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Background: Quantitative measures of the ventricular fibrillation (VF) ECG waveform can assess myocardial physiology and predict cardiac arrest outcomes, making these measures a candidate to help guide resuscitation. Chest compressions are typically paused for waveform measure calculation because compressions cause ECG artifact. However, such pauses contradict resuscitation guideline recommendations to minimize cardiopulmonary resuscitation interruptions. We evaluated a comprehensive group of VF measures with and without ongoing compressions to determine their performance under both conditions for predicting functionally-intact survival, the study's primary outcome., Methods: Five-second VF ECG segments were collected with and without chest compressions before 2755 defibrillation shocks from 1151 out-of-hospital cardiac arrest patients. Twenty-four individual measures and 3 combination measures were implemented. Measures were optimized to predict functionally-intact survival (Cerebral Performance Category score ≤2) using 460 training cases, and their performance evaluated using 691 independent test cases., Results: Measures predicted functionally-intact survival on test data with an area under the receiver operating characteristic curve ranging from 0.56 to 0.75 (median, 0.73) without chest compressions and from 0.53 to 0.75 (median, 0.69) with compressions ( P<0.001 for difference). Of all measures evaluated, the support vector machine model ranked highest both without chest compressions (area under the receiver operating characteristic curve, 0.75; 95% CI, 0.73-0.78) and with compressions (area under the receiver operating characteristic curve, 0.75; 95% CI, 0.72-0.78; P=0.75 for difference)., Conclusions: VF waveform measures predict functionally-intact survival when calculated during chest compressions, but prognostic performance is generally reduced compared with compression-free analysis. However, support vector machine models exhibited similar performance with and without compressions while also achieving the highest area under the receiver operating characteristic curve. Such machine learning models may, therefore, offer means to guide resuscitation during uninterrupted cardiopulmonary resuscitation.

Objective: Ethnic differences in sudden cardiac arrest resuscitation have not been fully explored and studies have yielded inconsistent results. We examined the association of ethnicity with factors affecting sudden cardiac arrest outcomes., Methods: Retrospective cohort study of 3551 white, 440 black and 297 Asian sudden cardiac arrest cases in Seattle and King County, Washington, USA., Results: Compared with whites, blacks and Asians were younger, had lower socioeconomic status and were more likely to have diabetes, hypertension and end-stage renal disease (all p<0.001). Blacks and Asians were less likely to have a witnessed arrest (whites 57.6%, blacks 52.1%, Asians 46.1%, p<0.001) or receive bystander cardiopulmonary resuscitation (whites 50.9%, blacks 41.4%, Asians 47.1%, p=0.001), but had shorter average emergency medical services response time (mean in minutes: whites 5.18, blacks 4.75, Asians 4.85, p<0.001). Compared with whites, blacks were more likely to be found in pulseless electrical activity (blacks 20.9% vs whites 16.6%, p<0.001), and Asians were more likely to be found in asystole (Asians 41.1% vs whites 30.0%, p<0.001). One of the strongest predictors of resuscitation outcomes was initial cardiac rhythm with 25% of ventricular fibrillation, 4% of patients with pulseless electrical activity and 1% of patients with asystole surviving to hospital discharge (adjusted OR of resuscitation in pulseless electrical activity compared with ventricular fibrillation: 0.30, 95% CI 0.24 to 0.34, p<0.001, adjusted OR of resuscitation in asystole relative to ventricular fibrillation 0.21, 95% CI 0.17 to 0.26, p<0.001). Survival to hospital discharge was similar across all three ethnicities., Conclusions: While there were differences in some prognostic characteristics between blacks, whites and Asians, we did not detect a significant difference in survival following sudden cardiac arrest between the three ethnic groups. There was, however, an ethnic difference in presenting rhythm, with pulseless electrical activity more prevalent in blacks and asystole more prevalent in Asians., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Introduction: Prompt treatment of severe sepsis in the Emergency Department reduces deaths, but the role of prehospital fluid resuscitation is unknown. We sought to determine the risk-adjusted association between prehospital fluid administration and hospital mortality among emergency medical services (EMS) patients admitted with severe sepsis., Methods: We performed a prospective, observational study of patients hospitalized with severe sepsis on admission among 45,394 adult EMS encounters taken to 15 hospitals from 11/2009 to 12/2010 by a two-tier EMS system in King County, Washington. The region mandated recording of prehospital intravenous catheter and fluid administration in prehospital records, along with detailed demographic, incident, physiologic, and hospital adjustment variables. We determined the effect of prehospital intravenous catheter or fluid versus no catheter or fluid on all-cause mortality using multivariable logistic regression., Results: Of all encounters, 1,350 met criteria for severe sepsis on admission, of whom 205 (15%) died by hospital discharge, 312 (23%) received prehospital intravenous fluid, 90 (7%) received a prehospital catheter alone and 948 (70%) did not receive catheter or fluid. EMS administered a median prehospital fluid volume of 500 mL (interquartile range (IQR): 200, 1000 mL). In adjusted models, the administration of any prehospital fluid was associated with reduced hospital mortality (Odds ratio =0.46; 95% Confidence interval: 0.23, 0.88; P =0.02) compared to no prehospital fluid. The odds of hospital mortality were also lower among severe sepsis patients treated with prehospital intravenous catheter alone (Odds ratio =0.3; 95% Confidence interval: 0.17 to 0.57; P <0.01)., Conclusions: In a population-based study, the administration of prehospital fluid and placement of intravenous access were associated with decreased odds of hospital mortality compared with no prehospital catheter or fluid.

Objective: Evidence supports that increasing the balance of "hands-on" CPR may improve survival in ventricular fibrillation out-of-hospital cardiac arrest (OHCA). We assessed whether training and/or AED reconfiguration was associated with an increase in the proportion of time during which CPR was performed between first and second stacks of shocks., Methods: The investigation was a cohort study of 291 persons who suffered ventricular fibrillation OHCA and were treated with at least two stacks of AED shocks by emergency medical services (EMS) first-tier responders. In January 2003, first-tier providers were retrained regarding the importance of CPR. In addition, a subset of AEDs was reconfigured to remove continuous fibrillation detection and its associated voice prompts as to be comparable with other AED models. The amount of time spent on CPR was assessed through review of AED electronic and audio recordings to compare the pre-intervention (n = 241) and post-intervention periods (n = 50)., Results: The proportion of time spent performing hands-on CPR between first and second stacks of shocks was 0.40 in the pre-intervention period compared to 0.51 in the post-intervention period (p = 0.001). The difference was greatest for AEDs where EMS was retrained and the AED reconfigured (0.33 versus 0.50, p = 0.01). No difference in survival was detected between the pre- and post-intervention periods (24.9% versus 28.0%, p = 0.65)., Conclusions: An intervention consisting of retraining and AED reconfiguration was associated with an increase in the proportion of time spent performing CPR between first and second stacks of shocks by first-tier EMS. Whether this increase improves patient outcomes requires additional study.

Introduction: Field information available to emergency medical services (EMS) about a patient’schronic health conditions or medication therapies could help direct patient care or be used toinvestigate outcome disparities. However, little is known about the field availability or accuracy ofinformation of chronic health conditions or chronic medication treatments in emergent circumstances,especially when the patient cannot serve as an information resource. We evaluated the prehospitalavailability and accuracy of specific chronic health conditions and medication treatments among outof-hospital cardiac arrest (OHCA) patients.Methods: The investigation was a retrospective cohort study of adult persons suffering ventricularfibrillation OHCA treated by EMS in a large metropolitan county from January 1, 2007, to December31, 2013. The study was designed to determine the availability and accuracy of EMS ascertainmentof selected chronic health conditions and medication treatments. We evaluated chronic healthconditions of “any heart disease,” congestive heart failure (CHF), and diabetes and medicationtreatments of beta blockers and loop diuretics using two distinct sources: 1) EMS report, and 2)hospital record specific to the OHCA event. Because hospital information was considered the goldstandard, we restricted the primary analysis to those who were admitted to hospital.Results: Of the 1,496 initially eligible patients, 387 could not be resuscitated and were pronounceddead in the field, one patient was left alive at scene due to Physician’s Orders for Life-sustainingTreatment (POLST) orders, 125 expired in the emergency department (n=125), and 983 wereadmitted to hospital. A total of 832 of 1,496 (55.6%) had both sources of data for comparisonand comprised the primary analytic group. Using the hospital record as the gold standard, EMSascertainment had a sensitivity of 0.79 (304/384) and a specificity of 0.88 (218/248) for any priorheart disease; sensitivity 0.45 (47/105) and specificity 0.87 (477/516) for CHF; sensitivity 0.71(143/201) and specificity 0.98 (416/424) for diabetes; sensitivity 0.70 (118/169) and specificity 0.94(273/290) for beta blockers; sensitivity 0.70 (62/89) and specificity 0.97 (358/370) for loop diuretics.Conclusion: In this cohort of OHCA, information about selected chronic health conditions andmedication treatments based on EMS ascertainment was available for many patients, generallyrevealing moderate sensitivity and greater specificity. [West J Emerg Med. 2017;18(5)864-869.]

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Objective: Interruptions in chest compressions during treatment of out-of-hospital cardiac arrest are associated with lower likelihood of successful resuscitation. Real-time automated detection of chest compressions may improve CPR administration during resuscitation, and could facilitate application of next-generation ECG algorithms that employ different parameters depending on compression state. In contrast to accelerometer sensors, transthoracic impedance (TTI) is commonly acquired by defibrillators. We sought to develop and evaluate the performance of a TTI-based algorithm to automatically detect chest compressions. Methods: Five-second TTI segments were collected from patients with out-of-hospital cardiac arrest treated by one of four defibrillator models. Segments with and without chest compressions were collected prior to each of the first four defibrillation shocks (when available) from each case. Patients were divided randomly into 40% training and 60% validation groups. From the training segments, we identified spectral and time-domain features of the TTI associated with compressions. We used logistic regression to predict compression state from these features. Performance was measured by sensitivity and specificity in the validation set. The relationship between performance and TTI segment length was also evaluated. Results: The algorithm was trained using 1859 segments from 460 training patients. Validation sensitivity and specificity were >98% using 2727 segments from 691 validation patients. Validation performance was significantly reduced using segments shorter than 3.2 s. Conclusions: A novel method can reliably detect the presence of chest compressions using TTI. These results suggest potential to provide real-time feedback in order to improve CPR performance or facilitate next-generation ECG rhythm algorithms during resuscitation. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background--Little is known about the long-term survival effects of type-specific bystander cardiopulmonary resuscitation (CPR) in the community. We hypothesized that dispatcher instruction consisting of chest compression alone would be associated with better overall long-term prognosis in comparison with chest compression plus rescue breathing. Methods and Results--The investigation was a retrospective cohort study that combined 2 randomized trials comparing the short-term survival effects of dispatcher CPR instruction consisting either of chest compression alone or chest compression plus rescue breathing. Long-term vital status was ascertained by using the respective National and State death records through July 31, 2011. We performed Kaplan-Meier method and Cox regression to evaluate survival according to the type of CPR instruction. Of the 2496 subjects included in the current investigation, 1243 (50%) were randomly assigned to chest compression alone and 1253 (50%) were randomly assigned to chest compression plus rescue breathing. Baseline characteristics were similar between the 2 CPR groups. During the 1153.2 person-years of follow-up, there were 2260 deaths and 236 long-term survivors. Randomization to chest compression alone in comparison with chest compression plus rescue breathing was associated with a lower risk of death after adjustment for potential confounders (adjusted hazard ratio, 0.91; 95% confidence interval, 0.83-0.99; P=0.02). Conclusions--The findings provide strong support for long-term mortality benefit of dispatcher CPR instruction strategy consisting of chest compression alone rather than chest compression plus rescue breathing among adult patients with cardiac arrest requiring dispatcher assistance. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Little is known about long-term prognosis following resuscitation from out-of-hospital cardiac arrest, especially as it relates to the presenting rhythm or arrest aetiology. We investigated long-term survival among those discharged alive following resuscitation according to presenting rhythm and arrest aetiology. Methods: We conducted a cohort investigation of all non-traumatic adult out-of-hospital cardiac arrest patients resuscitated and discharged alive from hospital between January 1, 2001 and December 31, 2009 in a large metropolitan emergency medical service system. Information about demographics, circumstances, presenting arrest rhythm and aetiology was collected using the dispatch, EMS, and hospital records. Long-term vital status was ascertained using state death records and the Social Security Death Index through 31st December 2010. We used Kaplan Meier to evaluate survival. Results: During the study period, a total of 1001/5958 (17%) persons were resuscitated and discharged alive, of whom 313/1001 (31%) presented with a non-shockable rhythm and 210/1001 (21%) had a non-cardiac aetiology. Overall median survival was 9.8 years with 64% surviving >5 years. Five-year survival was 43% for non-shockable rhythms compared to 73% for shockable rhythms, and 45% for non-cardiac aetiology compared to 69% for cardiac aetiology (p <0.001 respectively). Conclusion: Cardiac arrest due to non-shockable rhythm or non-cardiac aetiology comprises a substantial proportion of those who survive to hospital discharge. Although long-term survival in these groups is less than their shockable or cardiac aetiology counterparts, nearly half are alive 5 years following discharge. The findings support efforts to improve resuscitation care for those with non-shockable rhythms or non-cardiac cause. [Copyright &y& Elsevier]

Objectives: Procainamide is an antiarrhythmic drug of unproven efficacy in cardiac arrest. The association between procainamide and survival from out-of-hospital cardiac arrest was investigated to better determine the drug’s potential role in resuscitation. Methods: The authors conducted a 10-year study of all witnessed, out-of-hospital, ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT) cardiac arrests treated by emergency medical services (EMS) in King County, Washington. Patients were considered eligible for procainamide if they received more than three defibrillation shocks and intravenous (IV) bolus lidocaine. Four logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CI) describing the relationship between procainamide and survival. Results: Of the 665 eligible patients, 176 received procainamide, and 489 did not. On average, procainamide recipients received more shocks and pharmacologic interventions and had lengthier resuscitations. Adjusted for their clinical and resuscitation characteristics, procainamide recipients had a lower likelihood of survival to hospital discharge (OR = 0.52; 95% CI = 0.36 to 0.75). Further adjustment for receipt of other cardiac medications during resuscitation negated this apparent adverse association (OR = 1.02; 95% CI = 0.66 to 1.57). Conclusions: In this observational study of out-of-hospital VF and pulseless VT arrest, procainamide as second-line antiarrhythmic treatment was not associated with survival in models attempting to best account for confounding. The results suggest that procainamide, as administered in this investigation, does not have a large impact on outcome, but cannot eliminate the possibility of a smaller, clinically relevant effect on survival. ACADEMIC EMERGENCY MEDICINE 2010; 17:617–623 © 2010 by the Society for Academic Emergency Medicine [ABSTRACT FROM AUTHOR]

Summary: Background: Measures of the ventricular fibrillation (VF) waveform may enable better allocation of cardiac arrest treatment by discriminating which patients should receive immediate defibrillation versus alternate therapies such as CPR. We derive a new measure based on the ‘roughness’ of the VF waveform, the Logarithm of the Absolute Correlations (LAC), and assess and contrast how well the LAC and the previously published scaling exponent (ScE) predict the duration of VF and the likelihood of return of spontaneous circulation (ROSC) under both optimal experimental and commercial-defibrillator sampling conditions. Methods and results: We derived the LAC and ScE from two different populations–an animal study of 44 swine and a retrospective human sample of 158 out-of-hospital VF arrests treated with a commercial defibrillator. In the animal study, the LAC and ScE were calculated on 5s epochs of VF recorded at 1000samples/s and then down sampled to 125samples/s. In the human study, the LAC and ScE were calculated using 6s epochs recorded at 200samples/s that occurred immediately prior to the initial shock. We compared the LAC and ScE measures using the Spearman correlation coefficients (CC) and areas under the receiver operating characteristic curve (AUC). Results: In the animal study, the LAC and ScE were highly correlated at 1000sample/s (CC=0.93) but not at 125samples/s (CC=−0.06). These correlations were reflected in how well the measures discriminated VF of ≤5 versus >5min: AUC at 1000samples/s was similar for LAC compared to ScE (0.71 versus 0.76). However AUC at 125 samples was greater for LAC compared to ScE (0.75 versus 0.62). In the human study, the LAC measure was a better predictor of ROSC following initial defibrillation as reflected by an AUC of 0.77 for LAC compared to 0.57 for ScE. Conclusions: The LAC is an improvement over the ScE because the LAC retains its prognostic characteristics at lower ECG sampling rates typical of current clinical defibrillators. Hence, the LAC may have a role in better allocating treatment in resuscitation of VF cardiac arrest. [Copyright &y& Elsevier]

This article presents a study that compares the effectiveness of manual chest compression versus the use of an automated chest compression device during the resuscitation of patients following out-of-hospital cardiac arrest. The study examined two sets patients, each treated with a different compression technique, while experiencing a cardiac arrest outside of a hospital setting, in a randomized multi-center trial. The study showed that the use of an automated chest compression device was associated with a higher risk of neurological damage and higher mortality rates than the use of manual chest compression.

The article presents a comparative study from the U.S. regarding the incidence of withholding resuscitations between emergency medical services (EMS) personnel and personnel from other agencies which did not set guidelines for resuscitation. The objective of this study was to determine whether EMS personnel from agencies implementing new guidelines would be more likely to withhold resuscitation from persons having out-of-hospital cardiac arrests.

Background: The importance of the defibrillation waveform on the evolving post-shock cardiac rhythm is uncertain. The primary objective of this study was to evaluate cardiac rhythms following the first defibrillation shock, comparing biphasic truncated exponential (BTE), monophasic damped sinusoidal (MDS), and monophasic truncated exponential (MTE) waveforms in patients experiencing out-of-hospital ventricular fibrillation cardiac arrest (OHCA). Methods: We reviewed the automated external defibrillator (AED) and emergency medical services (EMS) records of 366 patients who suffered OHCA and were treated with defibrillation shocks by first-tier emergency responders between 1 January 1999 and 31 August 2002 in King County, Washington. The post first shock rhythms were determined at 5, 10, 20, 30, and 60 s and compared according to defibrillation waveform. Results: The MDS and BTE waveforms were associated with significantly higher frequency of defibrillation than the MTE waveform, though only the BTE association persisted to 30 and 60 s. No difference in defibrillation rates was detected between MDS and BTE waveforms. By 60 s, an organized rhythm was present in a greater proportion for BTE (40.0%) compared with MDS (25.4%, P=0.01) or MTE (26.5%, P=0.07). Conclusion: In this retrospective cohort investigation, MDS and BTE waveforms had higher first shock defibrillation rates than the MTE waveform, while patients treated with the BTE waveform were more likely to develop an organized rhythm within 60 s of the initial shock. The results of this investigation, however, do not provide evidence that these surrogate advantages are important for improving survival. Additional investigation is needed to improve the understanding of the role of waveform and its potential interaction with other clinical factors in order to optimize survival in OHCA. [Copyright &y& Elsevier]

Evidence has suggested that the pathophysiology of ventricular fibrillation cardiac arrest may consist of 3 time-sensitive phases: electrical, circulatory, and metabolic. We performed a retrospective cohort study of adults in a metropolitan county who had had witnessed ventricular fibrillation arrest before emergency medical services were undertaken to investigate this 3-phase model with regard to bystander cardiopulmonary resuscitation (CPR). We hypothesized that the survival benefit from bystander CPR depends on the collapse-to-shock interval, with the highest benefit occurring during the circulatory phase. The collapse-to-shock interval was a priori grouped into 4 categories: 1 to 5, 6 to 7, 8 to 10, and ≥11 minutes. We used logistic regression analysis to assess whether the association between CPR and survival to hospital discharge depended on the collapse-to-shock interval category. Of the 2,193 events meeting the inclusion criteria, 67.0% had received bystander CPR. The average collapse-to-shock interval was 8.2 ± 2.8 minutes. The survival rate was 33.4%. A higher likelihood of survival was associated with bystander CPR (odds ratio [OR] 1.41, 95% confidence interval [CI] 1.15 to 1.73) and a shorter collapse-to-shock interval (OR −1.84, 95% CI 1.62 to 2.10, for each additional SD of 2.8 minutes less) after adjustment. The beneficial association of CPR increased as the collapse-to-shock interval increased (p = 0.05 for interaction). The bystander CPR was associated with an OR of survival of 0.96 (95% CI 0.64 to 1.46) for a 1- to 5-minute collapse-to shock interval, OR of 1.25 (95% CI 1.00 to 1.58) for a 6- to 7-minute interval, OR of 1.62 (95% CI 1.25 to 2.11) for an 8- to 10-minute interval, and OR of 2.11 (95% CI 1.32 to 3.37) for an ≥11-minute interval. The results of this investigation support a phased model of ventricular fibrillation arrest. The findings suggest that the transition from the electrical to circulatory phase may occur at about 5 minutes, and the circulatory phase may extend to 15 minutes. [Copyright &y& Elsevier]

Background: The objective of this study was to test if caller descriptions of chief complaint delays emergency medical dispatchers' (EMDs) recognition of the need for telephone-assisted CPR (T-CPR).Methods: We conducted an analysis of N = 433 cardiac arrest calls from six large call centers in the United States. Calls were abstracted for initial chief complaint description: caller reports (1) correct medical condition (CMC); (2) incorrect medical condition (IMC), or (3) signs/symptoms only (SS), as well the time interval between call pickup and recognition of the need for T-CPR. In addition, we abstracted if EMDs asked questions related to the caller's chief complaint (rather than, or before), asking about patients' consciousness and breathing status.Results: The majority of cardiac arrest calls (60%) were reported as SS. Median time to recognition of the need for T-CPR was 64 s for SS chief complaints, 47 s for CMC chief complaints, and 100 s for IMC chief complaints. EMDs pursued chief complaint descriptions for 9% of the calls with SS chief complaints, 41% of the calls with IMC chief complaints, and 19% of the calls with CMC chief complaints. Median time to recognition of the need for CPR for calls in which the chief complaint description was pursued was 166 s compared to 62 s for calls in which the chief complaint description was not pursued.Conclusion: Caller chief complaint description affects the time to recognition of the need for T-CPR.Clinical Trial Registration: http://www.clinicaltrials.gov Trial # NCT01972087. [ABSTRACT FROM AUTHOR]

Background: Ventricular fibrillation (VF) waveform measures reflect myocardial physiologic status. Continuous assessment of VF prognosis using such measures could guide resuscitation, but has not been possible due to CPR artifact in the ECG. A recently-validated VF measure (termed VitalityScore), which estimates the probability (0-100%) of return-of-rhythm (ROR) after shock, can assess VF during CPR, suggesting potential for continuous application during resuscitation.Objective: We evaluated VF using VitalityScore to characterize VF prognostic status continuously during resuscitation.Methods: We characterized VF using VitalityScore during 60 seconds of CPR and 10 seconds of subsequent pre-shock CPR interruption in patients with out-of-hospital VF arrest. VitalityScore utility was quantified using area under the receiver operating characteristic curve (AUC). VitalityScore trends over time were estimated using mixed-effects models, and associations between trends and ROR were evaluated using logistic models. A sensitivity analysis characterized VF during protracted (100-second) periods of CPR.Results: We evaluated 724 VF episodes among 434 patients. After an initial decline from 0-8 seconds following VF onset, VitalityScore increased slightly during CPR from 8-60 seconds (slope: 0.18%/min). During the first 10 seconds of subsequent pre-shock CPR interruption, VitalityScore declined (slope: -14%/min). VitalityScore predicted ROR throughout CPR with AUCs 0.73-0.75. Individual VitalityScore trends during 8-60 seconds of CPR were marginally associated with subsequent ROR (adjusted odds ratio for interquartile slope change (OR) = 1.10, p = 0.21), and became significant with protracted (100 seconds) CPR duration (OR = 1.28, p = 0.006).Conclusion: VF prognostic status can be continuously evaluated during resuscitation, a development that could translate to patient-specific resuscitation strategies. [ABSTRACT FROM AUTHOR]

Abstract: Background: Resuscitation centers may improve patient outcomes by achieving sufficient experience in post-resuscitation care. We analyzed the relationship between survival and hospital volume among patients suffering out-of-hospital cardiac arrest (OHCA). Methods: This prospective cohort investigation collected data from the Cardiac Arrest Registry to Enhance Survival database from 10/1/05 to 12/31/09. Primary outcome was survival to discharge. Hospital characteristics were obtained via 2005 American Hospital Association Survey. A hospital''s use of hypothermia was obtained via direct survey. To adjust for hospital- and patient-level variation, multilevel, hierarchical logistic regression was performed. Hospital volume was modeled as a categorical (OHCA/year≤10, 11–39, ≥40) variable. A stratified analysis evaluating those with ventricular fibrillation or pulseless ventricular tachycardia (VF/VT) was also performed. Results: The cohort included 4125 patients transported by EMS to 155 hospitals in 16 states. Overall survival to hospital discharge was 35% among those admitted to the hospital. Individual hospital rates of survival varied widely (0–100%). Unadjusted survival did not differ between the 3 hospital groups (36% for ≤10 OHCA/year, 35% for 11–39, and 36% for ≥40; p =0.75). After multilevel adjustment, differences in survival across the groups were not statistically significant. Compared to patients at hospitals with ≤10 OHCA/year, adjusted OR for survival was 1.04 (CI95 0.83–1.28) among 11–39 annual volume and 0.97 (CI95 0.73–1.30) among the ≥40 volume hospitals. Among patients presenting with VF/VT, no difference in survival was identified between the hospital groups. Conclusion: Survival varied substantially across hospitals. However, hospital OHCA volume was not associated with likelihood of survival. Additional efforts are required to determine what hospital characteristics might account for the variability observed in OHCA hospital outcomes. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

Background Out-of-hospital cardiac arrest (OHCA) remains a leading cause of death and a 2010 meta-analysis concluded that outcomes have not improved over several decades. However, guidelines have changed to emphasize CPR quality, minimization of interruptions, and standardized post-resuscitation care. We sought to evaluate whether OHCA outcomes have improved over time among agencies participating in the Resuscitation Outcomes Consortium (ROC) cardiac arrest registry (Epistry) and randomized clinical trials (RCTs). Methods Observational cohort study of 47,148 EMS-treated OHCA cases in Epistry from 139 EMS agencies at 10 ROC sites that participated in at least one RCT between 1/1/2006 and 12/31/2010. We reviewed patient, scene, event characteristics, and outcomes of EMS-treated OHCA over time, including subgroups with initial rhythm of pulseless ventricular tachycardia or ventricular fibrillation (VT/VF). Results Mean response interval, median age and male proportion remained similar over time. Unadjusted survival to discharge increased between 2006 and 2010 for treated OHCA (from 8.2% to 10.4%), as well as for subgroups of VT/VF (21.4% to 29.3%) and bystander witnessed VT/VF (23.5% to 30.3%). Compared with 2006, adjusted survival to discharge was significantly higher in 2010 for treated cases (OR = 1.72; 95% CI 1.53, 1.94), VT/VF cases (OR = 1.69; 95% CI 1.45, 1.98) and bystander witnessed VT/VF cases (OR = 1.65; 95% CI 1.36, 2.00). Tests for trend in each subgroup were significant ( p < 0.001). Conclusions ROC-wide survival increased significantly between 2006 and 2010. Additional research efforts are warranted to identify specific factors associated with this improvement. [ABSTRACT FROM AUTHOR]

Objective The accuracy of methods that classify the cardiac rhythm despite CPR artifact could potentially be improved by utilizing continuous ECG data. Our objective is to compare three approaches which use identical ECG features and differ only in their degree of temporal integration: (1) static classification, which analyzes 4-s ECG frames in isolation; (2) “best-of-three averaging,” which takes the average of three consecutive static classifications successively; and (3) “adaptive rhythm sequencing,” which uses hidden Markov models to model ECG segments as rhythm sequences. Methods Defibrillator recordings from 95 out-of-hospital cardiac arrests were divided into training and test sets. Each method classified the rhythm as asystole, organized rhythm or shockable rhythm throughout the recordings. Classifications were compared to the gold standard of physician review. The primary outcome was accuracy during CPR, which was estimated using a generalized linear mixed-effects model. Results In the training set, accuracies during CPR were 0.89 (95% CI 0.85, 0.92), 0.92 (95% CI 0.89, 0.94) and 0.97 (95% CI 0.95, 0.98) for the static, best-of-three averaging and adaptive rhythm sequencing methods, respectively. The corresponding results in the test set were 0.92 (95% CI 0.86, 0.96), 0.94 (95% CI 0.89, 0.97), and 0.97 (95% CI 0.94, 0.99). Of the dynamic methods, only adaptive rhythm sequencing was significantly more accurate than static classification in the training ( p < 0.001) and test ( p = 0.03) sets. Conclusion In a continuous monitoring setting, adaptive rhythm sequencing was significantly more accurate than static rhythm classification during CPR. [ABSTRACT FROM AUTHOR]

The article focuses on the increase of the low bystander cardiopulmonary resuscitation (CPR) provision in communities. The four steps to provide bystander CPR include the recognition of the assistance needed by the victim, calling the 9-1-1, and identification the occurrence of cardiac arrest. Moreover, standardized metrics at the community is needed for the accuracy of the evaluation of the effectiveness of community-based CPR programs.

Background--Out-of-hospital cardiac arrest (OHCA) claims millions of lives worldwide each year. OHCA survival from shockable arrhythmias (ventricular fibrillation/tachycardia) improved in several communities after implementation of American Heart Association resuscitation guidelines that eliminated "stacked" shocks and emphasized chest compressions. "Nonshockable" rhythms are now the predominant presentation of OHCA; the benefit of such treatments on nonshockable rhythms is uncertain. Methods and Results--We studied 3960 patients with nontraumatic OHCA from nonshockable initial rhythms treated by prehospital providers in King County, Washington, over a 10-year period. Outcomes during a 5-year intervention period after adoption of new resuscitation guidelines were compared with the previous 5-year historical control period. The primary outcome was 1-year survival. Patient demographics and resuscitation characteristics were similar between the control (n=1774) and intervention (n = 2186) groups, among whom 471 of 1774 patients (27%) versus 742 of 2186 patients (34%), respectively, achieved return of spontaneous circulation; 82 (4.6%) versus 149 (6.8%) were discharged from hospital, 60 (3.4%) versus 112 (5.1%) with favorable neurological outcome; 73 (4.1%) versus 135 (6.2%) survived 1 month; and 48 (2.7%) versus 106 patients (4.9%) survived 1 year (all P≤O.005). After adjustment for potential confounders, the intervention period was associated with an improved odds of 1.50 (95% confidence interval, 1.29-1.74) for return of spontaneous circulation, 1.53 (95% confidence interval, 1.14-2.05) for hospital survival, 1.56 (95% confidence interval, 1.11-2.18) for favorable neurological status, 1.54 (95% confidence interval, 1.14-2.10) for 1-month survival, and 1.85 (95% confidence interval, 1.29-2.66) for 1-year survival. Conclusion--Outcomes from OHCA resulting from nonshockable rhythms, although poor by comparison with shockable rhythm presentations, improved significantly after implementation of resuscitation guideline changes, suggesting their potential to benefit all presentations of OHCA. [ABSTRACT FROM AUTHOR]

Introduction: The act of conducting a research study could potentially improve quality of care by focusing providers on the study condition or detract from care by distracting providers with complex protocols. We hypothesized that odds of receiving bystander cardiopulmonary resuscitation (CPR) would be higher during a trial of dispatcher-assisted CPR instructions than during periods immediately before and after. Methods: The investigation was a cohort study of 8,626 adult subjects who suffered non-traumatic out-of-hospital cardiac arrest prior to emergency medical services (EMS) arrival in greater King County, Washington, between January 1, 1999, and December 31, 2011. Bystander CPR status was assessed through review of audio dispatch tapes and EMS reports to classify any bystander CPR (any B-CPR). Any B-CPR was further categorized as bystander CPR with dispatcher assistance (DA-CPR) or bystander CPR without dispatcher assistance (B-CPR, no DA). We used multivariable logistic regression to evaluate the odds of any B-CPR before, during, and after the Dispatcher Assisted Resuscitation Trial (DART), a randomized trial of dispatcher-assisted CPR instruction comparing chest compressions alone with compressions plus rescue breaths, which ran from June 1, 2004, to September 30, 2009. We also evaluated whether the odds varied by type-specific B-CPR. Results: Patient and arrest circumstances were similar across the study periods. Compared to the period before DART, odds of receiving any B-CPR were higher during DART (OR=1.35, 95% CI = 1.23-1.49), but no different after OR=1.11, 0.98-1.25). Similarly, compared to the before period, the odds of DA-CPR were higher during DART (OR=1.79, 1.59-2.02) but no different after (OR=0.94, 0.80-1.10) (Table 1). Discussion: Odds of bystander CPR were higher during the study compared to periods before and after. The increase seems to be largely related to higher likelihood of DA-CPR, suggesting a possible community-wide benefit from this research protocol. [ABSTRACT FROM AUTHOR]