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his is the sixth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. This summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. Topics covered by systematic reviews include cardiopulmonary resuscitation during transport; approach to resuscitation after drowning; passive ventilation; minimizing pauses during cardiopulmonary resuscitation; temperature management after cardiac arrest; use of diagnostic point-of-care ultrasound during cardiac arrest; use of vasopressin and corticosteroids during cardiac arrest; coronary angiography after cardiac arrest; public-access defibrillation devices for children; pediatric early warning systems; maintaining normal temperature immediately after birth; suctioning of amniotic fluid at birth; tactile stimulation for resuscitation immediately after birth; use of continuous positive airway pressure for respiratory distress at term birth; respiratory and heart rate monitoring in the delivery room; supraglottic airway use in neonates; prearrest prediction of in-hospital cardiac arrest mortality; basic life support training for likely rescuers of high-risk populations; effect of resuscitation team training; blended learning for life support training; training and recertification for resuscitation instructors; and recovery position for maintenance of breathing and prevention of cardiac arrest. Members from 6 task forces have assessed, discussed, and debated the quality of the evidence using Grading of Recommendations Assessment, Development, and Evaluation criteria and generated consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections, and priority knowledge gaps for future research are listed. This is the sixth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. This summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. Topics covered by systematic reviews include cardiopulmonary resuscitation during transport; approach to resuscitation after drowning; passive ventilation; minimizing pauses during cardiopulmonary resuscitation; temperature management after cardiac arrest; use of diagnostic point-of-care ultrasound during cardiac arrest; use of vasopressin and corticosteroids during cardiac arrest; coronary angiography after cardiac arrest; public-access defibrillation devices for children; pediatric early warning systems; maintaining normal temperature immediately after birth; suctioning of amniotic fluid at birth; tactile stimulation for resuscitation immediately after birth; use of continuous positive airway pressure for respiratory distress at term birth; respiratory and heart rate monitoring in the delivery room; supraglottic airway use in neonates; prearrest prediction of in-hospital cardiac arrest mortality; basic life support training for likely rescuers of high-risk populations; effect of resuscitation team training; blended learning for life support training; training and recertification for resuscitation instructors; and recovery position for maintenance of breathing and prevention of cardiac arrest. Members from 6 task forces have assessed, discussed, and debated the quality of the evidence using Grading of Recommendations Assessment, Development, and Evaluation criteria and generated consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections, and priority knowledge gaps for future research are listed.

Importance Emergency research is challenging to do well as it involves time sensitive interventions in unstable patients. There is limited time to obtain informed consent from the patient or their legally authorized representative (LAR). Such research is permitted under exception from informed consent (EFIC) if specific criteria are met, including notification after enrollment. Some question whether the risks of EFIC outweighs its benefits. To date, there is limited empiric information about time to notification (TTN) and rates of withdrawal in such trials. Objective To describe variation in TTN and rates of withdrawal among that patients enrolled in EFIC trials over a twelve-year period. Design We performed post hoc descriptive analyses of data from five trials conducted under EFIC. Setting Emergency medical services and receiving hospitals participating in the Resuscitation Outcomes Consortium in the United States and Canada. Participants Patients with out-of-hospital cardiac arrest or life-threatening traumatic injury. Exposures Notification strategies were specified at each site before initiation of enrollment by a local institutional review board. We monitored TTN within each site centrally throughout each study’s enrollment period. Outcomes TTN was defined as time from randomization to first-reported notification of patient or LAR of enrollment. Withdrawal was defined as patient or LAR opt out of ongoing participation at the time of notification. Results Of 35,442 patients enrolled in five trials, 33,805 had cardiac arrest; and 1636 had traumatic injury. TTN varied overall and by patient outcome. Among those with cardiac arrest, TTN ranged from median (5%ile, 95%ile) of 6 (1,27) days to 28 (2, 53) days across sites. 0.3% of notified patients with cardiac arrest withdrew. Among those with traumatic injury, TTN ranged from 0 (0, 5) days to 36 (5, 68) days across sites. 7.7% of notified patients with traumatic injury withdrew. Conclusions and Relevance There is large variation in TTN in trials conducted under EFIC for emergency research. This may be due to several factors. It may or may not be modifiable. Overall rates of withdrawal are low, which suggests current practices related to EFIC are acceptable to those who have participated in emergency research.

Background Analyses of data recorded by monitor-defibrillators that measure CPR depth with different methods show significant relationships between the process and outcome of CPR. Our objective was to evaluate whether chest compression depth was significantly associated with outcome based on accelerometer-recordings obtained with monitor-defibrillators from a single manufacturer, and to assess whether an accelerometer-based analysis corroborated evidence-based practice guidelines on performance of CPR. Methods and results We included 5434 adult patients treated from seven US and Canadian cities between January 2007 and May 2015. These had mean (SD) age of 64.2 (17.2) years, mean compression depth of 45.9 (12.7) mm, ROSC sustained to ED arrival of 26%, and survival to hospital discharge of 8%. For survival to discharge, the adjusted odds ratios were 1.15 (95% CI, 0.86, 1.55) for cases within 2005 depth range (38–51 mm), and 1.17 (95% CI, 0.91, 1.50) for cases within 2010 depth range (>50 mm) compared to those with an average depth of Conclusions This analysis of patients with OHCA demonstrated that increased chest compression depth measured by accelerometer is associated with better survival. It confirms that current evidence-based recommendations to compress within 50–60 mm are likely associated with greater survival than compressing to another depth.

The objectives of this study were to describe the characteristics, management, and outcomes of patients treated by paramedics for hypoglycemia, and to determine the predictors of hospital admission for these patients within 72 hours of the initial hypoglycemia event.We performed a health record review of paramedic call reports and emergency department records over a 12-month period. We queried prehospital databases to identify cases, which included all patients ⩾18 years with prehospital glucose readings of72 mg/dl (4.0 mmol/L) and excluded terminally ill and cardiac arrest patients. We developed and piloted a standardized data collection tool and obtained consensus on all data definitions before initiation of data extraction by trained investigators. Data analyses included descriptive statistics univariate and logistic regression presented as adjusted odds ratios (aOR) with 95% confidence intervals (95%CI).There were 791 patients with the following characteristics: mean age 56.2, male 52.3%, type 1 diabetes 11.6%, on insulin 43.3%, median initial glucose 54.0 mg/dl (3.0 mmol/L), from home 56.4%. They were treated by advanced care paramedics 80.1%, received intravenous D50 37.8%, intramuscular glucagon 17.8%, oral complex carbs/protein 25.7%, and accepted transport to hospital 70.2%. Among those transported, 134 (24.3%) were initially admitted and four more were admitted within 72 hours. One patient was admitted, discharged, and admitted again within 72 hours. Patients without documented histories of diabetes (aOR 2.35, CI 1.13-4.86), with cardiovascular disease (aOR 1.81, CI 1.10-3.00), on corticosteroids (aOR 4.63, CI 2.15-9.96), on oral hypoglycemic agent(s) (aOR 1.92, CI 1.02-3.62), or those given glucagon (aOR 1.77, CI 1.07-2.93) on scene were more likely to be admitted to hospital, whereas patients on insulin (aOR 0.49, CI 0.27-0.91), able to tolerate complex oral carbs/protein (aOR 0.22, CI 0.10-0.48), with final GCS scores of 15 (aOR 0.53, CI 0.34-0.83), or from public locations (aOR 0.40, CI 0.21-0.75) were less likely to be admitted.There are several patient and prehospital management characteristics which, in combination, could be incorporated into a safe clinical decision tool for patients who present with hypoglycemia.

Background Acute heart failure and exacerbation of chronic obstructive pulmonary disease (COPD) are sometimes difficult to differentiate in the emergency department (ED). Objectives We sought to determine the classification performance of lung point-of-care ultrasound (POCUS) compared with chest x-ray study to identify acute heart failure in an older population. Methods We conducted a cohort study with additional health records review between March and September 2017. We included consecutive patients aged 50 years and older with shortness of breath from suspected acute heart failure or COPD. The reference standard was discharged diagnosis, ED diagnosis with confirmation by another physician, or diagnosis made by health record reviews. We calculated the classification performance of lung POCUS to diagnose acute heart failure as well as that of chest x-ray study, and compared them by exact McNemar test. Results There were 81 patients evaluated with lung POCUS, and 67 had acute heart failure. Emergency physicians identified acute heart failure by lung POCUS with sensitivity of 92.5% (95% confidence interval [CI] 83.4–97.5%) and specificity of 85.7% (95% CI 57.2–98.2%). The radiology reading of chest x-ray study had sensitivity of 63.6% (95% CI 50.9–75.1%) and specificity of 92.9% (95% CI 66.1–99.8%). The sensitivity of lung POCUS was significantly higher than that of chest x-ray study (p = 0.0003). Conclusions Lung POCUS in a real clinical setting was highly sensitive and specific in identifying acute heart failure, and performed better than chest x-ray in an older population.

BACKGROUND: A large, randomized trial showed no significant difference in survival to discharge between cardiopulmonary resuscitation (CPR) strategies of 30 compressions with pause for 2 ventilations per cycle (30:2) and continuous chest compression with asynchronous ventilations (CCC). Data from the same trial suggested that adherence to the intended CPR strategy was associated with significantly greater survival. We sought to determine the adherence rate with intended strategy and then explore the association of adherence with survival to discharge in the Resuscitation Outcomes Consortium (ROC). METHODS: This secondary analysis of data from the ROC included three interventional trials and a prospective registry. We modified an automated software algorithm that classified care as 30:2 or CCC before intubation based on compression segment length (defined as the elapsed time from start of compressions to subsequent pause of ≥2 seconds), number of pauses per minute ≥2 seconds in length and chest compression fraction. Intended CPR strategy for individual agencies was based on study randomization (during trial phase) or local standard of care (during registry phase). We defined CPR delivered as adherent when its classification matched the intended strategy. We characterized adherence with intended strategy across trial and registry periods. We examined its association with survival to hospital discharge using multivariate logistic regression after adjustment for Utstein and other potential confounders. Effect modification with intended strategy was assessed through a multiplicative interaction term. RESULTS: Included were 26,810 adults with out of hospital cardiac arrest, of which 10,942 had an intended strategy of 30:2 and 15,868 an intended strategy of CCC. The automated algorithm classified 12,276 cases as CCC, 7,037 as 30:2 and left 7,497 as unclassified. Adherence to intended strategy was 54.4%; this differed by intended strategy (58.6% for CCC vs 48.3% for 30:2). Overall adherence was less during the registry phase as compared to during the trial phase(s). The association between adherence and survival was modified by treatment arm (CCC OR: 0.72, 95% CI: 0.64–0.81 vs 30:2 OR: 1.05, 95% CI: 0.90–1.22; interaction p-value

Background Cardiopulmonary resuscitation (CPR) improves cardiac arrest survival. Cough CPR, percussion pacing and precordial thump have been reported as alternative CPR techniques. We aimed to summarise in a systematic review the effectiveness of these alternative CPR techniques. Methods We searched Ovid MEDLINE, EMBASE and the Cochrane Library on 24/08/2020. We included randomised controlled trials, observational studies and case series with five or more patients. Two reviewers independently reviewed title and abstracts to identify studies for full-text review, and reviewed bibliographies and ‘related articles’ (using PubMed) of full-texts for further eligible studies. We extracted data and performed risk-of-bias assessments on studies included in the systematic review. We summarised data in a narrative synthesis, and used GRADE to assess evidence certainty. Results We included 23 studies (cough CPR n = 4, percussion pacing n = 4, precordial thump n = 16; one study studied two interventions). Only two (both precordial thump) had a comparator group (‘standard’ CPR). For all techniques evidence certainty was very low. Available evidence suggests that precordial thump does not improve survival to hospital discharge in out-of-hospital cardiac arrest. The review did not find evidence that cough CPR or percussion pacing improve clinical outcomes following cardiac arrest. Conclusion Cough CPR, percussion pacing and precordial thump should not be routinely used in established cardiac arrest. In specific inpatient, monitored settings cough CPR (in conscious patients) or percussion pacing may be attempted at the onset of a potential lethal arrhythmia. These must not delay standard CPR efforts in those who lose cardiac output. PROSPERO registration number CRD42019152925.

We sought to compare the ability of the prehospital Canadian C-Spine Rule to selectively recommend immobilization in sport-related versus non-sport-related injuries and describe sport-related mechanisms of injury.We reviewed data from the prospective paramedic Canadian C-Spine Rule validation and implementation studies in 7 Canadian cities. A trained reviewer further categorized sport-related mechanisms of injury collaboratively with a sport medicine physician using a pilot-tested standardized form. We compared the Canadian C-Spine Rule's recommendation to immobilize sport-related versus non-sport-related patients using Chi-square and relative risk statistics with 95% confidence intervals.There were 201 sport-related patients among the 5,978 included. Sport-related injured patients were younger (mean age 36.2 vs. 42.4) and more predominantly male (60.5% vs. 46.8%) than non-sport-related patients. Paramedics did not miss any C-Spine injury when using the Canadian C-Spine Rule. C-Spine injury rates were similar between sport (2/201; 1.0%) and non-sport-injured patients (47/5,777; 0.8%). The Canadian C-Spine Rule recommended immobilization equally between groups (46.4% vs. 42.5%; RR 1.09 95%CI 0.93-1.28), most commonly resulting from a dangerous mechanism among sport-injured (68.7% vs. 54.5%; RR 1.26 95%CI 1.08-1.47). The most common dangerous mechanism responsible for immobilization in sport was axial load.Although equal proportions of sport and non-sport-related injuries were immobilized, a dangerous mechanism was most often responsible for immobilization in sport-related cases. These findings do not address the potential impact of using the Canadian C-Spine Rule to evaluate collegiate or pro athletes assessed by sport medicine physicians. It does support using the Canadian C-Spine Rule as a tool in sport-injured patients assessed by paramedics.RéSUMé: OBJECTIFS: Nous avons cherché à comparer la capacité préhospitalière de la Canadian C-spine Rule à recommander de façon sélective l’immobilisation dans les blessures liées au sport par rapport aux blessures non liées au sport et à décrire les mécanismes des blessures liés au sport. LES MéTHODES: Nous avons examiné les données des études prospectives de validation et de mise en œuvre de la règle canadienne de la colonne vertébrale dans sept villes canadiennes. Un examinateur qualifié a ensuite classé les mécanismes de blessure liés au sport, en collaboration avec un médecin du sport, à l'aide d'un formulaire standardisé testé dans le cadre d'un projet pilote. Nous avons comparé la recommandation de la Canadian C-Spine Rule d'immobiliser les patients liés au sport par rapport aux patients non liés au sport en utilisant les statistiques du chi carré et du risque relatif avec un intervalle de confiance de 95 %. RéSULTATS: Parmi les 5 978 patients inclus il y avait 201 patients liés au sport. Les patients blessés liés au sport étaient plus jeunes (âge moyen 36,2 ans contre 42,4 ans) et plus majoritairement de sexe masculin (60,5 % contre 46,8 %) que les patients non liés au sport. Les ambulanciers paramédicaux n’ont manqué aucune blessure au rachis cervical lorsqu’ils ont utilisé la Canadian C-spine Rule. Les taux de blessures au rachis cervical étaient semblables chez les patients sportifs (2/201 ; 1,0 %) et non sportifs (47/5 777 ; 0,8 %). La Canadian C-spine Rule recommande l'immobilisation de manière égale entre les groupes (46,4 % contre 42,5 % ; RR 1,09 95 % IC 0,93-1,28), le plus souvent en raison d'un mécanisme dangereux chez les sportifs blessés (68,7 % contre 54,5 % ; RR 1,26 95 % IC 1,08-1,47). Le mécanisme dangereux le plus souvent responsable de l'immobilisation dans le sport était la charge axiale. CONCLUSION: Bien que des proportions égales de blessures sportives et non sportives aient été immobilisées, un mécanisme dangereux était le plus souvent responsable de l'immobilisation dans les cas liés au sport. Ces conclusions n'abordent pas l'impact potentiel de l'utilisation de la Canadian C-spine Rule pour évaluer les athlètes collégiaux ou professionnels évalués par les médecins du sport. Elle est favorable à l'utilisation de la Canadian C-spine Rule comme outil pour les patients blessés par le sport et évalués par les ambulanciers.

Background Sudden cardiac death remains a leading cause of mortality in Canada, resulting in more than 35,000 deaths annually. Most cardiac arrest victims collapse in their own home (85% of the time) and 50% are witnessed by a family member or bystander. Survivors have a quality of life similar to the general population, but the overall survival rate for out-of-hospital cardiac arrest (OHCA) rarely exceeds 8%. Victims are almost four times more likely to survive when receiving bystander CPR, but bystander CPR rates have remained low in Canada over the past decade, not exceeding 15–25% until recently. Telecommunication-assisted CPR instructions have been shown to significantly increase bystander CPR rates, but agonal breathing may be misinterpreted as a sign of life by 9–1-1 callers and telecommunicators, and is responsible for as much as 50% of missed OHCA diagnoses. We sought to improve the ability and speed with which ambulance telecommunicators can recognize OHCA over the phone, initiate timely CPR instructions, and improve survival. Methods In this multi-center national study, we will implement and evaluate an educational program developed for ambulance telecommunicators using a multiple baseline interrupted time-series design. We will compare outcomes 12 months before and after the implementation of a 20-min theory-based educational video addressing barriers to recognition of OHCA while in the presence of agonal breathing. Participating Canadian sites demonstrated prior ability to collect standardized data on OHCA. Data will be collected from eligible 9–1-1 recordings, paramedic documentation and hospital medical records. Eligible cases will include suspected or confirmed OHCA of presumed cardiac origin in patients of any age with attempted resuscitation. Discussion The ability of telecommunication-assisted CPR instructions to improve bystander CPR and survival rates for OHCA victims is undeniable. The ability of telecommunicators to recognize OHCA over the phone is unequivocally impeded by relative lack of training on agonal breathing, and reluctance to initiate CPR instructions when in doubt. Our pilot data suggests the potential impact of this project will be to increase absolute OHCA recognition and bystander CPR rates by at least 10%, and absolute out-of-hospital cardiac arrest survival by 5% or more. Trial registration Prospectively registered on March 28, 2019 at ClinicalTrials.gov identifier: NCT03894059.

The objective of the Canadian Association of Emergency Physicians (CAEP) 2020 Academic Symposium Panel was to present recommendations for collaboration on (1) writing a grant application; (2) conducting a study; (3) writing an abstract; and (4) writing a manuscript. We assembled an expert panel of eight experienced emergency medicine clinician scientists from across Canada. Panel members performed literature searches for each of the four topics. Draft recommendations were developed and refined in an iterative fashion by panel members. We solicited external feedback on the draft recommendations online from identified researchers known to CAEP and in person at the Network of Canadian Emergency Researchers meeting in February 2020. We obtained additional feedback during an online symposium presentation on October 15th, 2020, open to all members of the Canadian Association of Emergency Physicians. Four sets of recommendations were established for each component including: 14 for writing a grant application including relevant timelines; 23 for conducting a study; 13 for writing an abstract; and 18 for writing a manuscript. Forming a strong team, including patients, appropriate methodologists, content experts and a mix of senior and junior investigators, establishing and following clear timelines, and proactive communications were common themes. We offer recommendations for research collaboration for (1) writing a grant, (2) conducting a study, (3) writing an abstract, and (4) writing a manuscript. We believe these recommendations will help to improve the science, improve grant success, and improve the impact of the abstracts and manuscripts.

Failure to rapidly identify bleeding in trauma patients leads to substantial morbidity and mortality. We aimed to develop and validate a simple bedside score for identifying bleeding patients requiring escalation of care beyond initial resuscitation.We included patients with major blunt or penetrating trauma, defined as those with an Injury Severity Score greater than 12 or requiring trauma team activation, at The Ottawa Hospital from September 2014 to September 2017. We used logistic regression for derivation. The primary outcome was a composite of the need for massive transfusion, embolization or surgery for hemostasis. We prespecified clinical, laboratory and imaging predictors using findings from our prior systematic review and survey of Canadian traumatologists. We used an AIC-based stepdown procedure based on the Akaike information criterion and regression coefficients to create a 5-variable score for bedside application. We used bootstrap internal validation to assess optimism-corrected performance.We included 890 patients, of whom 133 required a major intervention. The main model comprised systolic blood pressure, clinical examination findings suggestive of hemorrhage, lactate level, focused assessment with sonography in trauma (FAST) and computed tomographic imaging. The C statistic was 0.95, optimism-corrected to 0.94. A simplified Canadian Bleeding (CAN-BLEED) score was devised. A score cut-off of 2 points yielded sensitivity of 97.7% (95% confidence interval [CI] 93.6 to 99.5) and specificity 73.2% (95% CI 69.9 to 76.3). An alternative version that included mechanism of injury rather than CT had lower discriminative ability (C statistic = 0.89).A simple yet promising bleeding score is proposed to identify highrisk patients in need of major intervention for traumatic bleeding and determine the appropriateness of early transfer to specialized trauma centres. Further research is needed to evaluate the performance of the score in other settings, define interrater reliability and evaluate the potential for reduction of time to intervention.Les délais dans la détection des saignements actifs chez les patients en traumatologie entraînent une morbidité et une mortalité élevées. L’objectif était d’élaborer et de valider une échelle simple, à utiliser en contexte clinique pour repérer les patients qui présentent un saignement actif et qui nécessitent une intensification des soins après la réanimation initiale.Les critères d’inclusion étaient les suivants : admission à l’Hôpital d’Ottawa entre septembre 2014 et septembre 2017 pour un traumatisme contondant ou pénétrant, et score de gravité de la blessure supérieur à 12 ou mobilisation de l’équipe de traumatologie. Nous avons fait la dérivation par régression logistique. Le principal critère d’évaluation était la nécessité d’une transfusion massive, d’une embolisation ou d’une opération pour rétablir l’hémostase. Nous avons établi les facteurs prédictifs décelables en clinique, en laboratoire et à l’imagerie en fonction des résultats que nous avons obtenus dans le cadre d’une revue systématique et d’un sondage mené auprès de traumatologues canadiens. Nous avons utilisé une procédure avec ajustement selon le critère d’information d’Akaike (AIC) et des coefficients de régression afin de créer une échelle à 5 variables applicable en contexte clinique. Pour ce qui est de la validation interne, nous avons ajusté les valeurs dites « optimistes » à l’aide de la méthode d’autoamorçage (bootstrap).Nous avons inclus 890 patients, dont 133 nécessitaient une intervention majeure. Le modèle de base intégrait la pression artérielle systolique, les constatations cliniques indiquant une hémorragie, le taux de lactate, les résultats de l’échographie ciblée en traumatologie (FAST) et les résultats de la tomodensitométrie (TMD). La statistique C s’élevait à 0,95 (0,94 après ajustement). Nous avons conçu une échelle canadienne simplifiée d’évaluation des saignements actifs (CANBLEED). Un seuil de 2 points a généré une sensibilité de 97,7 % (intervalle de confiance [IC] à 95 % de 93,6 à 99,5) et une spécificité de 73,2 % (IC à 95 % de 69,9 à 76,3). Une deuxième version, qui tient compte du mécanisme de blessure plutôt que des résultats de la TMD, avait un pouvoir de discrimination inférieur (statistique C = 0,89).Nous proposons une échelle d’évaluation des saignements actifs simple, mais prometteuse. Celle-ci vise à repérer les patients à haut risque qui nécessitent une intervention majeure pour un saignement d’origine traumatique ainsi qu’à déterminer la pertinence d’un transfert précoce dans un centre de traumatologie. Des études complémentaires seront nécessaires afin d’évaluer l’échelle dans d’autres milieux, d’établir sa fiabilité interévaluateurs et d’évaluer le potentiel de réduction des délais d’intervention.

Objective We evaluated the effect of chest compression fraction (CCF) on survival to hospital discharge and return of spontaneous circulation (ROSC) in out-of-hospital cardiac arrest (OHCA) patients with non-shockable rhythms. Methods This is a retrospective analysis (completed in 2016) of a prospective cohort study which included OHCA patients from ten U.S. and Canadian sites (Resuscitation Outcomes Consortium Epistry and PRIMED study (2007–2011)). We included all OHCA victims of presumed cardiac aetiology, not witnessed by emergency medical services (EMS), without automated external defibrillator shock prior to EMS arrival, receiving > 1 min of CPR with CPR process measures available, and initial non-shockable rhythm. We measured CCF using the first 5 min of electronic CPR records. Results Demographics of 12,928 adult patients were: mean age 68; male 59.9%; public location 8.5%; bystander witnessed 35.2%; bystander CPR 39.3%; median interval from 911 to defibrillator turned on 10 min:04 s; initial rhythm asystole 64.8%, PEA 26.0%, other non-shockable 9.2%; compression rate 80−120/min (69.1%); median CCF 74%; ROSC 25.6%; survival to hospital discharge 2.4%. Adjusted odds ratio (OR); 95% confidence intervals (95%CI) of survival for each CCF category were: 0−40% (2.00; 1.16, 3.32); 41−60% (0.83; 0.54, 1.24); 61−80% (1.02; 0.77, 1.35); and 81−100% (reference group). Adjusted (OR; 95%CI) of ROSC for each CCF category were: 0−40% (1.02; 0.79, 1.30); 41−60% (0.83; 0.72, 0.95); 61−80% (0.85; 0.77, 0.94); and 81−100% (reference group). Conclusions We observed an incremental benefit from higher CCF on the incidence of ROSC, but not survival, among non-shockable OHCA patients with CCF higher than 40%.

International audience; Aims: There are large differences between emergency medical systems, which may account for variability in outcomes. We seek to compare prehospital organizations, response modes, patient characteristics and outcomes after out-of-hospital cardiac arrest, between France and Canada, and discuss the need for the first European-North American prehospital research network on out-of-hospital cardiac arrest.Methods: Preliminary comparative description of data drawn from two nation-wide, population-based, Utstein-style prospectively implemented registries for out-of-hospital cardiac arrest in France and Canada (France: RéAC, Canada: CanROC), covering approximately 80 million people, and soon to be participating in an international research network in 2020.Results: Since creation, 103,722 cases were included in France and approximately 99,317 in Canada. Data used in this work were drawn from 2011 to 2016, and comprised around 33,688 adult, non-traumatic, treated cases in Canada, and 55,358 in France, leading to estimated incidence rates of 75.3/100,000 inhabitants in France and 83/100,000 in Canada. In both countries, out-of-hospital cardiac arrest predominantly occurred in male patients, in their late sixties, at home, of presumed cardiac aetiology. Bystander cardiopulmonary resuscitation was provided in half of the cases. First assessed cardiac rhythm was shockable in 16% (France) vs. 22% (Canada). Professional resuscitation was attempted in 82% (France) and 60% (Canada). Prehospital organizations and response modes differed in the constitution of responding teams (France: physician-led advanced life support, Canada: trained paramedics), in response time intervals (call to first professional responders' arrival at scene 6.5 min (interquartile range IQR [5.2-8.3]) (Canada) vs. 10 min [7-15] (France)), in on-scene interventions, type of referral at hospital (France: systematic bypass of emergency department, tertiary hospital first, Canada: occasional bypass, mainly closest hospital first), and in outcomes (overall survival at hospital discharge in France: 5% vs. Canada: 11%).Conclusion: Despite similarities in some out-of-hospital cardiac arrest Utstein variables, several differences exist between French and Canadian prehospital systems, and ultimately, between outcomes. The creation of the ReACanROC research network will facilitate the conduction of further analyses to better understand predictors of this variability.

BackgroundIn many EDs, emergency physicians (EPs) do not have admitting privileges and must wait for consultants to further assess and admit patients. This delays bed requests and increases ED crowding. We measured EPs’ abilities to predict patient admission prior to consultation and estimated the potential ED stretcher time saved if EPs requested a bed with consultation.MethodsWe conducted a prospective cohort study in an academic centre in Canada between October 2017 and February 2018 using a convenience sample of ED patient encounters requiring consultation. We excluded patients under 18 years or those clearly likely to be admitted (traumas, strokes, S-T elevation myocardial infarctions and Canadian Triage and Acuity Scale of 1). EPs predicted patient admission just before consultation. Potential ED stretcher time saved was estimated for correctly predicted admissions assuming bed requests were initiated with consultation and a constant time to inpatient bed.ResultsCharacteristics of 454 patients were: mean age 60.1 years, 48.5% male, 46.9% evening presentation, 69.4% admitted and median time to bed request of 3.5 hours (IQR 2.0–5.3 hours). Overall, EPs prediction sensitivity, specificity, positive predictive value and negative predictive value were 90.5% (95% CI 86.7% to 93.5%), 84.2% (95% CI 77.0% to 89.8%), 92.8% (95% CI 89.8% to 95.0%) and 79.6% (95% CI 73.4% to 84.7%). Approximately 922.1 hours of ED stretcher time could have been saved during the 5-month study period if EPs initiated a bed request with consultation.ConclusionCrowding is a reality for EDs worldwide, and many systems could benefit from EP-initiated hospital admissions to decrease the amount of time admitted patients wait in the ED.

The Canadian C-spine rule was modified and validated for use by the paramedics in a multicenter study where patients were assessed with the Canadian C-spine rule yet all transported with immobilization. This study evaluated the clinical impact of the modified Canadian C-spine rule when implemented by paramedics.This single-center prospective cohort implementation study took place in Ottawa, Canada (from 2011 to 2015). Advanced and primary care paramedics were trained to use the modified Canadian C-spine rule, collect data on a standardized study form, and selectively transport eligible patients without immobilization. We evaluated all consecutive low-risk adult patients (Glasgow Coma Scale [GCS] 15, stable vital signs) at risk for a neck injury. We followed all patients without initial radiologic evaluation for 30 days. Analyses included descriptive statistics with 95% confidence intervals (CI), sensitivity, specificity, and kappa coefficients.The 4,034 enrolled patients had a mean age of 43 (range 16 to 99), and 53.4% were female. Motor vehicle collisions were the most common mechanism of injury (55.1%), followed by falls (23.9%). There were 11 clinically important injuries. The paramedics classified these injuries with a sensitivity of 90.9% (95% CI, 58.7 to 99.8) and specificity of 66.5% (95% CI, 65.1 to 68.0). There was no adverse event or resulting spinal cord injury. The kappa agreement between paramedics and investigators was 0.94. A total of 2,583 (64.0%) immobilizations were avoided using the modified Canadian C-spine rule.Paramedics could accurately apply the modified Canadian C-spine rule to low-risk trauma patients and significantly reduce the need for spinal immobilization during transport. This resulted in no adverse event or any spinal cord injury.

ObjectiveClinical trials for patients with shock-refractory out-of-hospital cardiac arrest (OHCA), including the Amiodarone, Lidocaine or Placebo (ALPS) trial, have been unable to demonstrate definitive benefit after treatment with antiarrhythmic drugs. A Bayesian approach, combining the available evidence, may yield additional insights.MethodsWe conducted a reanalysis of the ALPS trial comparing treatment with amiodarone or lidocaine with placebo in patients with OHCA following shock-refractory ventricular fibrillation or ventricular tachycardia (VF/VT). We used Bayesian regression to assess the probability of improved survival or improved neurological outcome on the 7-point modified Rankin Scale. We derived weak, moderate and strong priors from a previous clinical trial.ResultsThe original ALPS trial randomised 3026 adult patients with OHCA to amiodarone (n=974, survival to hospital discharge 24.4%), lidocaine, (n=993, survival 23.7%) or placebo (n=1059, survival 21.0%). In our reanalysis the probability of improved survival from amiodarone ranged from 83% (strong prior) to 95% (weak prior) compared with placebo and from 78% (strong) to 90% (weak) for lidocaine—an estimated improvement in survival of 2.9% (IQR 1.4%–3.8%) for amiodarone and 1.7% (IQR 0.84%–3.2%) for lidocaine over placebo (moderate prior). The probability of improved neurological outcome from amiodarone ranged from 96% (weak) to 99% (strong) compared with placebo and from 88% (weak) to 96% (strong) for lidocaine.ConclusionsIn a Bayesian reanalysis of patients with shock-resistant VF/VT OHCA, treatment with amiodarone had high probabilities of improved survival and neurological outcome, while treatment with lidocaine had a more modest benefit.

Background Research priority setting in health care has historically been done by expert health care providers and researchers and has not involved patients, family or the public. Survivors & family members have been particularly absent from this process in the field of resuscitation research and specifically adult out of hospital cardiac arrest (OHCA). As such, we sought to conduct a priority setting exercise in partnership with survivors, lay responders and their families in order to ensure that their priorities were visible. We partnered with the James Lind Alliance (UK) and used their commonly used consensus methodology for Public Priority Setting Partnerships (PSPs) to identify research priorities that reflected the perspectives of all stakeholders. Methods We used two rounds of public and health care professional surveys to create the initial priority lists. The initial survey collected open-ended questions while the second round consolidated the list of initial questions into a refined list for prioritization. This was done by reviewing existing evidence and thematic categorization by the multi-disciplinary steering committee. An in-person consensus workshop was conducted to come to consensus on the top ten priorities from all perspectives. The McMaster PPEET tool was used to measure engagement. Results The initial survey yielded more than 425 responses and 1450 “questions” from survivors and family members (18%), lay responders, health care providers and others. The second survey asked participants to rank a short list of 125 questions. The final top 25 questions were brought to the in-person meeting, and a top ten were selected through the JLA consensus process. The final list of top ten questions included how to improve the rate of lay responder CPR, what interventions used at the scene of an arrest can improve resuscitation and survival, how survival can be improved in rural areas of Canada, what resuscitation medications are most effective, what care patient’s family members need, what post-discharge support is needed for survivors, how communication should work for everyone involved with a cardiac arrest, what factors best predict neurologically intact survival, whether biomarkers/genetic tests are effective in predicting OHCA and more research on the short and long-term psycho-social impacts of OHCA on survivors. The PPEET showed overwhelmingly positive results for the patient and family engagement experience during the final workshop. Conclusions This inclusive research priority setting provides essential information for those doing resuscitation research internationally. The results provide a guide for priority areas of research and should drive our community to focus on questions that matter to survivors and their families in our work. In particular the Canadian Resuscitation Outcomes Consortium will be incorporating the top ten list into its strategic plan for the future.

The management of pain is an important component of care in the prehospital and transport setting. However, recent evidence suggests that pain control is infrequently achieved in these settings. The objective of the current study was to determine the proportion and frequency of opioid analgesia provided to intubated patients during interfacility transport by an air medical transport system.This was a health records review examining electronic records of intubated patients transported by Ornge from July 2015 to November 2015. Cases were identified using Ornge database, and intubated patients were selected based on the inclusion criteria. A standardized data extraction form was piloted and used by a single trained data extractor. The primary outcome was whether analgesia was provided. Secondary outcomes included the frequency of administration and dose adequacy of an opioid analgesia; the analgesic used; adverse events; and the impact of age, sex, past medical history of chronic pain, or reason for transfer on pain management.Of the 500 potential patient transports, 448 met our inclusion criteria. Among the 448 patients, 295 (65.8%) were men, 327 (73.0%) received analgesia, and 211 (64.3%) received more than 1 dose during transport (median frequency of 2 doses, interquartile range = 1 to 3). The average transport time was 135 minutes, and repeated dosing (1 repeat dose) occurred primarily (45.5%) in transports of over 180 minutes. Fentanyl was the most commonly used analgesic (97.9%), and the most common dose was 50 µg (51.8%). Adverse events occurred in 8 patients (2.5%), most commonly new hypotension (mean arterial pressure65 mm Hg, n = 5). There was no significant difference in the administration of analgesia based on the patient's age or sex (68.0% of female patients and 75.6% of male patients received analgesia). Interestingly, only 30.8% of patients repatriated to their originating hospital received analgesia compared with 72.3% of patients undergoing their initial transfer to a higher level of care.Seventy-three percent of intubated patients transported by Ornge received an opioid analgesic, most commonly fentanyl. We found no clinically relevant difference in the administration of analgesics based on age, sex, past medical history of chronic pain, or reason for transfer other than repatriation to the originating hospital.

Background\ud \ud Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) has been reported in individual studies to significantly increase the rate of bystander CPR and survival from cardiac arrest.\ud \ud Methods \ud \ud We undertook a systematic review and meta-analysis to evaluate the impact of DA-CPR programs on key clinical outcomes following out-of-hospital cardiac arrest. We searched the PubMED, EMBASE, CINAHL, ERIC and Cochrane Central Register of Controlled Trials databases from inception until July 2018. Eligible studies compared systems with and without dispatcher-assisted CPR programs. Included studies were divided into three groups: comparison of outcomes in systems providing DA-CPR; comparison of cases where DA-CPR was provided to cases where bystander CPR was ongoing, and DA-CPR was not provided; and comparison of cases where DA-CPR was provided to cases where no bystander CPR was provided (patient level comparisons). The GRADE system was used to assess certainty of evidence at an outcome level. We used random-effects models to produce summary effect sizes across all outcomes.\ud \ud Results \ud \ud Of 5,531 citations screened, 33 studies were eligible for inclusion. All included studies were observational. Evidence certainty across all outcomes was assessed as low or very low. In system-level and patient-level comparisons, the provision of DA-CPR compared with no DA-CPR was consistently associated with improved outcome across all analyses. Comparison of DA-CPR to bystander CPR produced conflicting results. Findings were consistent across sensitivity analyses and the pediatric sub-group.\ud \ud Conclusion \ud \ud These results support the recommendation that dispatchers provide CPR instructions to callers for adults and children with suspected OHCA.\ud

International audience; France and Canada prehospital systems and care delivery in out-of-hospital cardiac arrests (OHCAs) show substantial differences. This article aims to describe the rationale, design, implementation and expected research implications of the international, population-based, France-Canada registry for OHCAs, namely ReACanROC, which is built from the merging of two nation-wide, population-based, Utstein-style prospectively implemented registries for OHCAs attended to by emergency medical services. Under the supervision of an international steering committee and research network, the ReACanROC dataset will be used to run in-depth analyses on the differences in organisational, practical and geographic predictors of survival after OHCA between France and Canada. ReACanROC is the first Europe-North America registry ever created to meet this goal. To date, it covers close to 80 million people over the two countries, and includes approximately 200 000 cases over a 10-year period.

BackgroundIn 2020, there were 4,352 people waiting for organ transplantation in Canada. A rise in demand has led to national exploration of non-traditional pathways for organ donation to increase the potential pool of donors and subsequent transplant recipients. Donation after Cardiac Death (DCD) has become a promising option across Canada and in other jurisdictions worldwide. One unexplored aspect to uncontrolled DCD (uDCD) in Canada is the inclusion of patients who suffer an out-of-hospital cardiac arrest (OHCA) into the pool of potential donors, of which there are an estimated 40,000 each year in Canada. The primary objective of this study is to quantify the potential pool of donors that would be eligible for uDCD subsequent to OHCA. This will allow us to understand how many potential donors are being missed when treated, but not transported after an OHCA.MethodsA retrospective observational cohort study will be undertaken, using pre-existing data from the Canadian Resuscitation Outcomes Consortium (CanROC) registry, a pan- Canadian registry that collects prospective OHCA data. Consecutive OHCA cases from January 1, 2016 - December 31, 2018 meeting inclusion criteria will be included.ResultsDescriptive analysis will be used to examine patient and event characteristics, and determine the proportion of patients who meet the indication for uDCD. Results will be reported as mean (standard deviation [SD]) or median (interquartile range [IQR]) for continuous variables and frequency (%) for categorical variables.ConclusionsPreliminary literature review suggests uDCD subsequent to OHCA is a viable opportunity to increase the donor pool in Canada. Presently, there is a lack of understanding of this pool of potential donors, and no programs exist in Canada to recruit from this population. In order to determine if pursuing uDCD subsequent to OHCA to improve organ donation rates is worthwhile, we must first quantify its potential.

Targeted temperature management (TTM) may improve survival and functional outcome in comatose survivors of out-of-hospital cardiac arrest (OHCA), though the optimal target temperature remains unknown. We conducted a systematic review and network meta-analysis to investigate the efficacy and safety of deep hypothermia (31–32 °C), moderate hypothermia (33–34 °C), mild hypothermia (35–36 °C), and normothermia (37–37.8 °C) during TTM. We searched six databases from inception to June 2021 for randomized controlled trials (RCTs) evaluating TTM in comatose OHCA survivors. Two reviewers performed screening, full text review, and extraction independently. The primary outcome of interest was survival with good functional outcome. We used GRADE to rate our certainty in estimates. We included 10 RCTs (4218 patients). Compared with normothermia, deep hypothermia (odds ratio [OR] 1.30, 95% confidence interval [CI] 0.73–2.30), moderate hypothermia (OR 1.34, 95% CI 0.92–1.94) and mild hypothermia (OR 1.44, 95% CI 0.74–2.80) may have no effect on survival with good functional outcome (all low certainty). Deep hypothermia may not improve survival with good functional outcome, as compared to moderate hypothermia (OR 0.97, 95% CI 0.61–1.54, low certainty). Moderate hypothermia (OR 1.23, 95% CI 0.86–1.77) and deep hypothermia (OR 1.27, 95% CI 0.70–2.32) may have no effect on survival, as compared to normothermia. Finally, incidence of arrhythmia was higher with moderate hypothermia (OR 1.45, 95% CI 1.08–1.94) and deep hypothermia (OR 3.58, 95% CI 1.77–7.26), compared to normothermia (both high certainty). Mild, moderate, or deep hypothermia may not improve survival or functional outcome after OHCA, as compared to normothermia. Moderate and deep hypothermia were associated with higher incidence of arrhythmia. Routine use of moderate or deep hypothermia in comatose survivors of OHCA may potentially be associated with more harm than benefit.

The objective of the Canadian Association of Emergency Physicians (CAEP) 2020 Academic Symposium Panel was to present recommendations for collaboration on (1) writing a grant application; (2) conducting a study; (3) writing an abstract; and (4) writing a manuscript.We assembled an expert panel of eight experienced emergency medicine clinician scientists from across Canada. Panel members performed literature searches for each of the four topics. Draft recommendations were developed and refined in an iterative fashion by panel members. We solicited external feedback on the draft recommendations online from identified researchers known to CAEP and in person at the Network of Canadian Emergency Researchers meeting in February 2020. We obtained additional feedback during an online symposium presentation on October 15th, 2020, open to all members of the Canadian Association of Emergency Physicians.Four sets of recommendations were established for each component including: 14 for writing a grant application including relevant timelines; 23 for conducting a study; 13 for writing an abstract; and 18 for writing a manuscript. Forming a strong team, including patients, appropriate methodologists, content experts and a mix of senior and junior investigators, establishing and following clear timelines, and proactive communications were common themes.We offer recommendations for research collaboration for (1) writing a grant, (2) conducting a study, (3) writing an abstract, and (4) writing a manuscript. We believe these recommendations will help to improve the science, improve grant success, and improve the impact of the abstracts and manuscripts.RéSUMé: OBJECTIF: L'objectif du comité d’experts du symposium académique 2020 de l’Association canadienne des médecins d’urgence (ACMU) était de présenter des recommandations de collaboration sur (1) la rédaction d’une demande de subvention; (2) l’accomplissement d’une étude; (3) la rédaction d’un résumé; et (4) la rédaction d’un manuscrit. MéTHODES: Nous avons réuni un comité d'experts de huit cliniciens-chercheurs en médecine d’urgence dotés d’expérience de partout au Canada. Les membres du comité ont effectué des recherches documentaires sur chacun des quatre sujets. Des projets de recommandations ont été élaborés et affinés de manière itérative par les membres du comité. Nous avons sollicité en ligne des remarques externes sur les projets de recommandations des chercheurs connus de l’ACMU (CAEP) ainsi que des chercheurs connus en personne lors de la réunion du Réseau des chercheurs d’urgence canadienne en février 2020. Nous avons obtenu des remarques supplémentaires lors d'une présentation du symposium en ligne le 15 octobre 2020, ouvert à tous les membres de l'Association canadienne des médecins d'urgence. RéSULTATS: Quatre séries de recommandations ont été établies pour chaque composante, dont: 14 pour la rédaction d'une demande de subvention, y compris les délais pertinents; 23 pour mener une étude; 13 pour rédiger un résumé; et 18 pour la rédaction d'un manuscrit. La formation d'une équipe solide, comprenant des patients, des méthodologistes appropriés, des experts en contenu et un mélange de chercheurs principaux et chercheurs assistants, l'établissement et le respect de calendriers clairs et des communications proactives étaient des thèmes communs. CONCLUSION: Nous proposons des recommandations de collaboration de recherche pour (1) rédiger une subvention, (2) mener une étude, (3) rédiger un résumé et (4) rédiger un manuscrit. Nous croyons que ces recommandations contribueront à améliorer la science, à renforcer le succès des subventions et à bonifier l'impact des résumés et des manuscrits.

This 2020 International Consensus on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care Science With Treatment Recommendations on basic life support summarizes evidence evaluations performed for 20 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 3 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review. Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest. The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.

This 2020 International Consensus on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care Science With Treatment Recommendations on basic life support summarizes evidence evaluations performed for 22 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 5 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review. Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest. The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.

ObjectivesWe aimed to determine the rate of adverse events during interfacility transport of cardiac patients identified as low risk by a consensus-derived screening tool and transported by primary care flight paramedics (PCP(f)).MethodsWe conducted a health records review of adult patients diagnosed with a cardiac condition who were identified as low risk by the screening tool and transported by PCP(f). We excluded patients transported by an advanced care crew, those accompanied by a clinical escort from hospital, and those transported from a scene call, by rotary wing or ground vehicle. We recorded patient and transportation parameters using a piloted-standardized collection tool. We defined adverse events during transport a priori. We report descriptive statistics using mean (standard deviation), [range], (percentage).ResultsWe included 400 patients: mean age 66.9 years old, 66.5% male. Mean transport duration was 136.2 (74.9) minutes. Most common comorbidities were hypertension (50.3%) and coronary artery disease (39.5%). Most transports originated out of Northern Ontario and were for cardiac catheterization (61.8%) or coronary artery bypass grafting (26.8%). Overall, the adverse event rate was low (0.3%), with no serious event such as cardiac arrest, death, or airway intervention.ConclusionsA screening tool can identify cardiac patients at low risk for clinical deterioration during air-medical transport. We believe patients screened with this tool can be transported safely by a PCP(f) crew, leading to potentially significant resource savings.

OBJECTIVE Having shown promise in other medical fields, we sought to determine whether machine learning (ML) models perform better than usual care in diagnostic and prognostic prediction for emergency department (ED) patients. METHODS In this systematic review, we searched MEDLINE, Embase, Central, and CINAHL from inception to October 17, 2019. We included studies comparing diagnostic and prognostic prediction of ED patients by ML models to usual care methods (triage-based scores, clinical prediction tools, clinician judgment) using predictor variables readily available to ED clinicians. We extracted commonly reported performance metrics of model discrimination and classification. We used the PROBAST tool for risk of bias assessment (PROSPERO registration: CRD42020158129). RESULTS The search yielded 1,656 unique records, of which 23 studies involving 16,274,647 patients were included. In all seven diagnostic studies, ML models outperformed usual care in all performance metrics. In six studies assessing in-hospital mortality, the best-performing ML models had better discrimination (area under the receiver operating characteristic curve [AUROC] =0.74-0.94) than any clinical decision tool (AUROC =0.68-0.81). In four studies assessing hospitalization, ML models had better discrimination (AUROC =0.80-0.83) than triage-based scores (AUROC =0.68-0.82). Clinical heterogeneity precluded meta-analysis. Most studies had high risk of bias due to lack of external validation, low event rates, and insufficient reporting of calibration. CONCLUSIONS Our review suggests that ML may have better prediction performance than usual care for ED patients with a variety of clinical presentations and outcomes. However, prediction model reporting guidelines should be followed to provide clinically applicable data. Interventional trials are needed to assess the impact of ML models on patient-centered outcomes.

Emergency medical services (EMS) is called for a 65-year-old man with a 1-week history of cough, fever, and mild shortness of breath now reporting chest pain. Vitals on scene were HR 110, BP 135/90, SpO2 88% on room air. EMS arrives at the emergency department (ED). As the patient is moved to a negative pressure room, he becomes unresponsive with no palpable pulse. What next steps should be discussed in order to protect the team and achieve the best possible patient outcome?

Aim To summarize the prognostic associations of pre- and intra-arrest factors with return of spontaneous circulation (ROSC) and survival (in-hospital or 30 days) after traumatic out-of-hospital cardiac arrest. Methods We conducted this review in accordance with the PRISMA and CHARMS guidelines. We searched Medline, Pubmed, Embase, Scopus, Web of Science and the Cochrane Database of Systematic Reviews from inception through December 1st, 2019. We included English language studies evaluating pre- and intra-arrest prognostic factors following penetrating or blunt traumatic OHCA. Risk of bias was assessed using the QUIPS tool. We pooled unadjusted odds ratios using random-effects models and presented adjusted odds ratios with 95% confidence intervals. We used the GRADE method to describe certainty. Results We included 53 studies involving 37,528 patients. The most important predictors of survival were presence of cardiac motion on ultrasound (odds ratio 33.91, 1.87–613.42, low certainty) or a shockable initial cardiac rhythm (odds ratio 7.29, 5.09–10.44, moderate certainty), based on pooled unadjusted analyses. Importantly, mechanism of injury was not associated with either ROSC (odds ratio 0.97, 0.51–1.85, very low certainty) or survival (odds ratio 1.40, 0.79–2.48, very low certainty). Conclusion This review provides very low to moderate certainty evidence that pre- and intra-arrest prognostic factors following penetrating or blunt traumatic OHCA predict ROSC and survival. This evidence is primarily based on unadjusted data. Further well-designed studies with larger cohorts are warranted to test the adjusted prognostic ability of pre- and intra-arrest factors and guide therapeutic decision-making.