studies. The scientific trauma community needs to engage with the existing challenges to drive progress in the field.

Nationwide analysis of prehospital tranexamic acid for trauma demonstrates systematic bias in adherence to treatment guidelines: a retrospective cohort study.

BACKGROUND: Prehospital (PH) tranexamic acid (TXA) improves survival from trauma haemorrhage. Injury mechanism, physiology, and sex demographics vary with patient age. The authors hypothesised that these factors influence TXA guideline compliance and examined national trends in PH use to identify any systematic biases in bleeding management. MATERIALS AND METHODS: The UK Trauma Audit and Research Network data for TXA eligible patients admitted to major trauma centres were divided into two cohorts: 2013-2015 ( n =32 072) and 2017-2019 ( n =14 974). Patients were stratified by PH, emergency department or no TXA use. Logistic regression models explored interaction between PH variables and TXA administration. Results are presented as odds ratios with a 95% CI. RESULTS: PH TXA use increased from 8% to 27% over time ( P <0.001). Only 3% of eligible patients who fell less than 2 m received PH TXA versus 63% with penetrating injuries ( P <0.001). Older patients eligible for PH TXA were less likely to receive it compared to younger patients [≥65 years old: 590 (13%) vs. <65 years old: 3361 (33%), P <0.001]. There was a significant interaction between age and sex with fewer older women receiving PH TXA. In shocked patients, one third of females compared to a fifth of men did not receive TXA ( P <0.001). There was a decrease in PH TXA use as age increased ( P <0.001). CONCLUSIONS: Despite a threefold increase in use, treatment guidance for PH TXA is not universally applied. Older people, women, and patients with low energy injury mechanisms appear to be systematically under treated. Training and education for PH providers should address these potential treatment biases.

Understanding pre-hospital blood transfusion decision-making for injured patients: an interview study.

BACKGROUND: Blood transfusion for bleeding trauma patients is a promising pre-hospital intervention with potential to improve outcomes. However, it is not yet clear which patients may benefit from pre-hospital transfusions. The aim of this study was to enhance our understanding of how experienced pre-hospital clinicians make decisions regarding patient blood loss and the need for transfusion, and explore the factors that influence clinical decision-making. METHODS: Pre-hospital physicians, from two air ambulance sites in the south of England, were interviewed between December 2018 and January 2019. Participants were involved in teaching or publishing on the management of bleeding trauma patients and had at least 5 years of continuous and contemporary practice at consultant level. Interviews were semi-structured and explored how decisions were made and what made decisions difficult. A qualitative description approach was used with inductive thematic analysis to identify themes and subthemes related to blood transfusion decision-making in trauma. RESULTS: Ten pre-hospital physicians were interviewed and three themes were identified: recognition-primed analysis, uncertainty and imperfect decision analysis. The first theme describes how participants make decisions using selected cues, incorporating their experience and are influenced by external rules and group expectations. What made decisions difficult for the participants was encapsulated in the uncertainty theme. Uncertainty emerged regarding the patient's true underlying physiological state and the treatment effect of blood transfusion. The last theme focuses on the issues with decision-making itself. Participants demonstrated lapses in decision awareness, often incomplete decision evaluation and described challenges to effective learning due to incomplete patient outcome information. CONCLUSION: Pre-hospital clinicians make decisions about bleeding and transfusion which are recognition-primed and incorporate significant uncertainty. Decisions are influenced by experience and are subject to bias. Improved understanding of the decision-making processes provides a theoretical perspective of how decisions might be supported in the future.

Methods used to evaluate usability of mobile clinical decision support systems for healthcare emergencies: a systematic review and qualitative synthesis.

Objective: The aim of this study was to determine the methods and metrics used to evaluate the usability of mobile application Clinical Decision Support Systems (CDSSs) used in healthcare emergencies. Secondary aims were to describe the characteristics and usability of evaluated CDSSs. Materials and Methods: A systematic literature review was conducted using Pubmed/Medline, Embase, Scopus, and IEEE Xplore databases. Quantitative data were descriptively analyzed, and qualitative data were described and synthesized using inductive thematic analysis. Results: Twenty-three studies were included in the analysis. The usability metrics most frequently evaluated were efficiency and usefulness, followed by user errors, satisfaction, learnability, effectiveness, and memorability. Methods used to assess usability included questionnaires in 20 (87%) studies, user trials in 17 (74%), interviews in 6 (26%), and heuristic evaluations in 3 (13%). Most CDSS inputs consisted of manual input (18, 78%) rather than automatic input (2, 9%). Most CDSS outputs comprised a recommendation (18, 78%), with a minority advising a specific treatment (6, 26%), or a score, risk level or likelihood of diagnosis (6, 26%). Interviews and heuristic evaluations identified more usability-related barriers and facilitators to adoption than did questionnaires and user testing studies. Discussion: A wide range of metrics and methods are used to evaluate the usability of mobile CDSS in medical emergencies. Input of information into CDSS was predominantly manual, impeding usability. Studies employing both qualitative and quantitative methods to evaluate usability yielded more thorough results. Conclusion: When planning CDSS projects, developers should consider multiple methods to comprehensively evaluate usability.

Diagnostic accuracy of clinical examination to identify life- and limb-threatening injuries in trauma patients.

BACKGROUND: Timely and accurate identification of life- and limb-threatening injuries (LLTIs) is a fundamental objective of trauma care that directly informs triage and treatment decisions. However, the diagnostic accuracy of clinical examination to detect LLTIs is largely unknown, due to the risk of contamination from in-hospital diagnostics in existing studies. Our aim was to assess the diagnostic accuracy of initial clinical examination for detecting life- and limb-threatening injuries (LLTIs). Secondary aims were to identify factors associated with missed injury and overdiagnosis, and determine the impact of clinician uncertainty on diagnostic accuracy. METHODS: Retrospective diagnostic accuracy study of consecutive adult (≥ 16 years) patients examined at the scene of injury by experienced trauma clinicians, and admitted to a Major Trauma Center between 01/01/2019 and 31/12/2020. Diagnoses of LLTIs made on contemporaneous clinical records were compared to hospital coded diagnoses. Diagnostic performance measures were calculated overall, and based on clinician uncertainty. Multivariate logistic regression analyses identified factors affecting missed injury and overdiagnosis. RESULTS: Among 947 trauma patients, 821 were male (86.7%), median age was 31 years (range 16-89), 569 suffered blunt mechanisms (60.1%), and 522 (55.1%) sustained LLTIs. Overall, clinical examination had a moderate ability to detect LLTIs, which varied by body region: head (sensitivity 69.7%, positive predictive value (PPV) 59.1%), chest (sensitivity 58.7%, PPV 53.3%), abdomen (sensitivity 51.9%, PPV 30.7%), pelvis (sensitivity 23.5%, PPV 50.0%), and long bone fracture (sensitivity 69.9%, PPV 74.3%). Clinical examination poorly detected life-threatening thoracic (sensitivity 48.1%, PPV 13.0%) and abdominal (sensitivity 43.6%, PPV 20.0%) bleeding. Missed injury was more common in patients with polytrauma (OR 1.83, 95% CI 1.62-2.07) or shock (systolic blood pressure OR 0.993, 95% CI 0.988-0.998). Overdiagnosis was more common in shock (OR 0.991, 95% CI 0.986-0.995) or when clinicians were uncertain (OR 6.42, 95% CI 4.63-8.99). Uncertainty improved sensitivity but reduced PPV, impeding diagnostic precision. CONCLUSIONS: Clinical examination performed by experienced trauma clinicians has only a moderate ability to detect LLTIs. Clinicians must appreciate the limitations of clinical examination, and the impact of uncertainty, when making clinical decisions in trauma. This study provides impetus for diagnostic adjuncts and decision support systems in trauma.

Causes and associations with mortality in patients with pelvic ring injuries with haemorrhagic shock.

BACKGROUND: High energy pelvic ring injuries are associated with significant morbidity and mortality and can be accompanied by haemorrhagic shock following associated vascular injury. This study evaluated the causes and predictors of mortality in haemodynamically unstable pelvic fractures. METHODS: This retrospective observational study at a Major Trauma Centre reviewed 938 consecutive adult patients (≥ 18yrs) with pelvic ring injuries between December 2014 and November 2018. Patients with features of haemorrhagic shock were included, defined as: arrival Systolic BP < 90 mmHg, Base Deficit ≥ 6.0 mmol/l, or transfusion of ≥ 4 units of packed red blood cells within 24 h. RESULTS: Of the 102 patients included, all sustained injuries from high energy trauma, and 47.1% underwent a haemorrhage control intervention (Resuscitative Endovascular Balloon Occlusion of the Aorta-REBOA, Interventional Radiology-IR, or Laparotomy). These were more often required following vertical shear injuries (OR 10.7, p = 0.036). Overall, 33 patients (32.4%) died; 16 due to a head injury, and only 2 directly from acute pelvic exsanguination (6.1%). Multivariable logistic regression demonstrated that increasing age, Injury Severity Score, Abbreviated Injury Scale (AIS) Head ≥ 3 and open pelvic fracture were all independent predictors of mortality, and IR was associated with reduced mortality. Lateral Compression III (LC3) injuries were associated with mortality due to multiple organ dysfunction syndrome (MODS). CONCLUSION: Haemodynamically unstable patients with pelvic ring injuries have a high mortality rate, but death is usually attributed to other injuries or later complications, and not from acute exsanguination. This reflects improvements in resuscitative care, transfusion protocols, and haemorrhage control techniques.

Impact of Ischemia Duration on Lower Limb Salvage in Combat Casualties.

INTRODUCTION: The 6-hour threshold to revascularization of an ischemic limb is ubiquitous in the trauma literature, however, contemporary evidence suggests that this threshold should be less. This study aims to characterize the relationship between the duration of limb ischemia and successful limb salvage following lower extremity arterial trauma. METHODS: This is a cohort study of the United States and UK military service members injured while serving in Iraq or Afghanistan between 2003 and 2013. Consecutive patients who sustained iliac, femoral, or popliteal artery injuries, and underwent surgery to attempt revascularization, were included. The association between limb outcome and the duration of limb ischemia was assessed using the Kaplan-Meier method. RESULTS: One hundred twenty-two patients (129 limbs) who sustained iliac (2.3%), femoral (56.6%), and popliteal (41.1%) arterial injuries were included. Overall, 87 limbs (67.4%) were successfully salvaged. The probability of limb salvage was 86.0% when ischemia was ≤1 hour; 68.3% when between 1 and 3 hours; 56.3% when between 3 and 6 hours; and 6.7% when >6 hours ( P <0.0001). Shock more than doubled the risk of failed limb salvage [hazard ratio=2.42 (95% confidence interval: 1.27-4.62)]. CONCLUSIONS: Limb salvage is critically dependent on the duration of ischemia with a 10% reduction in the probability of successful limb salvage for every hour delay to revascularization. The presence of shock significantly worsens this relationship. Military trauma systems should prioritize rapid hemorrhage control and early limb revascularization within 1 hour of injury.

Effectiveness of intubation devices in patients with cervical spine immobilisation: a systematic review and network meta-analysis.

BACKGROUND: Cervical spine immobilisation increases the difficulty of tracheal intubation. Many intubation devices have been evaluated in this setting, but their relative performance remains uncertain. METHODS: MEDLINE, EMBASE, and the Cochrane Library were searched to identify randomised trials comparing two or more intubation devices in adults with cervical spine immobilisation. After critical appraisal, a random-effects network meta-analysis was used to pool and compare device performance. The primary outcome was the probability of first-attempt intubation success (first-pass success). For relative performance, the Macintosh direct laryngoscopy blade was chosen as the reference device. RESULTS: We included 80 trials (8039 subjects) comparing 26 devices. Compared with the Macintosh, McGrath™ (odds ratio [OR]=11.5; 95% credible interval [CrI] 3.19-46.20), C-MAC D Blade™ (OR=7.44; 95% CrI, 1.06-52.50), Airtraq™ (OR=5.43; 95% CrI, 2.15-14.2), King Vision™ (OR=4.54; 95% CrI, 1.28-16.30), and C-MAC™ (OR=4.20; 95% CrI=1.28-15.10) had a greater probability of first-pass success. This was also true for the GlideScope™ when a tube guide was used (OR=3.54; 95% CrI, 1.05-12.50). Only the Airway Scope™ had a better probability of first-pass success compared with the Macintosh when manual-in-line stabilisation (MILS) was used as the immobilisation technique (OR=7.98; 95% CrI, 1.06-73.00). CONCLUSIONS: For intubation performed with cervical immobilisation, seven devices had a better probability of first-pass success compared with the Macintosh. However, more studies using MILS (rather than a cervical collar or other alternative) are needed, which more accurately represent clinical practice. CLINICAL TRIAL REGISTRATION: PROSPERO 2019 CRD42019158067 (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=158067).

The impact of prehospital TXA on mortality among bleeding trauma patients: A systematic review and meta-analysis.

BACKGROUND: Tranexamic acid (TXA) is an antifibrinolytic drug associated with improved survival among trauma patients with hemorrhage. Tranexamic acid is considered a primary hemostatic intervention in prehospital for treatment of bleeding alongside blood product transfusion. METHODS: A systematic review and meta-analysis was conducted to investigate the impact of prehospital TXA on mortality among trauma patients with bleeding. A systematic search was conducted using the National Institute for Health and Care Excellence Healthcare Databases Advanced Search library which contain the following of databases: EMBASE, Medline, PubMed, BNI, EMCARE, and HMIC. Other databases searched included SCOPUS and the Cochrane Central Register for Clinical Trials Library. Quality assessment tools were applied among included studies; Cochrane Risk of Bias for randomized control trials and Newcastle-Ottawa Scale for cohort observational studies. RESULTS: A total of 797 publications were identified from the initial database search. After removing duplicates and applying inclusion/exclusion criteria, four studies were included in the review and meta-analysis which identified a significant survival benefit in patients who received prehospital TXA versus no TXA. Three observational cohort and one randomized control trial were included into the review with a total of 2,347 patients (TXA, 1,169 vs. no TXA, 1,178). There was a significant reduction in 24 hours mortality; odds ratio (OR) of 0.60 (95% confidence interval [CI], 0.37-0.99). No statistical significant differences in 28 days to 30 days mortality; OR of 0.69 (95% CI, 0.47-1.02), or venous thromboembolism OR of 1.49 (95% CI, 0.90-2.46) were found. CONCLUSION: This review demonstrates that prehospital TXA is associated with significant reductions in the early (24 hour) mortality of trauma patients with suspected or confirmed hemorrhage but no increase in the incidence of venous thromboembolism. LEVEL OF EVIDENCE: Systematic review and meta-analysis. Level I.

Intraosseous access in the resuscitation of trauma patients: a literature review.

PURPOSE: Intraosseous (IO) catheters continue to be recommended in trauma resuscitation. Their utility has recently been debated due to concerns regarding inadequate flow rates during blood transfusion, and the potential for haemolysis. The objective of this review was to examine the evidence for intraosseous catheters in trauma resuscitation, and to highlight areas for future research. METHODS: A PubMed and Embase search for articles published from January 1990 to August 2018 using the terms ("intra-osseous access" or "intraosseous access" or "IO access") AND trauma was performed. Original articles describing the use of an IO catheter in the resuscitation of one or more trauma patients were eligible. Animal, cadaveric studies and those involving healthy volunteers were excluded. RESULTS: Nine studies, comprising of 1218 trauma patients and 1432 device insertions, were included. The insertion success rate was 95% and the incidence of complications 0.9%. Flow-rate data and evidence of haemolysis were poorly reported. CONCLUSION: Intraosseous catheters have high insertion success rates and a low incidence of complications in trauma patients. Existing evidence suggests that IO transfusion is not associated with haemolysis, however, further studies in humans are needed. There is a paucity of flow rate data for blood transfusion via IO catheters in this population, although much anecdotal evidence advocating their use exists.

Early Identification of Trauma-induced Coagulopathy: Development and Validation of a Multivariable Risk Prediction Model.

OBJECTIVE: The aim of this study was to develop and validate a risk prediction tool for trauma-induced coagulopathy (TIC), to support early therapeutic decision-making. BACKGROUND: TIC exacerbates hemorrhage and is associated with higher morbidity and mortality. Early and aggressive treatment of TIC improves outcome. However, injured patients that develop TIC can be difficult to identify, which may compromise effective treatment. METHODS: A Bayesian Network (BN) prediction model was developed using domain knowledge of the causal mechanisms of TIC, and trained using data from 600 patients recruited into the Activation of Coagulation and Inflammation in Trauma (ACIT) study. Performance (discrimination, calibration, and accuracy) was tested using 10-fold cross-validation and externally validated on data from new patients recruited at 3 trauma centers. RESULTS: Rates of TIC in the derivation and validation cohorts were 11.8% and 11.0%, respectively. Patients who developed TIC were significantly more likely to die (54.0% vs 5.5%, P < 0.0001), require a massive blood transfusion (43.5% vs 1.1%, P < 0.0001), or require damage control surgery (55.8% vs 3.4%, P < 0.0001), than those with normal coagulation. In the development dataset, the 14-predictor BN accurately predicted this high-risk patient group: area under the receiver operating characteristic curve (AUROC) 0.93, calibration slope (CS) 0.96, brier score (BS) 0.06, and brier skill score (BSS) 0.40. The model maintained excellent performance in the validation population: AUROC 0.95, CS 1.22, BS 0.05, and BSS 0.46. CONCLUSIONS: A BN (http://www.traumamodels.com) can accurately predict the risk of TIC in an individual patient from standard admission clinical variables. This information may support early, accurate, and efficient activation of hemostatic resuscitation protocols.

Predicting the Outcome of Limb Revascularization in Patients With Lower-extremity Arterial Trauma: Development and External Validation of a Supervised Machine-learning Algorithm to Support Surgical Decisions.

OBJECTIVES: Estimating the likely success of limb revascularization in patients with lower-extremity arterial trauma is central to decisions between attempting limb salvage and amputation. However, the projected outcome is often unclear at the time these decisions need to be made, making them difficult and threatening sound judgement. The objective of this study was to develop and validate a prediction model that can quantify an individual patient's risk of failed revascularization. METHODS: A BN prognostic model was developed using domain knowledge and data from the US joint trauma system. Performance (discrimination, calibration, and accuracy) was tested using ten-fold cross validation and externally validated on data from the UK Joint Theatre Trauma Registry. BN performance was compared to the mangled extremity severity score. RESULTS: Rates of amputation performed because of nonviable limb tissue were 12.2% and 19.6% in the US joint trauma system (n = 508) and UK Joint Theatre Trauma Registry (n = 51) populations respectively. A 10-predictor BN accurately predicted failed revascularization: area under the receiver operating characteristic curve (AUROC) 0.95, calibration slope 1.96, Brier score (BS) 0.05, and Brier skill score 0.50. The model maintained excellent performance in an external validation population: AUROC 0.97, calibration slope 1.72, Brier score 0.08, Brier skill score 0.58, and had significantly better performance than mangled extremity severity score at predicting the need for amputation [AUROC 0.95 (0.92-0.98) vs 0.74 (0.67-0.80); P < 0.0001]. CONCLUSIONS: A BN (https://www.traumamodels.com) can accurately predict the outcome of limb revascularization at the time of initial wound evaluation. This information may complement clinical judgement, support rational and shared treatment decisions, and establish sensible treatment expectations.

Diagnostic performance of EUS in non-jaundiced patients with an incidental finding of double duct sign on cross-sectional imaging: A systematic review and meta-analysis.

BACKGROUND/OBJECTIVES: Dilatation of the pancreatic duct and common bile duct, known as double duct sign (DDS), suggests sinister pathology at the periampullary region. Non-jaundiced patients with incidental DDS and otherwise normal cross-sectional imaging present a diagnostic dilemma to the multidisciplinary team (MDT). The primary aim of this review was to assess the diagnostic yield of endoscopic ultrasound (EUS) in detecting causal pathology in this patient population. METHODS: A systematic literature search (Medline, EMBASE, Google Scholar, Cochrane database and PROSPERO) was performed to identify original studies that reported EUS findings in patients with incidental DDS. Primary outcome was detection of a periampullary tumour. Secondary outcome was detection of benign causal pathology. Meta-analysis was used to calculate an absolute measure (pooled proportion) of pathology detection. RESULTS: Four studies (177 patients) were included. EUS detection rate for a periampullary tumour was 5% (95% CI, 0-10%) including both adenocarcinomas and adenomas. EUS detection rate for benign causal pathology was 22% (95% CI, 10-34%), the most common being chronic pancreatitis CONCLUSION: Non-jaundiced patients with incidental DDS on cross-sectional imaging have a 5% risk of a periampullary tumour that can be detected by EUS.