Association of QT-Prolonging Medications With Risk of Autopsy-Defined Causes of Sudden Death.

Importance: QT-prolonging medications (QTPMs) are a reported risk factor for sudden cardiac death (SCD) when defined by consensus criteria that presume an arrhythmic cause. The effect of QTPM on autopsy-defined sudden arrhythmic death (SAD) is unknown. Objective: To evaluate the association between QTPM and autopsy-defined SAD vs nonarrhythmic cause of sudden death. Design, Setting, and Participants: This prospective countywide case-control study included World Health Organization-defined (presumed) SCD cases who underwent autopsy as part of the San Francisco Postmortem Systematic Investigation of Sudden Cardiac Death Study (POST SCD) to determine arrhythmic or nonarrhythmic cause, and control deaths due to trauma (hereinafter referred to as trauma controls) in San Francisco County, California, from February 1, 2011, to March 1, 2014. Multivariate regression was used to evaluate the association of QTPM with the risk of presumed SCD, autopsy-defined SAD, and non-SAD compared with trauma controls. Medication exposure, determined by prescription lists and postmortem toxicologic findings, was used to calculate a summative QTPM exposure score (range, 0-20). Data were analyzed from September 1, 2018, to June 15, 2019. Exposure: QT-prolonging medication exposure, as measured by QTPM score (1 indicated low; 2-4, moderate; and >4, high). Main Outcomes and Measures: Death due to trauma, presumed SCD, and autopsy-defined non-SAD and SAD with no postmortem findings of extracardiac cause. Results: A total of 629 patients (mean [SD] age, 61.4 [15.7] years; 439 men [69.8%]) were included, 525 with presumed SCDs and 104 traumatic death controls. Individuals with presumed SCDs had higher exposure and were more likely to be taking any QTPM (291 [55.4%] vs 28 [26.9%]; P < .001) than trauma controls. Use of QTPMs was associated with increased risk of presumed SCD in low (odds ratio [OR], 2.25 [95% CI, 1.03-4.96]; P = .04) and high (OR, 6.70 [95% CI, 1.47-30.67]; P = .01) exposure groups. After autopsy adjudication, use of QTPMs was associated with increased risk of non-SAD (low-risk OR, 2.88 [95% CI, 1.18-6.99; P = .02]; moderate-risk OR, 2.62 [95% CI, 1.20-5.73; P = .02]; and high-risk OR, 14.22 [95% CI, 2.91-69.30; P = .001]) but not SAD in all exposure groups. This association was attenuated by the exclusion of occult overdose non-SADs in the highest exposure group. Conclusions and Relevance: These findings confirm the association between QTPMs and presumed SCD; however, after autopsy, this risk was specific for nonarrhythmic causes of sudden death. Studies using consensus SCD criteria may overestimate the association of QTPMs with the risk of SAD.

A Systematic Review and Qualitative Analysis of Concussion Knowledge amongst Sports Coaches and Match Officials.

Sport-related concussion (SRC) is a public health issue of increasing concern. Sports coaches and match officials are important stakeholders in facilitating early recognition, immediate management and appropriate return-to-play following SRC. This systematic review analyses the current evidence on SRC knowledge amongst sports coaches and match officials. The review was conducted in accordance to PRISMA guideline. A qualitative analysis of knowledge on identification, management, prevention and consequences of SRC as well as return-to-play principles was performed. The Appraisal Tool for Cross-sectional Studies was employed to assess the quality and reliability of each study. Searches were conducted on PubMed, Medline Ovid, Web of Science, CINAHL, SPORTDiscus and Psycinfo. Studies included were primary studies in English published in peer-reviewed journals assessing the level of concussion knowledge or education level amongst coaches, officials or both, regardless of sports or competitive level. A total of 20880 studies were identified, from which 27 were included in this review. There were 26 cross-sectional studies and one randomized controlled trial; 20 assessed SRC knowledge amongst coaches, one considered only officials and six studies assessed both groups. Concussion knowledge amongst coaches and match officials was deemed moderate in most studies, although significant knowledge gaps were identified. There is considerable room for further education on SRC amongst coaches and officials, particularly with the less commonly recognized symptoms of SRC and misconceptions about SRC management and prevention. Beyond knowledge assessment, further investigation should explore the translation of concussion knowledge to on-field management of players with SRC.

Refining the World Health Organization Definition: Predicting Autopsy-Defined Sudden Arrhythmic Deaths Among Presumed Sudden Cardiac Deaths in the POST SCD Study.

BACKGROUND: Conventional definitions of sudden cardiac death (SCD) presume cardiac cause. We studied the World Health Organization-defined SCDs autopsied in the POST SCD study (Postmortem Systematic Investigation of SCD) to determine whether premortem characteristics could identify autopsy-defined sudden arrhythmic death (SAD) among presumed SCDs. METHODS: Between January 2, 2011, and January 4, 2016, we prospectively identified all 615 World Health Organization-defined SCDs (144 witnessed) 18 to 90 years in San Francisco County for medical record review and autopsy via medical examiner surveillance. Autopsy-defined SADs had no extracardiac or acute heart failure cause of death. We used 2 nested sets of premortem predictors-an emergency medical system set and a comprehensive set adding medical record data-to develop Least Absolute Selection and Shrinkage Operator models of SAD among witnessed and unwitnessed cohorts. RESULTS: Of 615 presumed SCDs, 348 (57%) were autopsy-defined SAD. For witnessed cases, the emergency medical system model (area under the receiver operator curve 0.75 [0.67-0.82]) included presenting rhythm of ventricular tachycardia/fibrillation and pulseless electrical activity, while the comprehensive (area under the receiver operator curve 0.78 [0.70-0.84]) added depression. If only ventricular tachycardia/fibrillation witnessed cases (n=48) were classified as SAD, sensitivity was 0.46 (0.36-0.57), and specificity was 0.90 (0.79-0.97). For unwitnessed cases, the emergency medical system model (area under the receiver operator curve 0.68 [0.64-0.73]) included black race, male sex, age, and time since last seen normal, while the comprehensive (area under the receiver operator curve 0.75 [0.71-0.79]) added use of ß-blockers, antidepressants, QT-prolonging drugs, opiates, illicit drugs, and dyslipidemia. If only unwitnessed cases <1 hour (n=59) were classified as SAD, sensitivity was 0.18 (0.13-0.22) and specificity was 0.95 (0.90-0.97). CONCLUSIONS: Our models identify premortem characteristics that can better specify autopsy-defined SAD among presumed SCDs and suggest the World Health Organization definition can be improved by restricting witnessed SCDs to ventricular tachycardia/fibrillation or nonpulseless electrical activity rhythms and unwitnessed cases to <1 hour since last normal, at the cost of sensitivity.

Pilot single-centre cross-sectional study to determine emergency physicians' knowledge and management of sports concussion: an experience from Singapore.

INTRODUCTION: Sports concussion remains challenging to manage despite changes to policy and practice since the 2012 International Consensus Conference on Concussion in Sport. Emergency physicians (EPs) are usually the first line of medical care for athletes in amateur and youth collision sports. This single-centre cross-sectional study aimed to establish EPs' understanding and management of concussion in Singapore. METHODS: An anonymised, 17-item online questionnaire was sent to EPs requesting for information on their clinical experience, training, exposure to concussion cases in the emergency department (ED) and assessed knowledge of the condition. RESULTS: Out of 65 EPs, 52 (80%) responded, 25 (48.1%) of whom were medical officers. Over 90% had not received formal training in concussion management, and 73.1% regularly assessed concussion. 40 (76.9%) EPs recognised that loss of consciousness was not essential for diagnosis and only 24 (46.2%) knew the most common symptom. 26 (50.0%) incorrectly reported that they would perform brain imaging. Among those who indicated onward referral, 29 (55.8%) would refer concussed patients to neurosurgery. There were no significant differences between clinical grade or training in concussion and positive responses for definition, imaging modality or most common symptom of concussion. CONCLUSION: Concussion is a common presentation to EDs in Singapore. However, understanding of the condition, its clinical diagnosis, investigation and onward management is limited. Although EPs reported training in concussion, it is likely to be insufficient. Commencing relevant education programmes for undergraduate and postgraduate medical students may enable progressive acquisition of knowledge and thereby improve patient management in the future.

Randomised comparison of intravenous paracetamol and intravenous morphine for acute traumatic limb pain in the emergency department.

OBJECTIVE: To compare the clinical effectiveness of intravenous paracetamol with intravenous morphine in patients with moderate to severe traumatic limb pain. METHODS: This randomised, double-blind pilot study was conducted in an urban UK emergency department. Patients between 16 and 65 years old with isolated limb trauma and in moderate to severe pain (pain score of 7 or more) received either 1 g intravenous paracetamol or 10 mg intravenous morphine sulphate over 15 min. The primary outcome measure was pain score measured on a visual analogue scale at 0, 5, 15, 30 and 60 min after commencing drug administration. The requirement for rescue analgesia and the frequency of adverse reactions were also recorded. RESULTS: 55 patients were recruited over 10 months. There was no significant difference in analgesic effect between the paracetamol and morphine groups at any time interval. There was no significant difference in the rescue analgesia administered, but there were significantly more adverse reactions in the morphine group. CONCLUSION: Intravenous paracetamol appears to provide a level of analgesia comparable to intravenous morphine in isolated limb trauma. Further larger studies are required.