Best Evidence Topic report: Antithrombotic therapy and endovascular intervention for blunt cerebrovascular injury.

A short cut review of the literature was carried out to examine the evidence supporting antithrombotic treatment and/or endovascular therapy to reduce mortality and/or prevent future stroke following blunt cerebrovascular injury (BCVI). Five papers were identified as suitable for inclusion using the reported search strategy. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of the best papers are tabulated. It is concluded that in patients with BCVI confirmed by CT angiography, there is limited evidence to support screening for, or treating BCVI. In confirmed BCVI where the risk of stroke is felt to outweigh the risk of bleeding, antiplatelet therapy appears to be as effective as therapeutic anticoagulation.

Triage in major incidents: development and external validation of novel machine learning-derived primary and secondary triage tools.

BACKGROUND: Major incidents (MIs) are an important cause of death and disability. Triage tools are crucial to identifying priority 1 (P1) patients-those needing time-critical, life-saving interventions. Existing expert opinion-derived tools have limited evidence supporting their use. This study employs machine learning (ML) to develop and validate models for novel primary and secondary triage tools. METHODS: Adults (16+ years) from the UK Trauma Audit and Research Network (TARN) registry (January 2008-December 2017) served as surrogates for MI victims, with P1 patients identified using predefined criteria. The TARN database was split chronologically into model training and testing (70:30) datasets. Input variables included physiological parameters, age, mechanism and anatomical location of injury. Random forest, extreme gradient boosted tree, logistic regression and decision tree models were trained to predict P1 status, and compared with existing tools (Battlefield Casualty Drills (BCD) Triage Sieve, CareFlight, Modified Physiological Triage Tool, MPTT-24, MSTART, National Ambulance Resilience Unit Triage Sieve and RAMP). Primary and secondary candidate models were selected; the latter was externally validated on patients from the UK military's Joint Theatre Trauma Registry (JTTR). RESULTS: Models were internally tested in 57 979 TARN patients. The best existing tool was the BCD Triage Sieve (sensitivity 68.2%, area under the receiver operating curve (AUC) 0.688). Inability to breathe spontaneously, presence of chest injury and mental status were most predictive of P1 status. A decision tree model including these three variables exhibited the best test characteristics (sensitivity 73.0%, AUC 0.782), forming the candidate primary tool. The proposed secondary tool (sensitivity 77.9%, AUC 0.817), applicable via a portable device, includes a fourth variable (injury mechanism). This performed favourably on external validation (sensitivity of 97.6%, AUC 0.778) in 5956 JTTR patients. CONCLUSION: Novel triage tools developed using ML outperform existing tools in a nationally representative trauma population. The proposed primary tool requires external validation prior to consideration for practical use. The secondary tool demonstrates good external validity and may be used to support decision-making by healthcare workers responding to MIs.

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.

Refreshing the emergency medicine research priorities.

BACKGROUND: The priorities for UK emergency medicine research were defined in 2017 by a priority setting partnership coordinated by the Royal College of Emergency Medicine in collaboration with the James Lind Alliance (JLA). Much has changed in the last 5 years, not least a global infectious disease pandemic and a significant worsening of the crisis in the urgent and emergency care system. Our aim was to review and refresh the emergency medicine research priorities. METHODS: A steering group including patients, carers and healthcare professionals was established to agree to the methodology of the refresh. An independent adviser from the JLA chaired the steering group. The scope was adult patients in the ED. New questions were invited via an open call using multiple communications methods ensuring that patients, carers and healthcare professionals had the opportunity to contribute. Questions underwent minisystematic (BestBETs) review to determine if the question had been answered, and the original 2017 priorities were reviewed. Any questions that remained unanswered were included in an interim prioritisation survey, which was distributed to patients, carers and healthcare professionals. Rankings from this survey were reviewed by the steering group and a shortlist of questions put forward to the final workshop, which was held to discuss and rank the research questions in order of priority. RESULTS: 77 new questions were submitted, of which 58 underwent mini-systematic review. After this process, 49 questions (of which 32 were new, 11 were related to original priorities and 6 unanswered original priorities were carried forward) were reviewed by the steering group and included in an interim prioritisation survey. The interim prioritisation survey attracted 276 individual responses. 26 questions were shortlisted for discussion at the final prioritisation workshop, where the top 10 research priorities were agreed. CONCLUSION: We have redefined the priorities for emergency medicine research in the UK using robust and established methodology, which will inform the agenda for the coming years.

Association between major trauma centre care and outcomes of adult patients injured by low falls in England and Wales.

BACKGROUND: Disability and death due to low falls is increasing worldwide and disproportionately affects older adults. Current trauma systems were not designed to suit the needs of these patients. This study assessed the association between major trauma centre (MTC) care and outcomes in adult patients injured by low falls. METHODS: Data were obtained from the Trauma Audit and Research Network on adult patients injured by falls from <2 m between 2017 and 2019 in England and Wales. 30-day survival, length of hospital stay and discharge destination were compared between MTCs and trauma units or local emergency hospitals (TU/LEHs) using an adjusted multiple logistic regression model. RESULTS: 127 334 patients were included, of whom 27.6% attended an MTC. The median age was 79.4 years (IQR 64.5-87.2 years), and 74.2% of patients were aged >65 years. MTC care was not associated with improved 30-day survival (adjusted OR (AOR) 0.91, 95% CI 0.87 to 0.96, p<0.001). Transferred patients had a significant impact on the results. After excluding transferred patients, MTC care was associated with greater odds of 30-day survival (AOR 1.056, 95% CI 1.001 to 1.113, p=0.044). MTC care was also associated with greater odds of 30-day survival in the most severely injured patients (AOR 1.126, 95% CI 1.04 to 1.22, p=0.002), but not in patients aged >65 years (AOR 1.038, 95% CI 0.982 to 1.097, p=0.184). CONCLUSION: MTC care was not associated with improved survival compared with TU/LEH care in the whole cohort. Patients who were transferred had a significant impact on the results. In patients who are not transferred, MTC care is associated with greater odds of 30-day survival in the whole cohort and in the most severely injured patients. Future research must determine the optimum means of identifying patients in need of higher-level care, the components of care which improve patient outcomes, develop patient-focused outcomes which reflect the characteristics and priorities of contemporary trauma patients, and investigate the need for transfer in specific subgroups of patients.

Risk factors and outcomes of unrecognised endobronchial intubation in major trauma patients.

BACKGROUND: Emergency tracheal intubation during major trauma resuscitation may be associated with unrecognised endobronchial intubation. The risk factors and outcomes associated with this issue have not previously been fully defined. METHODS: We retrospectively analysed adult patients admitted directly from the scene to the ED of a single level 1 trauma centre, who received either prehospital or ED tracheal intubation prior to initial whole-body CT from January 2008 to December 2019. Our objectives were to describe tube-to-carina distances (TCDs) via CT and to assess the risk factors and outcomes (mortality, length of intensive care unit stay and mechanical ventilation) of patients with endobronchial intubation (TCD <0 cm) using a multivariable model. RESULTS: We included 616 patients and discovered 26 (4.2%) cases of endobronchial intubation identified on CT. Factors associated with an increased risk of endobronchial intubations were short body height (OR per 1 cm increase 0.89; 95% CI 0.84 to 0.94; p≤0.001), a high body mass index (OR 1.14; 95% CI 1.04 to 1.25; p=0.005) and ED intubation (OR 3.62; 95% CI 1.39 to 8.90; p=0.006). Eight of 26 cases underwent tube thoracostomy, four of whom had no evidence of underlying chest injury on CT. There was no statistically significant difference in mortality or length of stay although the absolute number of endobronchial intubations was small. CONCLUSIONS: Short body height and high body mass index were associated with endobronchial intubation. Before considering tube thoracostomy in intubated major trauma patients suspected of pneumothorax, the possibility of unrecognised endobronchial intubation should be considered.

Keeping it simple: the value of mortality prediction after trauma with basic indices like the Reverse Shock Index multiplied by Glasgow Coma Scale.

BACKGROUND: Identification of trauma patients at significant risk of death in the prehospital setting is challenging. The prediction probability of basic indices like vital signs, Shock Index (SI), SI multiplied by age (SIA) or the GCS is limited and more complex scores are not feasible on-scene. The Reverse SI multiplied by GCS score (rSIG) has been proposed as a triage tool to identify trauma patients with an increased risk of dying at EDs. Age adjustment (rSIG/A) displayed no advantage.We aim to (1) validate the accuracy of the rSIG in predicting death or early transfusion in a large trauma registry population, and (2) determine if the rSIG is valid for evaluation of trauma patients in the prehospital setting. METHODS: 70 829 trauma patients were retrieved from the TraumaRegister DGU database (time period between 2008 and 2017). The area under the receiver operating characteristic curve (AUROC) was calculated to measure the ability of SI, SIA, rSIG and rSIG divided by age (rSIG/A) to predict in-hospital mortality from data at the time of hospital arrival and solely from prehospital data. RESULTS: The rSIG at time of hospital admission was not sufficiently predictive for clinical decision-making. However, rSIG calculated solely from prehospital data accurately predicted risk of death. Using prehospital data, the AUROC for mortality of rSIG/A was the highest (0.85; CI: 0.85 to 0.86), followed by rSIG (0.76; CI: 0.75 to 0.77), SIA (0.71; CI: 0.70 to 0.71) and SI (0.48; CI: 0.47 to 0.49). CONCLUSION: The prehospital rSIG/A can be a useful adjunct for the prehospital evaluation of trauma patients and their allocation to trauma centres or trauma team activation. However, we could not confirm that the rSIG at hospital admission is a reliable tool for risk stratification.

Association between anticoagulants and mortality and functional outcomes in older patients with major trauma.

BACKGROUND: The number of trauma patients taking anticoagulants and antiplatelet agents is increasing as society ages. However, there have been limited and inconsistent reports of the association between anticoagulants and mortality and functional outcomes. This study aimed to quantify the association between anticoagulant/antiplatelet medication at the time of injury and both short-term and longer-term outcomes in older major trauma patients. METHODS: This was a population-based registry study using data from the Victorian State Trauma Registry from July 2017 to June 2018. We included patients with major trauma aged 65 years and older. The outcomes of interest were in-hospital mortality, hospital length of stay, intensive care unit length of stay and the Extended Glasgow Outcome Scale (GOS-E) at 6 months after injury. We examined the association between the outcomes and anticoagulants/antiplatelet agents at the time of injury and used multivariable logistic regression models to account for known confounders. RESULTS: There were 1323 older adults eligible for inclusion in the study, of which 249 (18.8%) were taking anticoagulants (n=8 were taking both anticoagulants and antiplatelet agents), 380 (28.7%) were taking antiplatelet agents and 694 (52.5%) were not using either. Any anticoagulant use was associated with higher odds of in-hospital mortality (adjusted OR (AOR), 2.38; 95% CI 1.58 to 3.59) compared with not using anticoagulants. No differences were observed in the GOS-E at 6 months after injury between any anticoagulants use, antiplatelet use and no anticoagulant use (anticoagulant AOR, 0.71; 95% CI 0.48 to 1.05, antiplatelet AOR, 1.02; 95% CI 0.73 to 1.42). CONCLUSION: Anticoagulant use at the time of injury was associated with higher odds of in-hospital mortality but did not adversely impact functional outcomes at 6 months after injury. These findings demonstrate the importance of seeking an accurate history of anticoagulant use and its indication, as well as the immediate initiation of reversal therapies.

UK healthcare staff experiences and perceptions of a mass casualty terrorist incident response: a mixed-methods study.

INTRODUCTION: System learning from major incidents is a crucial element of improving preparedness for response to any future incidents. Sharing good practice and limitations stimulates further actions to improve preparedness and prevents duplicating mistakes. METHODS: This convergent parallel mixed methods study comprises data from responses to an online survey and individual interviews with healthcare staff who took part in the responses to three terrorist incidents in the UK in 2017 (Westminster Bridge attack, Manchester Arena Bombing and London Bridge attack) to understand limitations in the response and share good practices. RESULTS: The dedication of NHS staff, staff availability and effective team work were the most frequently mentioned enabling factors in the response. Effective coordination between teams and a functional major incident plan facilitated an effective response. Rapid access to blood products, by positioning the blood bank in the ED, treating children and parents together and sharing resources between trauma centres were recognised as very effective innovative practices. Recent health emergency preparedness exercises (HEPEs) were valued for preparing both Trusts and individual staff for the response. Challenges included communication between ambulance services and hospitals, difficulties with patient identification and tracking and managing the return to 'normal' work patterns post event. Lack of immediately available clinical protocols to deal with blast injuries was the most commonly mentioned clinical issue. The need for psychosocial support for responding and supporting staff was identified. DISCUSSION: Between-agencies communication and information sharing appear as the most common recurring problems in mass casualty incidents (MCIs). Recent HEPEs, which allowed teams, interdisciplinary groups, and different agencies to practice responding to similar simulated incidents, were important and informed actions during the real response. Immediate and delayed psychosocial support should be in place for healthcare staff responding to MCIs.

Healthcare system impacts of the 2017 Manchester Arena bombing: evidence from a national trauma registry patient case series and hospital performance data.

INTRODUCTION: In response to detonation of an improvised explosive device at the Manchester Arena on 22 May 2017, we aimed to use detailed information about injured patients flowing through hospital healthcare to objectively evaluate the preplanned responses of a regional trauma care system and to show how routinely collected hospital performance data can be used to assess impact on regional healthcare. METHODS: Data about injury severity, management and outcome for patients presenting to hospitals were collated using England's major trauma registry for 30 days following hospital attendance. System-wide data about hospital performance were collated by National Health Service England's North West Utilisation Management Unit and presented as Shewhart charts from 15 April 2017 to 25 June 2017. RESULTS: Detailed information was obtained on 153 patients (109 adults and 44 children) who attended hospital emergency departments after the incident. Within 6 hours, a network of 11 regional trauma care hospitals received a total of 138 patients (90%). For the whole patient cohort, median Injury Severity Score (ISS) was 1 (IQR 1-10) and median New ISS (NISS) was 2 (IQR 1-14). For the 75 patients (49%) attending a major trauma centre, median ISS was 7.5 (IQR 1-14) and NISS was 10 (IQR 3-22). Limb and torso body regions predominated when injuries were classified as major life threatening (Abbreviated Injury Scale>3). Ninety-three patients (61%) required hospital admission following emergency department management, with 21 (14%) requiring emergency damage control surgery and 24 (16%) requiring critical care. Three fatalities occurred during early resuscitative treatment and 150 (98%) survived to day 30. The increased system-wide hospital admissions and care activity was linked to increases in regional hospital care capacity through cancellations of elective surgery and increased community care. Consequently, there were sustained system-wide hospital service improvements over the following weeks. CONCLUSIONS: The systematic collation of injured patient and healthcare system data has provided an objective evaluation of a regional major incident plan and provided insight into healthcare system resilience. Hospital patient care data indicated that a prerehearsed patient dispersal plan at incident scene was implemented effectively.

Implementation of the 'TAKE STOCK' Hot Debrief Tool in the ED: a quality improvement project.

Hot debriefing (HoD) describes a structured team-based discussion which may be initiated following a significant event. Benefits may include improved teamwork, staff well-being and identification of learning opportunities. Existing literature indicates that while staff value HoD following significant events, it is infrequently undertaken in practice. Internationally, several frameworks for HoD have been developed, although none are widely adopted for use in the ED. A quality improvement project was conducted to introduce HoD into a single UK ED in North West England, between January and March 2019. Following stakeholder consultation, the 9-item 'TAKE STOCK' tool was developed. Implementation of the tool increased the number of HoD (0-2.2 HoD episodes/week). Findings from the first plan-do-study-act (PDSA) cycle are presented, which revealed the key strengths and limitations of this model. Staff perceptions of the tool were evaluated using a self-administered short questionnaire designed by the authors. Satisfaction with TAKE STOCK was assessed using 10-point numerical scales. Across respondents (n-15), average satisfaction scores exceeded 9 out of 10 concerning patient care, staff self-care, decision-making, education, teamwork and identification of equipment issues. Implementation of HoD into the ED is feasible and viewed as beneficial by staff. Implementation toolkits for TAKE STOCK have been requested by 42 additional UK hospitals and ambulance trusts, demonstrating significant interest in its use. Research is now required to formally validate HoD frameworks for use in the ED, and assess whether HoD results in sustained improvements to staff and patient outcomes.

High incidence of surgical site infection may be related to suboptimal case selection for non-selective arterial embolization during resuscitation of patients with pelvic fractures: a retrospective study.

BACKGROUND: In most institutions, arterial embolization (AE) remains a standard procedure to achieve hemostasis during the resuscitation of patients with pelvic fractures. However, the actual benefits of AE are controversial. In this study, we aimed to explore AE-related outcomes following resuscitation at our center and to assess the predictive value of contrast extravasation (CE) during computed tomography (CT) for patients with hemodynamically unstable closed pelvic fractures. METHODS: We retrospectively reviewed data from patients who were treated for closed pelvic fractures at a single center between 2014 and 2017. Data regarding the AE and clinical parameters were analyzed to determine whether poor outcomes could be predicted. RESULTS: During the study period, 545 patients were treated for closed pelvic fractures, including 131 patients who underwent angiography and 129 patients who underwent AE. Nonselective bilateral internal iliac artery embolization (nBIIAE) was the major AE strategy (74%). Relative to the non-AE group, the AE group had higher values for injury severity score, shock at hospital arrival, and unstable fracture patterns. The AE group was also more likely to require osteosynthesis and develop surgical site infections (SSIs). Fourteen patients (10.9%) experienced late complications following the AE intervention, including 3 men who had impotence at the 12-month follow-up visit and 11 patients who developed SSIs after undergoing AE and osteosynthesis (incidence of SSI: 11/75 patients, 14.7%). Nine of the 11 patients who developed SSI after AE had undergone nBIIAE. The positive predictive value of CE during CT was 29.6%, with a negative predictive value of 91.3%. Relative to patients with identifiable CE, patients without identifiable CE during CT had a higher mortality rate (30.0% vs. 11.0%, p = 0.03). CONCLUSION: Performing AE for pelvic fracture-related hemorrhage may not be best practice for patients with no CE detected during CT or for unstable patients who do not respond to resuscitation after exclusion of other sources of hemorrhage. Given the high incidence of SSI following nBIIAE, this procedure should be selected with care. Given their high mortality rate, patients without CE during imaging might be considered for other hemostasis procedures, such as preperitoneal pelvic packing.

Biological mechanisms and individual variation in fibrinolysis after major trauma.

OBJECTIVE: To understand more about the individual variation in the time course of fibrinolysis following major injury and to assess the potential for stratification of trauma patients for tranexamic acid (TXA) therapy. METHODS: A historical dataset (from 2004) was used, consisting of samples from 52 injured patients attended by a medical prehospital system. Blood samples were taken at the incident scene, on arrival in the emergency department, 2.5 hours after hospital arrival and 5 hours after hospital arrival. From the study database, we extracted values for tissue-type plasminogen activator (tPA; an activator of fibrinolysis), one of the plasminogen activator inhibitors (PAI-1; as a natural inhibitor of fibrinolysis) and D-dimer (as a marker of the extent of fibrinolysis). RESULTS: The changes over time in median tPA and PAI-1 were mirror images, with initial high tPA levels which then rapidly decreased and low initial PAI-1 levels which slowly increased. There were high levels of fibrinolytic activity (D-dimer) throughout. This pattern was present in patients across a broad range of injury severities. CONCLUSIONS: After major trauma, there seems to be an early 'antifibrinolytic gap' with the natural antifibrinolytic system lagging several hours behind the natural profibrinolytics. An early dose of exogenous antifibrinolytic (TXA) might have its effect by filling this gap. The finding that tPA and subsequent clot breakdown (illustrated by D-dimer formation) are raised in a broad range of patients, with little correlation between the initial fibrinolytic response and markers of injury severity, may be the reason that TXA is effective across a broad range of injured patients.

Relationship between the Injury Severity Score and the need for life-saving interventions in trauma patients in the UK.

INTRODUCTION: Major trauma is the third leading cause of avoidable mortality in the UK. Defining which patients require care in a major trauma centre is a critical component of developing, evaluating and enhancing regional major trauma systems. Traditionally, trauma patients have been classified using the Injury Severity Score (ISS), but resource-based criteria have been proposed as an alternative. The aim of this study was to investigate the relationship between ISS and the use of life-saving interventions (LSI). METHODS: Retrospective cohort study using the Trauma Audit Research Network database for all adult patients (aged ≥18 years) between 2006 and 2014. Patients were categorised as needing an LSI if they received one or more interventions from a previously defined list determined by expert consensus. RESULTS: 193 290 patients met study inclusion criteria: 56.9% male, median age 60.0 years (IQR 41.2-78.8) and median ISS 9 (IQR 9-16). The most common mechanism of injury was falls <2 m (52.1%), followed by road traffic collisions (22.2%). 15.1% received one or more LSIs. The probability of a receiving an LSI increased with increasing ISS, but only a low to moderate correlation was evident (0.334, p<0.001). A clinically significant number of cases (5.3% and 7.6%) received an LSI despite having an ISS ≤8 or <15, respectively. CONCLUSIONS: A clinically significant number of adult trauma patients requiring LSIs have an ISS below the traditional definition of major trauma. The traditional definition should be reconsidered and either lowered, or an alternative metric should be used.

Implementation of tranexamic acid for bleeding trauma patients: a longitudinal and cross-sectional study.

OBJECTIVE: To describe the use of tranexamic acid (TXA) in trauma care in England and Wales since the Clinical Randomization of an Antifibrinolytic in Significant Hemorrhage (CRASH-2) trial results were published in 2010. METHODS: A national longitudinal and cross-sectional study using data collected through the Trauma Audit and Research Network (TARN), the clinical audit of major trauma care for England and Wales. All patients in the TARN database injured in England and Wales were included apart from those with an isolated traumatic brain injury, with a primary outcome of the proportion of patients given TXA and the secondary outcome of time to treatment. RESULTS: Among 228 250 patients, the proportion of trauma patients treated with TXA increased from near zero in 2010 to 10% (4593) in 2016. In 2016, most patients (82%) who received TXA did so within 3 hours of injury, however, only 30% of patients received TXA within an hour of injury. Most (80%) of the patients who had an early blood transfusion were given TXA. Patients treated with TXA by an ambulance paramedic received treatment at a median of 49 min (IQR 33-72) compared with 111 min (IQR 77-162) for patients treated in hospital. CONCLUSIONS: There is a low proportion of patients treated with TXA across the range of injury severity and the range of physiological indicators of severity of bleeding. Most patients receive treatment within the existing target of 3 hours from injury, however there remains the potential to further improve major trauma outcomes by the earlier treatment of a wider patient group.

Should we resuscitate elderly patients with blunt traumatic cardiac arrest? Analysis of National Trauma Registry Data in Japan.

OBJECTIVES: Recent studies suggest that survival after traumatic cardiac arrest (TCA) has been improving. Many elderly adults enjoy active lifestyles, which occasionally result in TCA. The epidemiology and efficacy of resuscitative procedures on blunt TCA in elderly patients are largely unknown. Our primary aim was to compare the survival to discharge following blunt TCA between non-elderly adult (ages 18-59 years) and elderly patients (age ≥60 years). METHODS: We analysed 2004-2015 observational cohort data from a nationwide trauma registry in Japan. We included all adult patients (18 years and older) who experienced blunt TCA. We excluded patients missing data for age, survival, mechanism of injury or initial vital signs. Resuscitative procedures included thoracotomy and resuscitative endovascular balloon occlusion of the aorta. We compared survival for elderly patients (age ≥60 years old) to younger adults. RESULTS: Of 8347 patients with blunt TCA, 3547 (42.5%) were elderly. Survival differed significantly by age: 164/4800 (3.4%) of younger adults survived whereas 188/3547 (5.3%) of elderly patients survived (p<0.001). Survival increased but Injury Severity Scores (ISSs) declined with increasing patient age. The efficacy of resuscitative procedures did not vary by age. In logistic regression models, increasing age was independently associated with better survival. CONCLUSION: In a cohort of patients with blunt TCA, survival increased with increasing patient age. A number of patients with low ISS in the elderly group raises the possibility that this improved survival is due to preceding or concomitant medical cardiac arrest in the older cohort. Clinicians should be cautious about applying TCA algorithms to elderly patients and should not be discouraged from resuscitating TCA because of patient age.

Pulmonary embolism following complex trauma: UK MTC observational study.

OBJECTIVES: To describe the incidence of pulmonary embolism (PE) in a critically ill UK major trauma centre (MTC) patient cohort. METHODS: A retrospective, multidataset descriptive study of all trauma patients requiring admission to level 2 or 3 care in the East of England MTC from 1 November 2014 to 1 May 2017. Data describing demographics, the nature and extent of injuries, process of care, timing of PE prophylaxis, tranexamic acid (TXA) administration and CT scanner type were extracted from the Trauma Audit and Research Network database and hospital electronic records. PE presentation was categorised as immediate (diagnosed on initial trauma scan), early (within 72 hours of admission but not present initially) and late (diagnosed after 72 hours). RESULTS: Of the 2746 trauma patients, 1039 were identified as being admitted to level 2 or 3 care. Forty-eight patients (4.6%) were diagnosed with PE during admission with 14 immediate PEs (1.3%). Of 32.1% patients given TXA, 6.3% developed PE compared with 3.8% without TXA (p=0.08). CONCLUSION: This is the largest study of the incidence of PE in UK MTC patients and describes the greatest number of immediate PEs in a civilian complex trauma population to date. Immediate PEs are a rare phenomenon whose clinical importance remains unclear. Tranexamic acid was not significantly associated with an increase in PE in this population following its introduction into the UK trauma care system.

Prehospital determinants of successful resuscitation after traumatic and non-traumatic out-of-hospital cardiac arrest.

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is prevalent in the UK. Reported survival is lower than in countries with comparable healthcare systems; a better understanding of outcome determinants may identify areas for improvement. METHODS: An analysis of 9109 OHCA attended in East of England between 1 January 2015 and 31 July 2017. Univariate descriptives and multivariable analysis were used to understand the determinants of survival for non-traumatic cardiac arrest (NTCA) and traumatic cardiac arrest (TCA). Two Utstein outcome variables were used: survival to hospital admission and hospital discharge. RESULTS: The incidence of OHCA was 55.1 per 100 000 population/year. The overall survival to hospital admission was 27.6% (95% CI 26.7% to 28.6%) and the overall survival to discharge was 7.9% (95% CI 7.3% to 8.5%). Survival to hospital admission and survival to hospital discharge were both greater in the NTCA group compared with the TCA group: 27.9% vs 19.3% p=0.001, and 8.0% vs 3.8% p=0.012 respectively.Determinants of NTCA and TCA survival were different, and varied according to the outcome examined. In NTCA, bystander cardiopulmonary resuscitation (CPR) was associated with survival at discharge but not at admission, and the likelihood of bystander CPR was dependent on geographical socioeconomic status. An air ambulance was associated with increased survival to both hospital admission and discharge in NTCA, but only with survival to admission in TCA. CONCLUSION: NTCA and TCA are clinically distinct entities with different predictors for outcome-future OHCA reports should aim to separate arrest aetiologies. Determinants of survival to hospital admission and discharge differ in a way that likely reflects the determinants of neurological injury. Bystander CPR public engagement may be best focused in more deprived areas.

Issues and challenges for research in major trauma.

The starting point for evidence-based guidelines is the systematic review and critical appraisal of the relevant literature. This review highlights the risk of bias identified while critically appraising the evidence to inform the National Institute of Health and Care Excellence guideline on the assessment and initial management of major trauma.