Predicting Out-of-Hospital Cardiac Arrest in the General Population Using Electronic Health Records.

BACKGROUND: The majority of out-of-hospital cardiac arrests (OHCAs) occur among individuals in the general population, for whom there is no established strategy to identify risk. In this study, we assess the use of electronic health record (EHR) data to identify OHCA in the general population and define salient factors contributing to OHCA risk. METHODS: The analytical cohort included 2366 individuals with OHCA and 23 660 age- and sex-matched controls receiving health care at the University of Washington. Comorbidities, electrocardiographic measures, vital signs, and medication prescription were abstracted from the EHR. The primary outcome was OHCA. Secondary outcomes included shockable and nonshockable OHCA. Model performance including area under the receiver operating characteristic curve and positive predictive value were assessed and adjusted for observed rate of OHCA across the health system. RESULTS: There were significant differences in demographic characteristics, vital signs, electrocardiographic measures, comorbidities, and medication distribution between individuals with OHCA and controls. In external validation, discrimination in machine learning models (area under the receiver operating characteristic curve 0.80-0.85) was superior to a baseline model with conventional cardiovascular risk factors (area under the receiver operating characteristic curve 0.66). At a specificity threshold of 99%, correcting for baseline OHCA incidence across the health system, positive predictive value was 2.5% to 3.1% in machine learning models compared with 0.8% for the baseline model. Longer corrected QT interval, substance abuse disorder, fluid and electrolyte disorder, alcohol abuse, and higher heart rate were identified as salient predictors of OHCA risk across all machine learning models. Established cardiovascular risk factors retained predictive importance for shockable OHCA, but demographic characteristics (minority race, single marital status) and noncardiovascular comorbidities (substance abuse disorder) also contributed to risk prediction. For nonshockable OHCA, a range of salient predictors, including comorbidities, habits, vital signs, demographic characteristics, and electrocardiographic measures, were identified. CONCLUSIONS: In a population-based case-control study, machine learning models incorporating readily available EHR data showed reasonable discrimination and risk enrichment for OHCA in the general population. Salient factors associated with OCHA risk were myriad across the cardiovascular and noncardiovascular spectrum. Public health and tailored strategies for OHCA prediction and prevention will require incorporation of this complexity.

Prediction of Shock-Refractory Ventricular Fibrillation During Resuscitation of Out-of-Hospital Cardiac Arrest.

BACKGROUND: Out-of-hospital cardiac arrest due to shock-refractory ventricular fibrillation (VF) is associated with relatively poor survival. The ability to predict refractory VF (requiring ≥3 shocks) in advance of repeated shock failure could enable preemptive targeted interventions aimed at improving outcome, such as earlier administration of antiarrhythmics, reconsideration of epinephrine use or dosage, changes in shock delivery strategy, or expedited invasive treatments. METHODS: We conducted a cohort study of VF out-of-hospital cardiac arrest to develop an ECG-based algorithm to predict patients with refractory VF. Patients with available defibrillator recordings were randomized 80%/20% into training/test groups. A random forest classifier applied to 3-s ECG segments immediately before and 1 minute after the initial shock during cardiopulmonary resuscitation was used to predict the need for ≥3 shocks based on singular value decompositions of ECG wavelet transforms. Performance was quantified by area under the receiver operating characteristic curve. RESULTS: Of 1376 patients with VF out-of-hospital cardiac arrest, 311 (23%) were female, 864 (63%) experienced refractory VF, and 591 (43%) achieved functional neurological survival. Total shock count was associated with decreasing likelihood of functional neurological survival, with a relative risk of 0.95 (95% CI, 0.93-0.97) for each successive shock (P<0.001). In the 275 test patients, the area under the receiver operating characteristic curve for predicting refractory VF was 0.85 (95% CI, 0.79-0.89), with specificity of 91%, sensitivity of 63%, and a positive likelihood ratio of 6.7. CONCLUSIONS: A machine learning algorithm using ECGs surrounding the initial shock predicts patients likely to experience refractory VF, and could enable rescuers to preemptively target interventions to potentially improve resuscitation outcome.

Epidemiology of Covid-19 in a Long-Term Care Facility in King County, Washington.

BACKGROUND: Long-term care facilities are high-risk settings for severe outcomes from outbreaks of Covid-19, owing to both the advanced age and frequent chronic underlying health conditions of the residents and the movement of health care personnel among facilities in a region. METHODS: After identification on February 28, 2020, of a confirmed case of Covid-19 in a skilled nursing facility in King County, Washington, Public Health-Seattle and King County, aided by the Centers for Disease Control and Prevention, launched a case investigation, contact tracing, quarantine of exposed persons, isolation of confirmed and suspected cases, and on-site enhancement of infection prevention and control. RESULTS: As of March 18, a total of 167 confirmed cases of Covid-19 affecting 101 residents, 50 health care personnel, and 16 visitors were found to be epidemiologically linked to the facility. Most cases among residents included respiratory illness consistent with Covid-19; however, in 7 residents no symptoms were documented. Hospitalization rates for facility residents, visitors, and staff were 54.5%, 50.0%, and 6.0%, respectively. The case fatality rate for residents was 33.7% (34 of 101). As of March 18, a total of 30 long-term care facilities with at least one confirmed case of Covid-19 had been identified in King County. CONCLUSIONS: In the context of rapidly escalating Covid-19 outbreaks, proactive steps by long-term care facilities to identify and exclude potentially infected staff and visitors, actively monitor for potentially infected patients, and implement appropriate infection prevention and control measures are needed to prevent the introduction of Covid-19.

Burnout and Workplace Incivility Among Emergency Medical Services Practitioners: A Preliminary Report.

OBJECTIVE: Burnout has detrimental consequences for health care organizations, clinicians, and the quality of care that patients receive. Prior work suggests that workplace incivility (negative interpersonal acts) contributes to burnout. While workplace incivility is linked to EMS practitioner job dissatisfaction, absenteeism, and planned attrition, the relationship between workplace incivility and burnout has not been evaluated among EMS practitioners. This study aimed to characterize the prevalence and association of burnout and workplace incivility among EMS practitioners. METHODS: A cross-sectional survey of EMS personnel in King County, Washington was performed in January to March of 2021 with burnout as the primary outcome and workplace incivility as a secondary outcome. Multivariable logistic regression was used to evaluate associations between outcomes and EMS practitioner factors that included age, sex, race/ethnicity, years of EMS experience, and current job role. RESULTS: 835 completed surveys were received (response rate 25%). The prevalence of burnout was 39.2%. Women were more likely to have burnout than men (59.3% vs. 33.7%, aOR 2.2, 95% CI 1.3-3.7). Workplace incivility was experienced weekly by 32.1% of respondents, with women more likely to experience incivility compared to men (41.9% vs. 27.2%, aOR 2.0, 95% CI 1.2-3.3). Respondents who experienced frequent workplace incivility were more likely to have burnout than those who did not experience frequent incivility (61.9% vs. 38.1%, OR 4.0, 95% CI 3.0-5.5). CONCLUSIONS: The prevalence of burnout and workplace incivility were concerning among EMS practitioners, with women more likely to experience both compared to men. EMS practitioners who experienced frequent workplace incivility were also more likely to have burnout than those who did not experience frequent incivility.

Instantaneous amplitude: Association of ventricular fibrillation waveform measures at time of shock with outcome in out-of-hospital cardiac arrest.

BACKGROUND: Prompt defibrillation is key to successful resuscitation from ventricular fibrillation out-of-hospital cardiac arrest (VF-OHCA). Preliminary evidence suggests that the timing of shock relative to the amplitude of the VF ECG waveform may affect the likelihood of resuscitation. We investigated whether the VF waveform amplitude at the time of shock (instantaneous amplitude) predicts outcome independent of other validated waveform measures. METHODS: We conducted a retrospective study of VF-OHCA patients ≥18 old. We evaluated three VF waveform measures for each shock: instantaneous amplitude at the time of shock, and maximum amplitude and amplitude spectrum area (AMSA) over a 3-s window preceding the shock. Linear mixed-effects modeling was used to determine whether instantaneous amplitude was associated with shock-specific return of organized rhythm (ROR) or return of spontaneous circulation (ROSC) independent of maximum amplitude or AMSA. RESULTS: The 566 eligible patients received 1513 shocks, resulting in ROR of 62.0% (938/1513) and ROSC of 22.3% (337/1513). In unadjusted regression, an interquartile increase in instantaneous amplitude was associated with ROR (Odds ratio [OR] [95% confidence interval] = 1.27 [1.11-1.45]) and ROSC (OR = 1.27 [1.14-1.42]). However, instantaneous amplitude was not associated with ROR (OR = 1.13 [0.97-1.30]) after accounting for maximum amplitude, nor with ROR (OR = 1.00 [0.87-1.15]) or ROSC (OR = 1.05 [0.93-1.18]) after accounting for AMSA. By contrast, AMSA and maximum amplitude remained independently associated with ROR and ROSC. CONCLUSIONS: We did not observe an independent association between instantaneous amplitude and shock-specific outcomes. Efforts to time shock to the maximal amplitude of the VF waveform are unlikely to affect resuscitation outcome.

Survival After Intravenous Versus Intraosseous Amiodarone, Lidocaine, or Placebo in Out-of-Hospital Shock-Refractory Cardiac Arrest.

BACKGROUND: Antiarrhythmic drugs have not proven to significantly improve overall survival after out-of-hospital cardiac arrest from shock-refractory ventricular fibrillation/pulseless ventricular tachycardia. How this might be influenced by the route of drug administration is not known. METHODS: In this prespecified analysis of a randomized, placebo-controlled clinical trial, we compared the differences in survival to hospital discharge in adults with shock-refractory ventricular fibrillation/pulseless ventricular tachycardia out-of-hospital cardiac arrest who were randomly assigned by emergency medical services personnel to an antiarrhythmic drug versus placebo in the ALPS trial (Resuscitation Outcomes Consortium Amiodarone, Lidocaine or Placebo Study), when stratified by the intravenous versus intraosseous route of administration. RESULTS: Of 3019 randomly assigned patients with a known vascular access site, 2358 received ALPS drugs intravenously and 661 patients by the intraosseous route. Intraosseous and intravenous groups differed in sex, time-to-emergency medical services arrival, and some cardiopulmonary resuscitation characteristics, but were similar in others, including time-to-intravenous/intrasosseous drug receipt. Overall hospital discharge survival was 23%. In comparison with placebo, discharge survival was significantly higher in recipients of intravenous amiodarone (adjusted risk ratio, 1.26 [95% CI, 1.06-1.50]; adjusted absolute survival difference, 5.5% [95% CI, 1.5-9.5]) and intravenous lidocaine (adjusted risk ratio, 1.21 [95% CI, 1.02-1.45]; adjusted absolute survival difference, 4.7% [95% CI, 0.7-8.8]); but not in recipients of intraosseous amiodarone (adjusted risk ratio, 0.94 [95% CI, 0.66-1.32]) or intraosseous lidocaine (adjusted risk ratio, 1.03 [95% CI, 0.74-1.44]). Survival to hospital admission also increased significantly when drugs were given intravenously but not intraosseously, and favored improved neurological outcome at discharge. There were no outcome differences between intravenous and intraosseous placebo, indicating that the access route itself did not demarcate patients with poor prognosis. The study was underpowered to assess intravenous/intraosseous drug interactions, which were not statistically significant. CONCLUSIONS: We found no significant effect modification by drug administration route for amiodarone or lidocaine in comparison with placebo during out-of-hospital cardiac arrest. However, point estimates for the effects of both drugs in comparison with placebo were significantly greater for the intravenous than for the intraosseous route across virtually all outcomes and beneficial only for the intravenous route. Given that the study was underpowered to statistically assess interactions, these findings signal the potential importance of the drug administration route during resuscitation that merits further investigation.

Occupational exposures and programmatic response to COVID-19 pandemic: an emergency medical services experience.

Rigorous assessment of occupational COVID-19 risk and personal protective equipment (PPE) use is not well-described. We evaluated 9-1-1 emergency medical services (EMS) encounters for patients with COVID-19 to assess occupational exposure, programmatic strategies to reduce exposure and PPE use. We conducted a retrospective cohort investigation of laboratory-confirmed patients with COVID-19 in King County, Washington, USA, who received 9-1-1 EMS responses from 14 February 2020 to 26 March 2020. We reviewed dispatch, EMS and public health surveillance records to evaluate the temporal relationship between exposure and programmatic changes to EMS operations designed to identify high-risk patients, protect the workforce and conserve PPE. There were 274 EMS encounters for 220 unique COVID-19 patients involving 700 unique EMS providers with 988 EMS person-encounters. Use of 'full' PPE including mask (surgical or N95), eye protection, gown and gloves (MEGG) was 67%. There were 151 person-exposures among 129 individuals, who required 981 quarantine days. Of the 700 EMS providers, 3 (0.4%) tested positive within 14 days of encounter, though these positive tests were not attributed to occupational exposure from inadequate PPE. Programmatic changes were associated with a temporal reduction in exposures. When stratified at the study encounters midpoint, 94% (142/151) of exposures occurred during the first 137 EMS encounters compared with 6% (9/151) during the second 137 EMS encounters (p<0.01). By the investigation's final week, EMS deployed MEGG PPE in 34% (3579/10 468) of all EMS person-encounters. Less than 0.5% of EMS providers experienced COVID-19 illness within 14 days of occupational encounter. Programmatic strategies were associated with a reduction in exposures, while achieving a measured use of PPE.

Impact of Regionalization of ST-Segment-Elevation Myocardial Infarction Care on Treatment Times and Outcomes for Emergency Medical Services-Transported Patients Presenting to Hospitals With Percutaneous Coronary Intervention: Mission: Lifeline Accelerator-2.

BACKGROUND: Regional variations in reperfusion times and mortality in patients with ST-segment-elevation myocardial infarction are influenced by differences in coordinating care between emergency medical services (EMS) and hospitals. Building on the Accelerator-1 Project, we hypothesized that time to reperfusion could be further reduced with enhanced regional efforts. METHODS: Between April 2015 and March 2017, we worked with 12 metropolitan regions across the United States with 132 percutaneous coronary intervention-capable hospitals and 946 EMS agencies. Data were collected in the ACTION (Acute Coronary Treatment and Intervention Outcomes Network)-Get With The Guidelines Registry for quarterly Mission: Lifeline reports. The primary end point was the change in the proportion of EMS-transported patients with first medical contact to device time ≤90 minutes from baseline to final quarter. We also compared treatment times and mortality with patients treated in hospitals not participating in the project during the corresponding time period. RESULTS: During the study period, 10 730 patients were transported to percutaneous coronary intervention-capable hospitals, including 974 in the baseline quarter and 972 in the final quarter who met inclusion criteria. Median age was 61 years; 27% were women, 6% had cardiac arrest, and 6% had shock on admission; 10% were black, 12% were Latino, and 10% were uninsured. By the end of the intervention, all process measures reflecting coordination between EMS and hospitals had improved, including the proportion of patients with a first medical contact to device time of ≤90 minutes (67%-74%; P<0.002), a first medical contact to device time to catheterization laboratory activation of ≤20 minutes (38%-56%; P<0.0001), and emergency department dwell time of ≤20 minutes (33%-43%; P<0.0001). Of the 12 regions, 9 regions reduced first medical contact to device time, and 8 met or exceeded the national goal of 75% of patients treated in ≤90 minutes. Improvements in treatment times corresponded with a significant reduction in mortality (in-hospital death, 4.4%-2.3%; P=0.001) that was not apparent in hospitals not participating in the project during the same time period. CONCLUSIONS: Organization of care among EMS and hospitals in 12 regions was associated with significant reductions in time to reperfusion in patients with ST-segment-elevation myocardial infarction as well as in in-hospital mortality. These findings support a more intensive regional approach to emergency care for patients with ST-segment-elevation myocardial infarction.

Inclined position is associated with improved first pass success and laryngoscopic view in prehospital endotracheal intubations.

PURPOSE: In hospital-based studies, patients intubated by physicians while in an inclined position compared to supine position had a higher rate of first pass success and lower rate of peri-intubation complications. We evaluated the impact of patient positioning on prehospital endotracheal intubation in an EMS system with rapid sequence induction capability. We hypothesized that patients in the inclined position would have a higher first-pass success rate. METHODS: Prehospital endotracheal intubation cases performed by paramedics between 2012 and 2017 were prospectively collected in airway registries maintained by a metropolitan EMS system. We included all adult (age ≥ 18 years) non-traumatic, non-arrest patients who received any attempt at intubation. Patients were categorized according to initial positioning: supine or inclined. The primary outcome measure was first pass success with secondary outcomes of laryngoscopic view and challenges to intubation. RESULTS: Of the 13,353 patients with endotracheal intubation attempted by paramedics during the study period, 4879 were included for analysis. Of these, 1924 (39.4%) were intubated in the inclined position. First pass success was 86.3% among the inclined group versus 82.5% for the supine group (difference 3.8%, 95% CI: 1.5%-6.1%). First attempt laryngeal grade I view was 62.9% in the inclined group versus 57.1% for the supine group (difference 5.8%, 2.0-9.6). Challenges to intubation were more frequent in the supine group (42.3% versus 38.8%, difference 3.5%, 0.6-6.3). CONCLUSION: Inclined positioning was associated with a better grade view and higher rate of first pass success. The technique should be considered as a viable approach for prehospital airway management.

Trial of Continuous or Interrupted Chest Compressions during CPR.

BACKGROUND: During cardiopulmonary resuscitation (CPR) in patients with out-of-hospital cardiac arrest, the interruption of manual chest compressions for rescue breathing reduces blood flow and possibly survival. We assessed whether outcomes after continuous compressions with positive-pressure ventilation differed from those after compressions that were interrupted for ventilations at a ratio of 30 compressions to two ventilations. METHODS: This cluster-randomized trial with crossover included 114 emergency medical service (EMS) agencies. Adults with non-trauma-related cardiac arrest who were treated by EMS providers received continuous chest compressions (intervention group) or interrupted chest compressions (control group). The primary outcome was the rate of survival to hospital discharge. Secondary outcomes included the modified Rankin scale score (on a scale from 0 to 6, with a score of ≤3 indicating favorable neurologic function). CPR process was measured to assess compliance. RESULTS: Of 23,711 patients included in the primary analysis, 12,653 were assigned to the intervention group and 11,058 to the control group. A total of 1129 of 12,613 patients with available data (9.0%) in the intervention group and 1072 of 11,035 with available data (9.7%) in the control group survived until discharge (difference, -0.7 percentage points; 95% confidence interval [CI], -1.5 to 0.1; P=0.07); 7.0% of the patients in the intervention group and 7.7% of those in the control group survived with favorable neurologic function at discharge (difference, -0.6 percentage points; 95% CI, -1.4 to 0.1, P=0.09). Hospital-free survival was significantly shorter in the intervention group than in the control group (mean difference, -0.2 days; 95% CI, -0.3 to -0.1; P=0.004). CONCLUSIONS: In patients with out-of-hospital cardiac arrest, continuous chest compressions during CPR performed by EMS providers did not result in significantly higher rates of survival or favorable neurologic function than did interrupted chest compressions. (Funded by the National Heart, Lung, and Blood Institute and others; ROC CCC ClinicalTrials.gov number, NCT01372748.).

Syringe Administration of Epinephrine by Emergency Medical Technicians for Anaphylaxis.

OBJECTIVE: In recent years, the costs of epinephrine autoinjectors (EAIs) in the United States have risen substantially. King County Emergency Medical Services implemented the "Check and Inject" program to replace EAIs by teaching emergency medical technicians (EMTs) to manually aspirate epinephrine from a single-use 1 mg/mL epinephrine vial using a needle and syringe followed by prehospital intramuscular administration of the correct adult or pediatric dose of epinephrine for anaphylaxis or serious allergic reaction. Treatment was guided by an EMT protocol that required a trigger and symptoms. We sought to determine if the "Check and Inject" program was safely implemented by EMTs treating presumed prehospital anaphylaxis or serious allergic reaction. METHODS: We conducted a prospective investigation of all cases treated as part of the "Check and Inject" program from July 2014 through December 2016 in suburban King County, Washington, and January 2016 through December 2016 within the city of Seattle. All cases were prospectively collected using a custom quality improvement data form completed by the first responding EMTs. Two physicians completed a structured review of each EMS medical record to determine if the EMTs followed the Check and Inject protocol and determine if epinephrine was clinically-indicated based on physician review. RESULTS: Of the 411 cases eligible for analysis, EMTs followed the protocol appropriately in 367 (89.3%) cases. In the remaining 44 (10.7%) cases, the EMS incident report form failed to document either a clear inciting allergic trigger or an appropriate symptom from the protocol list. Physician review determined that epinephrine was clinically indicated in 36 of the 44 cases. Among the remaining 8 cases (1.9%) that did not meet protocol criteria and were not clinically-indicated based on physician review, none had a documented adverse reaction to the epinephrine. CONCLUSION: We observed that EMTs successfully implemented the manual "Check and Inject" program for severe allergic reactions and anaphylaxis in a manner that typically agreed with physician review and without any overt identified safety issues.

Ventricular fibrillation waveform measures combined with prior shock outcome predict defibrillation success during cardiopulmonary resuscitation.

AIM: Amplitude Spectrum Area (AMSA) and Median Slope (MS) are ventricular fibrillation (VF) waveform measures that predict defibrillation shock success. Cardiopulmonary resuscitation (CPR) obscures electrocardiograms and must be paused for analysis. Studies suggest waveform measures better predict subsequent shock success when combined with prior shock success. We determined whether this relationship applies during CPR. METHODS: AMSA and MS were calculated from 5-second pre-shock segments with and without CPR, and compared to logistic models combining each measure with prior return of organized rhythm (ROR). RESULTS: VF segments from 692 patients were analyzed during CPR before 1372 shocks and without CPR before 1283 shocks. Combining waveform measures with prior ROR increased areas under receiver operating characteristic curves for AMSA/MS with CPR (0.66/0.68 to 0.73/0.74, p<0.001) and without CPR (0.71/0.72 to 0.76/0.76, p<0.001). CONCLUSIONS: Prior ROR improves prediction of shock success during CPR, and may enable waveform measure calculation without chest compression pauses.

Physician Variation in Time to Antimicrobial Treatment for Septic Patients Presenting to the Emergency Department.

OBJECTIVES: Delayed initiation of appropriate antimicrobials is linked to higher sepsis mortality. We investigated interphysician variation in septic patients' door-to-antimicrobial time. DESIGN: Retrospective cohort study. SETTING: Emergency department of an academic medical center. SUBJECTS: Adult patients treated with antimicrobials in the emergency department between 2009 and 2015 for fluid-refractory severe sepsis or septic shock. Patients who were transferred, received antimicrobials prior to emergency department arrival, or were treated by an attending physician who cared for less than five study patients were excluded. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We employed multivariable linear regression to evaluate the association between treating attending physician and door-to-antimicrobial time after adjustment for illness severity (Acute Physiology and Chronic Health Evaluation II score), patient age, prehospital or arrival hypotension, admission from a long-term care facility, mode of arrival, weekend or nighttime admission, source of infection, and trainee involvement in care. Among 421 eligible patients, 74% received antimicrobials within 3 hours of emergency department arrival. After covariate adjustment, attending physicians' (n = 40) median door-to-antimicrobial times varied significantly, ranging from 71 to 359 minutes (p = 0.002). The percentage of each physician's patients whose antimicrobials began within 3 hours of emergency department arrival ranged from 0% to 100%. Overall, 12% of variability in antimicrobial timing was explained by the attending physician compared with 4% attributable to illness severity as measured by the Acute Physiology and Chronic Health Evaluation II score (p < 0.001). Some but not all physicians started antimicrobials later for patients who were normotensive on presentation (p = 0.017) or who had a source of infection other than pneumonia (p = 0.006). The adjusted odds of in-hospital mortality increased by 20% for each 1 hour increase in door-to-antimicrobial time (p = 0.046). CONCLUSIONS: Among patients with severe sepsis or septic shock receiving antimicrobials in the emergency department, door-to-antimicrobial times varied five-fold among treating physicians. Given the association between antimicrobial delay and mortality, interventions to reduce physician variation in antimicrobial initiation are likely indicated.

Early Identification of Patients With Out-of-Hospital Cardiac Arrest With No Chance of Survival and Consideration for Organ Donation.

BACKGROUND: In patients with out-of-hospital cardiac arrest (OHCA), care requirements can conflict with the need to promptly focus efforts on organ donation in patients who are pronounced dead. OBJECTIVE: To evaluate objective criteria for identifying patients with OHCA with no chance of survival during the first minutes of cardiopulmonary resuscitation to enable prompt orientation toward organ donation. DESIGN: Retrospective assessment using OHCA data from 2 registries and 1 trial. SETTING: France (Paris Sudden Death Expertise Center [SDEC] prospective cohort [2011 to 2014] and PRESENCE multicenter cluster randomized trial [ClinicalTrials.gov: NCT01009606] [2009 to 2011]) and the United States (King County, Washington, prospective cohort [2006 to 2011]). PATIENTS: 1771 patients from the Paris SDEC 1-year cohort (2011 to 2012) and 5192 from the validation cohorts. MEASUREMENTS: Evaluation of 3 objective criteria (OHCA not witnessed by emergency medical services personnel, nonshockable initial cardiac rhythm, and no return of spontaneous circulation before receipt of a third 1-mg dose of epinephrine), survival rate at hospital discharge among patients meeting these criteria, performance of the criteria, and number of patients eligible for organ donation. RESULTS: In the Paris SDEC 1-year cohort, the survival rate among the 772 patients with OHCA who met the objective criteria was 0% (95% CI, 0.0% to 0.5%), with a specificity of 100% (CI, 97% to 100%) and a positive predictive value of 100% (CI, 99% to 100%). These results were verified in the validation cohorts. Ninety-five (12%) patients in the Paris SDEC 1-year cohort may have been eligible for organ donation. LIMITATION: Several patients had unknown outcomes. CONCLUSION: Three objective criteria enable the early identification of patients with OHCA with essentially no chance of survival and may help in decision making about the organ donation process. PRIMARY FUNDING SOURCE: French Ministry of Health.

American Heart Association Response to the 2015 Institute of Medicine Report on Strategies to Improve Cardiac Arrest Survival.

The American Heart Association (AHA) commends the recently released Institute of Medicine (IOM) report, Strategies to Improve Cardiac Arrest Survival: A Time to Act (2015). The AHA recognizes the unique opportunity created by the report to meaningfully advance the objectives of improving outcomes for sudden cardiac arrest. For decades, the AHA has focused on the goal of reducing morbidity and mortality from cardiovascular disease though robust support of basic, translational, clinical, and population research. The AHA also has developed a rigorous process using the best available evidence to develop scientific, advisory, and guideline documents. These core activities of development and dissemination of scientific evidence have served as the foundation for a broad range of advocacy initiatives and programs that serve as a foundation for advancing the AHA and IOM goal of improving cardiac arrest outcomes. In response to the call to action in the IOM report, the AHA is announcing 4 new commitments to increase cardiac arrest survival: (1) The AHA will provide up to $5 million in funding over 5 years to incentivize resuscitation data interoperability; (2) the AHA will actively pursue philanthropic support for local and regional implementation opportunities to increase cardiac arrest survival by improving out-of-hospital and in-hospital systems of care; (3) the AHA will actively pursue philanthropic support to launch an AHA resuscitation research network; and (4) the AHA will cosponsor a National Cardiac Arrest Summit to facilitate the creation of a national cardiac arrest collaborative that will unify the field and identify common goals to improve survival. In addition to the AHA's historic and ongoing commitment to improving cardiac arrest care and outcomes, these new initiatives are responsive to each of the IOM recommendations and demonstrate the AHA's leadership in the field. However, successful implementation of the IOM recommendations will require a timely response by all stakeholders identified in the report and a coordinated approach to achieve our common goal of improved cardiac arrest outcomes.

In the Wrong Place with the Wrong SNP: The Association Between Stressful Neighborhoods and Cardiac Arrest Within Beta-2-adrenergic Receptor Variants.

BACKGROUND: Sudden cardiac arrest has been linked independently both to stressful neighborhood conditions and to polymorphisms in the ADRB2 gene. The ADRB2 gene mediates sympathetic activation in response to stress. Therefore, if neighborhood conditions cause cardiac arrest through the stress pathway, the ADRB2 variant may modify the association between neighborhood conditions, such as socioeconomic deprivation and incidence of cardiac arrest. METHODS: The Cardiac Arrest Blood Study Repository is a population-based repository of specimens and other data from adult cardiac arrest patients residing in King County, Washington. Cases (n = 1,539) were 25- to 100-year-old individuals of European descent who experienced out-of-hospital cardiac arrest from 1988 to 2004. Interactions between neighborhood conditions and the ADRB2 genotype on cardiac arrest risk were assessed in a case-only study design. Gene-environment independence was assessed in blood samples obtained from King County residents initially contacted by random-digit dialing. RESULTS: Fewer than 4% of study subjects resided in socioeconomically deprived neighborhoods. Nonetheless, the case-only analysis indicated the presence of supramultiplicative interaction of socioeconomic deprivation and the homozygous Gln27Glu variant (case-only odds ratio: 1.8 [95% confidence interval: 1.0, 2.9]). Interactions between population density and the homozygous Gln27Glu variant were weaker (case-only odds ratio: 1.2 [95% confidence interval: 0.97, 1.5]). CONCLUSIONS: Findings support a supramultiplicative interaction between the Gln27Glu ADRB2 variant and socioeconomic deprivation among individuals of European descent. This result is consistent with the hypothesis that the elevation in cardiac arrest risk associated with socioeconomic deprivation operates through the stress pathway.

Pediatric Intubation by Paramedics in a Large Emergency Medical Services System: Process, Challenges, and Outcomes.

STUDY OBJECTIVE: Pediatric intubation is a core paramedic skill in some emergency medical services (EMS) systems. The literature lacks a detailed examination of the challenges and subsequent adjustments made by paramedics when intubating children in the out-of-hospital setting. We undertake a descriptive evaluation of the process of out-of-hospital pediatric intubation, focusing on challenges, adjustments, and outcomes. METHODS: We performed a retrospective analysis of EMS responses between 2006 and 2012 that involved attempted intubation of children younger than 13 years by paramedics in a large, metropolitan EMS system. We calculated the incidence rate of attempted pediatric intubation with EMS and county census data. To summarize the intubation process, we linked a detailed out-of-hospital airway registry with clinical records from EMS, hospital, or autopsy encounters for each child. The main outcome measures were procedural challenges, procedural success, complications, and patient disposition. RESULTS: Paramedics attempted intubation in 299 cases during 6.3 years, with an incidence of 1 pediatric intubation per 2,198 EMS responses. Less than half of intubations (44%) were for patients in cardiac arrest. Two thirds of patients were intubated on the first attempt (66%), and overall success was 97%. The most prevalent challenge was body fluids obscuring the laryngeal view (33%). After a failed first intubation attempt, corrective actions taken by paramedics included changing equipment (33%), suctioning (32%), and repositioning the patient (27%). Six patients (2%) experienced peri-intubation cardiac arrest and 1 patient had an iatrogenic tracheal injury. No esophageal intubations were observed. Of patients transported to the hospital, 86% were admitted to intensive care and hospital mortality was 27%. CONCLUSION: Pediatric intubation by paramedics was performed infrequently in this EMS system. Although overall intubation success was high, a detailed evaluation of the process of intubation revealed specific challenges and adjustments that can be anticipated by paramedics to improve first-pass success, potentially reduce complications, and ultimately improve clinical outcomes.

Development and validation of a prehospital prediction model for acute traumatic coagulopathy.

BACKGROUND: Acute traumatic coagulopathy (ATC) is a syndrome of early, endogenous clotting dysfunction that afflicts up to 30% of severely injured patients, signaling an increased likelihood of all-cause and hemorrhage-associated mortality. To aid identification of patients within the likely therapeutic window for ATC and facilitate study of its mechanisms and targeted treatment, we developed and validated a prehospital ATC prediction model. METHODS: Construction of a parsimonious multivariable logistic regression model predicting ATC - defined as an admission international normalized ratio >1.5 - employed data from 1963 severely injured patients admitted to an Oregon trauma system hospital between 2008 and 2012 who received prehospital care but did not have isolated head injury. The prediction model was validated using data from 285 severely injured patients admitted to a level 1 trauma center in Seattle, WA, USA between 2009 and 2013. RESULTS: The final Prediction of Acute Coagulopathy of Trauma (PACT) score incorporated age, injury mechanism, prehospital shock index and Glasgow Coma Score values, and prehospital cardiopulmonary resuscitation and endotracheal intubation. In the validation cohort, the PACT score demonstrated better discrimination (area under the receiver operating characteristic curve 0.80 vs. 0.70, p = 0.032) and likely improved calibration compared to a previously published prehospital ATC prediction score. Designating PACT scores ≥196 as positive resulted in sensitivity and specificity for ATC of 73% and 74%, respectively. CONCLUSIONS: Our prediction model uses routinely available and objective prehospital data to identify patients at increased risk of ATC. The PACT score could facilitate subject selection for studies of targeted treatment of ATC.

Impact of Building Height and Volume on Cardiac Arrest Response Time.

Emergency medical services (EMS) care may be delayed when out-of-hospital cardiac arrest (OHCA) occurs in tall or large buildings. We hypothesized that larger building height and volume were related to a longer curb-to-defibrillator activation interval. We retrospectively evaluated 3,065 EMS responses to OHCA in a large city between 2003-13 that occurred indoors, prior to EMS arrival, and without prior deployment of a defibrillator. The two-tiered EMS system uses automated external defibrillator-equipped basic life support firefighters followed by paramedics dispatched from a single call center. We calculated three time intervals obtained from the computerized dispatch report and time-synchronized defibrillators: initial 911 call to address curb arrival by first unit (call-to-curb), curb arrival to defibrillator power on (curb-to-defib on), and the combined call-to-defib on interval. Building height and surface area were measured with a validated program based on aerial photography. Buildings were categorized by height as short (<25 ft), medium (26-64 ft) and tall (>64 ft). Volume was categorized as small (<60,000 ft(3)), midsize (60,000-1,202,600 ft(3)) and large (>1,202,600 ft(3)). Intervals were compared using the two-tailed Mann-Whitney test. EMS responded to 1,673 OHCA events in short, 1,134 in medium, and 258 in tall buildings. There was a 1.14 minute increase in median curb-to-defib on interval from 1.97 in short to 3.11 minutes in tall buildings (p < 0.01). Taller buildings, however, had a shorter call-to-curb interval (4.73 for short vs 3.96 minutes for tall, p < 0.01), such that the difference in call-to-defib on interval was only 0.27 minutes: 6.87 for short and 7.14 for tall buildings. A similar relationship was observed for small-volume compared to large-volume building: longer curb-to-AED (1.90 vs. 3.01 minutes, p < 0.01), but shorter call-to-curb (4.87 vs. 4.05, p < 0.01); the difference in call-to-defib on was 0.18 minutes. Both taller and larger-volume buildings had longer curb-to-AED intervals but shorter 911 call-to-curb arrival intervals. As a consequence, building height and volume had a modest overall relationship with interval from call to defibrillator application. These results do not support the hypothesis that either taller or larger-volume buildings need cause poorer outcomes in urban environments.