Sound the Alarm: The Sonographer Shortage Is Echoing Across Healthcare.

OBJECTIVES: The growth in ultrasound usage necessitates concurrent growth in the number of sonographers. Despite the increasing importance of ultrasound, there is a shortage of sonographers in the United States that has never been specifically quantified. This study examines recent trends in the number of ultrasound exams, sonography graduates, open sonographer positions, and wages. METHODS: This retrospective study uses public databases and surveys including the Medical Expenditure Panel Survey (MEPS), Bureau of Labor Statistics (BLS), Integrated Postsecondary Education Data System (IPEDS), and Zippia, a human resources platform to determine metrics. These metrics include the number of ultrasound exams conducted in the United States (excluding inpatient setting), number of sonographers and sonographer wages, sonography graduates, and open sonographer positions. RESULTS: Ultrasound exams in the United States from 2011 to 2021 increased from 38.6 million to 59.8 million (+55.1%,) while the number of sonographers (2011-2021) increased from 54,760 to 78,640 (+43.6%). There was a significant difference between supply and demand of sonographers with the number of sonography graduates (2011-2021) increasing from 4,386 to 5,393 (+23.0%) while the number of open sonographer positions (2012-2021) increased from 18,462 to 25,162 (+36.3%). CONCLUSIONS: From 2011 to 2021, the increase in the number of ultrasound exams has significantly outpaced the increase in the number of sonographers. Furthermore, the increase in demand for sonographers has grown significantly faster than the supply, leading to a shortage and consequent strain on the healthcare system. To address the shortage, the number of sonography school openings should be increased, and the attendant challenges addressed.

Perceived barriers and opportunities to improve working conditions and staff retention in emergency departments: a qualitative study.

BACKGROUND: Staff retention in Emergency Medicine (EM) is at crisis level and could be attributed in some part to adverse working conditions. This study aimed to better understand current concerns relating to working conditions and working practices in Emergency Departments (EDs). METHODS: A qualitative approach was taken, using focus groups with ED staff (doctors, nurses, advanced care practitioners) of all grades, seniority and professional backgrounds from across the UK. Snowball recruitment was undertaken using social media and Royal College of Emergency Medicine communication channels. Focus group interviews were conducted online and organised by profession. A semi-structured topic guide was used to explore difficulties in the work environment, impact of these difficulties, barriers and priorities for change. Data were analysed using a directive content analysis to identify common themes. RESULTS: Of the 116 clinical staff who completed the eligibility and consent forms, 46 met criteria and consented, of those, 33 participants took part. Participants were predominantly white British (85%), females (73%) and doctors (61%). Four key themes were generated: 'culture of blame and negativity', 'untenable working environments', 'compromised leadership' and 'striving for support'. Data pertaining to barriers and opportunities for change were identified as sub-themes. In particular, strong leadership emerged as a key driver of change across all aspects of working practices. CONCLUSION: This study identified four key themes related to workplace concerns and their associated barriers and opportunities for change. Culture, working environment and need for support echoed current narratives across healthcare settings. Leadership emerged more prominently than in prior studies as both a barrier and opportunity for well-being and retention in the EM workplace. Further work is needed to develop leadership skills early on in clinical training, ensure protected time to deliver the role, ongoing opportunities to refine leadership skills and a clear pathway to address higher levels of management.

The RELIEF feasibility trial: topical lidocaine patches in older adults with rib fractures.

BACKGROUND: Lidocaine patches, applied over rib fractures, may reduce pulmonary complications in older patients. Known barriers to recruiting older patients in emergency settings necessitate a feasibility trial. We aimed to establish whether a definitive randomised controlled trial (RCT) evaluating lidocaine patches in older patients with rib fracture(s) was feasible. METHODS: This was a multicentre, parallel-group, open-label, feasibility RCT in seven hospitals in England and Scotland. Patients aged ≥65 years, presenting to ED with traumatic rib fracture(s) requiring hospital admission were randomised to receive up to 3×700 mg lidocaine patches (Ralvo), first applied in ED and then once daily for 72 hours in addition to standard care, or standard care alone. Feasibility outcomes were recruitment, retention and adherence. Clinical end points (pulmonary complications, pain and frailty-specific outcomes) and patient questionnaires were collected to determine feasibility of data collection and inform health economic scoping. Interviews and focus groups with trial participants and clinicians/research staff explored the understanding and acceptability of trial processes. RESULTS: Between October 23, 2021 and October 7, 2022, 206 patients were eligible, of whom 100 (median age 83 years; IQR 74-88) were randomised; 48 to lidocaine patches and 52 to standard care. Pulmonary complications at 30 days were determined in 86% of participants and 83% of expected 30-day questionnaires were returned. Pulmonary complications occurred in 48% of the lidocaine group and 59% in standard care. Pain and some frailty-specific outcomes were not feasible to collect. Staff reported challenges in patient compliance, unfamiliarity with research measures and overwhelming the patients with research procedures. CONCLUSION: Recruitment of older patients with rib fracture(s) in an emergency setting for the evaluation of lidocaine patches is feasible. Refinement of data collection, with a focus on the collection of pain, frailty-specific outcomes and intervention delivery are needed before progression to a definitive trial. TRIAL REGISTRATION NUMBER: ISRCTN14813929.

HEART Score Recalibration Using Higher Sensitivity Troponin T.

STUDY OBJECTIVE: We examined the diagnostic performance of a recalibrated History, Electrocardiogram, Age, Risk factors, Troponin (HEART), and Thrombolysis in Myocardial Infarction (TIMI) score in patients with suspected acute cardiac syndrome (ACS). Recalibration of troponin thresholds was performed, including shifting from the 99th percentile to the limit of detection (LOD) or to the limit of quantification (LOQ) We compared the discharge potential and safety of the recalibrated composite scores using a single presentation high-sensitivity cardiac troponin (hs-cTn) T to the conventional scores and with a LOD/LOQ troponin strategy alone. METHODS: We undertook a 2-center prospective cohort study in the United Kingdom (UK) (2018) (Clinicaltrials.gov NCT03619733) to specifically assess recalibrated risk scores (shifting the troponin subset scoring from 99th percentile to LOD [UK]) and combined the results of this with secondary analyses of 2 prospective cohort studies in the UK (2011) and the United States (2018, using LOQ rather than LOD). The primary outcome was major adverse cardiovascular events (MACE), defined as adjudicated type 1 myocardial infarction (MI), urgent coronary revascularization, and all-cause death, at 30 days. We evaluated the original scores using hs-cTn below the 99th percentile and recalibrated scores using hs-cTn

Diagnostic Accuracy of Clinical Pathways for Suspected Acute Myocardial Infarction in the Out-of-Hospital Environment.

STUDY OBJECTIVE: Chest pain is one of the most common reasons for emergency ambulance calls. Patients are routinely transported to the hospital to prevent acute myocardial infarction (AMI). We evaluated the diagnostic accuracy of clinical pathways in the out-of-hospital environment. The Troponin-only Manchester Acute Coronary Syndromes decision aid and History, ECG, Age, Risk Factors, Troponin score require cardiac troponin (cTn) measurement, whereas the History and ECG-only Manchester Acute Coronary Syndromes decision aid and History, ECG, Age, Risk Factors score do not. METHODS: We conducted a prospective diagnostic accuracy study at 4 ambulance services and 12 emergency departments between February 2019 and March 2020. We included patients who received an emergency ambulance response in whom paramedics suspected AMI. Paramedics recorded the data required to calculate each decision aid and took venous blood samples in the out-of-hospital environment. Samples were tested using a point-of-care cTn assay (Roche cobas h232) within 4 hours. The target condition was a diagnosis of type 1 AMI, adjudicated by 2 investigators. RESULTS: Of 817 included participants, 104 (12.8%) had AMI. Setting the cutoff at the lowest risk group, Troponin-only Manchester Acute Coronary Syndromes had 98.3% sensitivity (95% confidence interval 91.1% to 100%) and 25.5% specificity (21.4% to 29.8%) for type 1 AMI. History, ECG, Age, Risk Factors, Troponin had 86.4% sensitivity (75.0% to 98.4%) and 42.2% specificity (37.5% to 47.0%); History and ECG-only Manchester Acute Coronary Syndromes had 100% sensitivity (96.4% to 100%) and 3.1% specificity (1.9% to 4.7%), whereas History, ECG, Age, Risk Factors had 95.1% sensitivity (88.9% to 98.4%) and 12.1% specificity (9.8% to 14.8%). CONCLUSION: With point-of-care cTn testing, decision aids can identify patients at a low risk of type 1 AMI in the out-of-hospital environment. When used alongside clinical judgment, and with appropriate training, such tools may usefully enhance out-of-hospital risk stratification.

Drink and injection spiking: how to approach an increase in presentations?

In 2021, there was a significant increase in the number of reported drink spiking incidents across the UK. The new phenomenon of spiking via injection also emerged, which gained significant media attention. Campaigns encouraged potential spiking victims to attend an ED for testing. However, there is limited published research on drink spiking and no published studies on injection spiking. One UK guideline for the management of spiking exists, advising testing 'if clinically indicated' and is likely underused. Therefore, patients are often managed without drug testing, psychological support or a clear onward referral pathway. This practice review will explore the background of spiking, discuss drug testing options and highlight the psychological sequelae of spiking. An example guideline for the management of spiking incidents is attached.

Cross-cultural adaptation and its impact on research in emergency care.

The perspective of patients is increasingly recognised as important to care improvement and innovation. Patient questionnaires such as patient-reported outcome measures may often require cross-cultural adaptation (CCA) to gather their intended information most effectively when used in cultures and languages different to those in which they were developed. The use of CCA could be seen as a practical step in addressing the known problems of inclusion, diversity and access in medical research.An example of the recent adaptation of a patient-reported outcome measure for use with ED patients is used to explore some key features of CCA, introduce the importance of CCA to emergency care practitioners and highlight the limitations of CCA.

External validation of the Manchester Acute Coronary Syndromes ECG risk model within a pre-hospital setting.

OBJECTIVES: The Manchester Acute Coronary Syndromes ECG (MACS-ECG) prediction model calculates a score based on objective ECG measurements to give the probability of a non-ST elevation myocardial infarction (NSTEMI). The model showed good performance in the emergency department (ED), but its accuracy in the pre-hospital setting is unknown. We aimed to externally validate MACS-ECG in the pre-hospital environment. METHODS: We undertook a secondary analysis from the Pre-hospital Evaluation of Sensitive Troponin (PRESTO) study, a multi-centre prospective study to validate decision aids in the pre-hospital setting (26 February 2019 to 23 March 2020). Patients with chest pain where the treating paramedic suspected acute coronary syndrome were included. Paramedics collected demographic and historical data and interpreted ECGs contemporaneously (as 'normal' or 'abnormal'). After completing recruitment, we analysed ECGs to calculate the MACS-ECG score, using both a pre-defined threshold and a novel threshold that optimises sensitivity to differentiate AMI from non-AMI. This was compared with subjective ECG interpretation by paramedics. The diagnosis of AMI was adjudicated by two investigators based on serial troponin testing in hospital. RESULTS: Of 691 participants, 87 had type 1 AMI and 687 had complete data for paramedic ECG interpretation. The MACS-ECG model had a C-index of 0.68 (95% CI: 0.61 to 0.75). At the pre-determined cut-off, MACS-ECG had 2.3% (95% CI: 0.3% to 8.1%) sensitivity, 99.5% (95% CI: 98.6% to 99.9%) specificity, 40.0% (95% CI: 10.2% to 79.3%) positive predictive value (PPV) and 87.6% (87.3% to 88.0%) negative predictive value (NPV). At the optimal threshold for sensitivity, MACS-ECG had 50.6% sensitivity (39.6% to 61.5%), 83.1% specificity (79.9% to 86.0%), 30.1% PPV (24.7% to 36.2%) and 92.1% NPV (90.4% to 93.5%). In comparison, paramedics had a sensitivity of 71.3% (95% CI: 60.8% to 80.5%) with 53.8% (95% CI: 53.8% to 61.8%) specificity, 19.7% (17.2% to 22.45%) PPV and 93.3% (90.8% to 95.1%) NPV. CONCLUSION: Neither MACS-ECG nor paramedic ECG interpretation had a sufficiently high PPV or NPV to 'rule in' or 'rule out' NSTEMI alone.

Psychological predictors of health anxiety and pain in ambulatory presentations in a hospital emergency department.

BACKGROUND: Health anxiety in attendees of out-patient medical clinics is well established; however, there has been a lack of research into health anxiety within emergency settings. AIMS: This study explored the prevalence of health anxiety in ambulatory presentations in a tertiary emergency department (ED) as well as the factors associated with pain and health anxiety in this setting. METHOD: A cross-sectional questionnaire design was used to gather data from adult ED ambulatory attendees across a 4-day sampling period to assess psychological and physical health variables. Number of attendances to ED over the previous 12 months was accessed through healthcare records. RESULTS: Of the final sample (n = 106), 77% were white British, 54% were male, and 14% presented with severe health anxiety as measured by the Short Health Anxiety Inventory (≥18). Participants with pre-existing health conditions had significantly higher levels of health anxiety (M = 12.36, SE = 1.59) compared with those without (M = 7.79, SE = 0.66). Stepwise multiple regression analyses identified anxiety sensitivity and pain catastrophizing as significant independent predictors of health anxiety, explaining 51% of the variance in health anxiety. Pain catastrophizing was also a significant independent predictor of pain level, accounting for 20% of the variance. CONCLUSION: This study provides insight into the prevalence of health anxiety in ED ambulatory presentations and key psychological predictors of health anxiety and pain. This has implications for treatment in an ED setting whereby patients may benefit from referral to medical psychology or mental health services.

Current management of moderate to severe traumatic pneumothoraces: a survey of emergency clinicians.

BACKGROUND: Traumatic pneumothoraces are present in one-fifth of multiple trauma victims. Traditional teaching mandates the insertion of a chest drain in the majority of cases. However, recent observational evidence suggests a trend towards conservative management. The aim of this survey was to understand current emergency medicine (EM) practice in placing chest drains for the management of moderate to severe traumatic pneumothoraces. METHODOLOGY: The survey was developed through expert consensus and sent electronically to senior EM doctors in 21 sites internationally. It described six clinical/imaging vignettes asking 'how likely are you to insert an intercostal chest drain to manage the pneumothorax in ED?'. A five-point response was available from very unlikely to very likely. All pneumothoraces were >1 cm on imaging, but mechanism, physiology and need for ventilation varied. RESULTS: Of a potential 606 respondents, 222 responses were received (37% response rate). Respondents were from five different countries, with the majority qualified for more than 10 years (median; 18 years). Within each scenario, there was a large variation in responses with the exception of tension pneumothorax. For vignettes without tension pneumothorax, there was a range from 52% (non-compromised 1 cm pneumothorax in a ventilated patient) to 89% (open pneumothorax with minimal clinical compromise) in respondents reporting that they would be likely or very likely to insert a chest drain. CONCLUSION: There is considerable variation in clinical practice involving both conservative and invasive strategies in the treatment of moderate to severe traumatic pneumothoraces. This suggests clinical equipoise for interventional trials to determine the optimal management strategy for this patient group.

Identifying low-risk chest pain in the emergency department without troponin testing: a validation study of the HE-MACS and HEAR risk scores.

INTRODUCTION: Patients presenting to EDs with chest pain of possible cardiac origin represent a substantial and challenging cohort to risk stratify. Scores such as HE-MACS (History and Electrocardiogram-only Manchester Acute Coronary Syndromes decision aid) and HEAR (History, ECG, Age, Risk factors) have been developed to stratify risk without the need for troponin testing. Validation of these scores remains limited. METHODS: We performed a post hoc analysis of the Limit of Detection and ECG discharge strategy randomised-controlled trial dataset (n=629; June 2018 to March 2019; 8 UK hospitals) to calculate HEAR and HE-MACS scores. A <4% risk of major adverse cardiac events (MACE) at 30 days using HE-MACS and a score of <2 calculated using HEAR defined 'very low risk' patients suitable for discharge. The primary outcome of MACE at 30 days was used to assess diagnostic accuracy. RESULTS: MACE within 30 days occurred in 42/629 (7%) of the cohort. HE-MACS and HEAR scores identified 85/629 and 181/629 patients as 'very low risk', with MACE occurring in 0/85 and 1/181 patients, respectively. The sensitivities of each score for ruling out MACE were 100% (95% CI: 91.6% to 100%) for HE-MACS and 97.6% (95% CI: 87.7% to 99.9%) for HEAR. Presenting symptoms within these scores were poorly predictive, with only diaphoresis reaching statistical significance (OR: 4.99 (2.33 to 10.67)). Conventional cardiovascular risk factors and clinician suspicion were related to the presence of MACE at 30 days. CONCLUSION: HEAR and HE-MACS show potential as rule out tools for acute myocardial infarction without the need for troponin testing. However, prospective studies are required to further validate these scores.

Emergency management of older people with cervical spine injuries: an expert practice review.

Spinal fractures are the third most common traumatic injury in older people, of which cervical spine injuries make up around 15%. They are predominantly seen in people living with frailty who fall from standing height. Spinal fractures in this patient group are associated with substantial morbidity and mortality (over 40% at 1 year). For many older people who survive, their injuries will be life changing. Practice between EDs varies significantly, with no universally accepted guidelines on either assessment, investigation or management specific to older people experiencing trauma. This expert practice review examines the current evidence and emergency management options in this patient group through clinical scenarios, with the aim of providing a more unified approach to management.

Patients' and health professionals' perceptions of the LoDED (limit of detection and ECG discharge) strategy for low-risk chest pain management: a qualitative study.

BACKGROUND: Rapid discharge strategies for patients with low-risk chest pain using high-sensitivity troponin assays have been extensively evaluated. The adherence to, and acceptability of such strategies, has largely been explored using quantitative data. The aims of this integrated qualitative study were to explore the acceptability of the limit of detection and ECG discharge strategy (LoDED) to patients and health professionals, and to refine a discharge information leaflet for patients with low-risk chest pain. METHODS: Patients with low-risk chest pain who consented to a semi-structured interview were purposively sampled for maximum variation from four of the participating National Health Service sites between October 2018 and May 2019. Two focus groups with ED health professionals at two of the participating sites were completed in April and June 2019. RESULTS: A discharge strategy based on a single undetectable hs-cTn test (LoDED) was acceptable to patients. They trusted the health professionals who were treating them and felt reassured by other tests, (ECG) alongside blood test(s), even when the clinical assessment did not provide a firm diagnosis. In contrast, health professionals had reservations about the LoDED strategy, including concern about identifying low-risk patients and a shortened patient observation period. Findings from 11 patient interviews and 2 staff focus groups (with 20 clinicians) centred around three overarching themes: acceptability of the LoDED strategy, perceptions of symptom severity and uncertainty, and patient discharge information. CONCLUSION: Rapid discharge for low-risk chest pain is acceptable to patients, but clinicians reported some reticence in implementing the LoDED strategy. Further work is required to optimise discharge discussions and information provision for patients.

Diagnostic accuracy of the magnetocardiograph for patients with suspected acute coronary syndrome.

BACKGROUND: We aimed to estimate the diagnostic accuracy of the VitalScan magnetocardiograph (MCG) for suspected acute coronary syndrome (ACS). METHODS: We undertook a prospective cohort study evaluating the diagnostic accuracy of the MCG in adults with suspected ACS. The reference standard of ACS was determined by an independent adjudication committee based on 30-day investigations and events. The cohort was split into a training sample, to derive the MCG algorithm and an algorithm combining MCG with a modified Manchester Acute Coronary Syndrome (MACS) clinical probability score, and a validation sample, to estimate diagnostic accuracy. RESULTS: We recruited 756 participants and analysed data from 680 (293 training, 387 validation), of whom 96 (14%) had ACS. In the training sample, the respective area under the receiver operating characteristic (AUROC) curves were the following: MCG 0.66 (95% CI 0.58 to 0.74), MACS 0.64 (95% CI 0.54 to 0.73) and MCG+MACS 0.70 (95% CI 0.63 to 0.77). MCG specificity was 0.16 (95% CI 0.12 to 0.21) at the threshold achieving acceptable sensitivity for rule-out (>0.98). In the validation sample (n=387), the respective AUROCs were the following: MCG 0.56 (95% CI 0.48 to 0.64), MACS 0.69 (95% CI 0.61 to 0.77) and MCG+MACS 0.64 (95% CI 0.56 to 0.72). MCG sensitivity was 0.89 (95% CI 0.77 to 0.95) and specificity 0.15 (95% CI 0.12 to 0.20) at the rule-out threshold. MCG+MACS sensitivity was 0.85 (95% CI 0.73 to 0.92) and specificity 0.30 (95% CI 0.25 to 0.35). CONCLUSION: The VitalScan MCG is currently unable to accurately rule out ACS and is not yet ready for use in clinical practice. Further developmental research is required.

Psychological distress during the acceleration phase of the COVID-19 pandemic: a survey of doctors practising in emergency medicine, anaesthesia and intensive care medicine in the UK and Ireland.

OBJECTIVE: To quantify psychological distress experienced by emergency, anaesthetic and intensive care doctors during the acceleration phase of COVID-19 in the UK and Ireland. METHODS: Initial cross-sectional electronic survey distributed during acceleration phase of the first pandemic wave of COVID-19 in the UK and Ireland (UK: 18 March 2020-26 March 2020 and Ireland: 25 March 2020-2 April 2020). Surveys were distributed via established specialty research networks, within a three-part longitudinal study. Participants were doctors working in emergency, anaesthetic and intensive medicine during the first pandemic wave of COVID-19 in acute hospitals across the UK and Ireland. Primary outcome measures were the General Health Questionnaire-12 (GHQ-12). Additional questions examined personal and professional characteristics, experiences of COVID-19 to date, risk to self and others and self-reported perceptions of health and well-being. RESULTS: 5440 responses were obtained, 54.3% (n=2955) from emergency medicine and 36.9% (n=2005) from anaesthetics. All levels of doctor seniority were represented. For the primary outcome of GHQ-12 score, 44.2% (n=2405) of respondents scored >3, meeting the criteria for psychological distress. 57.3% (n=3045) had never previously provided clinical care during an infectious disease outbreak but over half of respondents felt somewhat prepared (48.6%, n=2653) or very prepared (7.6%, n=416) to provide clinical care to patients with COVID-19. However, 81.1% (n=4414) either agreed (31.1%, n=2709) or strongly agreed (31.1%, n=1705) that their personal health was at risk due to their clinical role. CONCLUSIONS: Findings indicate that during the acceleration phase of the COVID-19 pandemic, almost half of frontline doctors working in acute care reported psychological distress as measured by the GHQ-12. Findings from this study should inform strategies to optimise preparedness and explore modifiable factors associated with increased psychological distress in the short and long term. TRIAL REGISTRATION NUMBER: ISRCTN10666798.

Blunt chest trauma in the elderly: an expert practice review.

Trauma in the elderly (>65 years) is an increasingly common presentation to the ED. A fall from standing height is the most common mechanism after which such patients present, and rib fracture is the most common non-spinal fracture. Thoracic injury in patients aged over 65 is associated with significant morbidity and mortality. There are currently no universally applied guidelines for assessment, investigation and management of such patients. In this expert practice review, we discuss the evidence base and options for clinical management in this vulnerable patient group.

BET 1: Efficacy of different techniques using a metered-dose inhaler with Spacer to relieve symptoms in children with acute asthma.

A shortcut review was carried out to establish which inhaler with spacer technique provides the greatest improvement in symptoms in children with acute asthma. Four relevant papers were identified for inclusion using the reported search strategy. The author, date and country of publication; group studied; study type; relevant outcomes; results and study weaknesses of these papers are tabulated. It is concluded that a 'tidal breathing' technique, with a minimum of three breaths per inhaler activation, is likely equivalent in efficacy to a 'single breath and hold technique', and easier for a breathless child to perform.

Diagnostic Accuracy of a New High-Sensitivity Troponin I Assay and Five Accelerated Diagnostic Pathways for Ruling Out Acute Myocardial Infarction and Acute Coronary Syndrome.

STUDY OBJECTIVE: This diagnostic accuracy study describes the performance of 5 accelerated chest pain pathways, calculated with the new Beckman's Access high-sensitivity troponin I assay. METHODS: High-sensitivity troponin I was measured with presentation and 2-hour blood samples in 1,811 patients who presented to an emergency department (ED) in Australia. Patients were classified as being at low risk according to 5 rules: modified accelerated diagnostic protocol to assess patients with chest pain symptoms using troponin as the only biomarker (m-ADAPT), the Emergency Department Assessment of Chest Pain Score (EDACS) pathway, the History, ECG, Age, Risk Factors, and Troponin (HEART) pathway, the No Objective Testing Rule, and the new Vancouver Chest Pain Rule. Endpoints were 30-day acute myocardial infarction and acute coronary syndrome. Measures of diagnostic accuracy for each rule were calculated. RESULTS: Data included 96 patients (5.3%) with acute myocardial infarction and 139 (7.7%) with acute coronary syndrome. The new Vancouver Chest Pain Rule and No Objective Testing Rule had high sensitivity for acute myocardial infarction (100%; 95% confidence interval [CI] 96.2% to 100% for both) and acute coronary syndrome (98.6% [95% CI 94.9% to 99.8%] and 99.3% [95% CI 96.1% to 100%]). The m-ADAPT, EDACS, and HEART pathways also yielded high sensitivity for acute myocardial infarction (96.9% [95% CI 91.1% to 99.4%] for m-ADAPT and 97.9% [95% CI 92.7% to 99.7%] for EDACS and HEART), but lower sensitivity for acute coronary syndrome (≤95.0% for all). The m-ADAPT, EDACS, and HEART rules classified more patients as being at low risk (64.3%, 62.5%, and 49.8%, respectively) than the new Vancouver Chest Pain Rule and No Objective Testing Rule (28.2% and 34.5%, respectively). CONCLUSION: In this cohort with a low prevalence of acute myocardial infarction and acute coronary syndrome, using the Beckman's Access high-sensitivity troponin I assay with the new Vancouver Chest Pain Rule or No Objective Testing Rule enabled approximately one third of patients to be safely discharged after 2-hour risk stratification with no further testing. The EDACS, m-ADAPT, or HEART pathway enabled half of ED patients to be rapidly referred for objective testing.

Rapid Rule-out of Acute Myocardial Infarction With a Single High-Sensitivity Cardiac Troponin T Measurement Below the Limit of Detection: A Collaborative Meta-analysis.

Background: High-sensitivity assays for cardiac troponin T (hs-cTnT) are sometimes used to rapidly rule out acute myocardial infarction (AMI). Purpose: To estimate the ability of a single hs-cTnT concentration below the limit of detection (<0.005 µg/L) and a nonischemic electrocardiogram (ECG) to rule out AMI in adults presenting to the emergency department (ED) with chest pain. Data Sources: EMBASE and MEDLINE without language restrictions (1 January 2008 to 14 December 2016). Study Selection: Cohort studies involving adults presenting to the ED with possible acute coronary syndrome in whom an ECG and hs-cTnT measurements were obtained and AMI outcomes adjudicated during initial hospitalization. Data Extraction: Investigators of studies provided data on the number of low-risk patients (no new ischemia on ECG and hs-cTnT measurements <0.005 µg/L) and the number who had AMI during hospitalization (primary outcome) or a major adverse cardiac event (MACE) or death within 30 days (secondary outcomes), by risk classification (low or not low risk). Two independent epidemiologists rated risk of bias of studies. Data Synthesis: Of 9241 patients in 11 cohort studies, 2825 (30.6%) were classified as low risk. Fourteen (0.5%) low-risk patients had AMI. Sensitivity of the risk classification for AMI ranged from 87.5% to 100% in individual studies. Pooled estimated sensitivity was 98.7% (95% CI, 96.6% to 99.5%). Sensitivity for 30-day MACEs ranged from 87.9% to 100%; pooled sensitivity was 98.0% (CI, 94.7% to 99.3%). No low-risk patients died. Limitation: Few studies, variation in timing and methods of reference standard troponin tests, and heterogeneity of risk and prevalence of AMI across studies. Conclusion: A single hs-cTnT concentration below the limit of detection in combination with a nonischemic ECG may successfully rule out AMI in patients presenting to EDs with possible emergency acute coronary syndrome. Primary Funding Source: Emergency Care Foundation.

Understanding cardiac troponin part 1: avoiding troponinitis.

Cardiac troponin (cTn) is a highly specific biomarker of myocardial injury and is central to the diagnosis of acute myocardial infarction (AMI). By itself, however, cTn cannot identify the cause of myocardial injury. 'Troponinitis' is the condition that leads clinicians to falsely assign a diagnosis of AMI based only on the fact that a patient has an elevated cTn concentration. There are many causes of myocardial injury other than AMI. Clinicians are required to differentiate myocardial injury caused by AMI from other causes.In part 1 of this series on cTn, we provide a structured overview to help practising clinicians to interpret 'positive' cTn results appropriately. There are three core principles. First, when reviewing a cTn result, clinicians must carefully consider the clinical context. Only this can distinguish primary (termed type 1) AMI caused by coronary artery disease from secondary (termed type 2) AMI caused by another condition with an imbalance in the supply and demand of oxygen to the myocardium. Second, clinicians must consider the patient's baseline condition in order to determine the presence or absence of factors that may predict a chronic cTn elevation. Third, clinicians should routinely use serial sampling to detect a change of cTn that is expected in patients with acute (rather than chronic) myocardial injury. Using these simple principles, clinicians can avoid underdiagnosis and overdiagnosis of AMI.