Introduction: There is no standard for categorizing reasons for death in those who achieve return of spontaneous circulation (ROSC) after cardiac arrest but die before hospital discharge. Categorization is important for comparing outcomes across studies, assessing benefits of interventions, and developing quality-improvement initiatives. We developed and tested a method for categorizing reasons for death after cardiac arrest in both in-hospital (IHCA) and out-ofhospital (OHCA) arrests. Methods: Single-center, retrospective, cohort study of patients with ROSC after IHCA or OHCA between 2008 and 2017 who died before hospital discharge. Traumatic arrests and patients with

Background-While survival after in-hospital cardiac arrest (IHCA) has improved in recent years, it remains unknown whether this trend primarily applies to younger IHCA victims. The aim of this study was to assess trends in survival to hospital discharge after adult IHCA across age groups from 2000 to 2016.Methods-This is an observational study of IHCA patients included in the Get With The Guidelines®-Resuscitation registry between 2000 and 2016. The primary outcome was survival to hospital discharge. Patients were stratified into five age groups: <50 years, 50-59 years, 60-69 years, 70-79 years, and ≥80 years. Generalized linear regression was used to obtain absolute survival rates over time.Results-A total of 234,767 IHCA patients were included. The absolute increase in survival per calendar year was 0.8% (95% CI 0.7-1.0%, p <0.001) for patients younger than 50 years, 0.6% (95% CI 0.4-0.7%, p <0.001) for patients between 50 and 59 years, 0.5% (95% CI 0.4-0.6%, p <0.001) for patients between 60 and 69 years, 0.5% (95% CI 0.4-0.6%, p <0.001) for patients between 70 and 79 years, and 0.5% (95% CI 0.4-0.6%, p <0.001) for patients older than 80 years.

Introduction: Atropine was removed from the 2010 American Heart Association’s Advanced Cardiac Life Support guidelines as routine management of non-shockable cardiac arrest, although the evidence to support or refute the use of atropine is lacking. In a previous study, atropine usage was shown to subsequently decline markedly. Whether removing atropine from the guidelines has affected survival remains unknown. Methods: Using the Get With The Guidelines®-Resuscitation registry, we included adult patients with an index in-hospital cardiac arrest between 2006-2015. Non-shockable and shockable cardiac arrest patients with high vs. low propensity score to receive atropine were separated into two cohorts. An interrupted time-series analysis was used to compare survival before (pre-exposure) and after (post-exposure) introduction of the 2010 guidelines. A difference-in-difference approach was used to compare the interrupted time-series results between the non-shockable and shockable cohorts to account for guideline changes unrelated to atropine. Results: We included 21,822 non-shockable and 4,268 shockable cardiac arrests. Patient characteristics were similar between the pre-exposure and post-exposure period. Atropine was used for 9,170 (86%) non-shockable and 733 (34%) shockable cardiac arrests in the pre-exposure period and 3,903 (35%) non-shockable and 339 (16%) shockable cardiac arrests in the post-exposure period. The change over time in survival from the pre-exposure to the post-exposure period was not significantly different for the non-shockable compared to the shockable cohort (mean difference: 2.0% [95%CI: -0.7, 4.6] per year, p = 0.15, Figure). The immediate change in survival after introducing the guidelines was also not different between the cohorts (mean difference: 3.9% [95%CI: -2.2, 10], p = 0.21, Figure). Conclusions: The removal of atropine from the 2010 guidelines was not associated with a change in survival in our analysis.

Background: While survival after in-hospital cardiac arrest (IHCA) has improved in recent years, it remains unknown whether this trend primarily applies to younger IHCA victims or extends to older patients as well. The aim of this study was to assess trends in survival to hospital discharge after adult IHCA across age groups from 2000 to 2016. Methods: This is an observational study of IHCA patients included in the Get With The Guidelines®-Resuscitation registry between January 2000 and December 2016. The primary outcome was survival to hospital discharge, while secondary outcomes included rates of return of spontaneous circulation (ROSC) and neurological outcome at discharge. Patients were stratified into five age groups: < 50 years, 50-59 years, 60-69 years, 70-79 years, and ≥80 years. Generalized linear regression was used to obtain absolute survival rates over time. Analyses of interaction were included to assess differences in survival trends between age groups. Results: A total of 234,767 IHCA patients were included for the analyses. The absolute increase in survival per calendar year was 0.8% (95%CI 0.7 - 1.0%, p < 0.001) for patients younger than 50 years, 0.6% (95%CI 0.4 - 0.7%, p < 0.001) for patients between 50 and 59 years, 0.5% (95%CI 0.4 - 0.6%, p < 0.001) for patients between 60 and 69 years, 0.5% (95%CI 0.4 - 0.6%, p < 0.001) for patients between 70 and 79 years, and 0.5% (95%CI 0.4 - 0.6%, p < 0.001) for patients older than 80 years. Further, a significant increase in both rates of ROSC and survival with a good neurological outcome was seen for all age groups. In both unadjusted and adjusted analyses of survival, we observed a significant interaction between calendar year and age group ( p < 0.001), indicating that the rate of improvement in survival over time was significantly different between age groups. Conclusions: For patients with IHCA, survival to discharge, ROSC, and survival to discharge with a good neurological outcome have improved significantly from 2000 to 2016 for all age groups.

Introduction: There is no standard method for reporting reasons for death in cardiac arrest patients. Categorizing reasons for death is important for comparing outcomes across cardiac arrest trials, assessing the benefits of targeted interventions in in-hospital (IHCA) and out-of-hospital (OHCA) cardiac arrest patients, and developing quality-improvement initiatives. We developed and tested a method for categorizing reasons for death in post-cardiac arrest patients, assessed inter-rater reliability, and compared reasons for death between IHCA and OHCA. Methods: Single-center, retrospective, cohort study of patients who had return of spontaneous circulation (ROSC) after an OHCA or IHCA between 2008 and 2017, but died before hospital discharge. Traumatic arrests and patients with a “do-not-resuscitate” order prior to their initial arrest were excluded. Two independent investigators reviewed medical records and assigned each patient to one of five predefined categories of reasons for death. Inter-rater reliability was assessed using Fleiss Kappa. For final categorization, discrepancies were resolved by discussion with a third investigator. Categorical data was compared by Fisher’s Exact Test, and continuous data by Wilcoxon Rank-Sum Test. Results: There were 182 IHCA and 227 OHCA included, with the initial rhythm being non-shockable in 77% and 69% of cases (p=0.07), respectively. Median time to ROSC was shorter in IHCA compared to OHCA (10 [IQR: 6-20] vs 30 [IQR: 21-42] min, p<0.01). Median time to death was 3.3 (IQR: 1.4-8.7) days in IHCA vs 3.5 (IQR: 1.8-5.9) days in OHCA (p=0.92). The Kappa for reasons for death was 0.62 for IHCA and 0.61 for OHCA. Reasons for death for IHCA and OHCA were: neurological withdrawal of care (28% vs 72%, p<0.01), comorbid withdrawal of care (36% vs 4%, p<0.01), refractory hemodynamic shock 24% vs 18%, p=0.11), respiratory failure (1% vs 2%, p=0.47), and sudden cardiac death (11% vs 4%, p<0.01). Conclusion: Five categories for reasons for death in post-cardiac arrest patients were developed. The primary reason for death was neurological withdrawal of care after OHCA and comorbid withdrawal of care after IHCA. Categorizing reasons for death may be important for investigators when targeting an IHCA vs an OHCA population.

Aim-To determine whether the removal of atropine from the 2010 ACLS guidelines for nonshockable cardiac arrests was associated with a change in survival. Methods-Using the Get With The Guidelines®-Resuscitation registry, we included adults with an index in-hospital cardiac arrest between 2006 and 2015. The primary outcome was survival to hospital discharge. Secondary outcomes included return of spontaneous circulation and favorable functional outcome. An interrupted time-series analysis was used to compare survival before (preguidelines) and after (post-guidelines) introduction of the 2010 guidelines. A difference-in-* The members of the Get With The Guidelines®-Resuscitation Adult Research Task Force are listed at the end of the article