Trend analysis of disability-adjusted life years following adult out-of-hospital cardiac arrest in the United States: A study from the CARES Surveillance Group

Performance of the MRI lesion pattern score in predicting neurological outcome after out of hospital cardiac arrest: a retrospective cohort analysis

BACKGROUND

Despite advances in resuscitation practice, patient survival following cardiac arrest remains poor. The utilization of MRI in neurological outcome prognostication post-cardiac arrest is growing and various classifications has been proposed; however a consensus has yet to be established. MRI, though valuable, is resource-intensive, time-consuming, costly, and not universally available. This study aims to validate a MRI lesion pattern score in a cohort of out of hospital cardiac arrest patients at a tertiary referral hospital in Switzerland.

METHODS

This cohort study spanned twelve months from February 2021 to January 2022, encompassing all unconscious patients aged ≥ 18 years who experienced out-of-hospital cardiac arrest of any cause and were admitted to the intensive care unit (ICU) at Inselspital, University Hospital Bern, Switzerland. We included patients who underwent the neuroprognostication process, assessing the performance and validation of a MRI scoring system.

RESULTS

Over the twelve-month period, 137 patients were admitted to the ICU, with 52 entering the neuroprognostication process and 47 undergoing MRI analysis. Among the 35 MRIs indicating severe hypoxic brain injury, 33 patients (94%) experienced an unfavourable outcome (UO), while ten (83%) of the twelve patients with no or minimal MRI lesions had a favourable outcome. This yielded a sensitivity of 0.94 and specificity of 0.83 for predicting UO with the proposed MRI scoring system. The positive and negative likelihood ratios were 5.53 and 0.07, respectively, resulting in an accuracy of 91.49%.

CONCLUSION

We demonstrated the effectiveness of the MLP scoring scheme in predicting neurological outcome in patients following cardiac arrest. However, to ensure a comprehensive neuroprognostication, MRI results need to be combined with other assessments. While neuroimaging is a promising objective tool for neuroprognostication, given the absence of sedation-related confounders-compared to electroencephalogram (EEG) and clinical examination-the current lack of a validated scoring system necessitates further studies. Incorporating standardized MRI techniques and grading systems is crucial for advancing the reliability of neuroimaging for neuroprognostication.

TRIAL REGISTRATION

Registry of all Projects in Switzerland (RAPS) 2020-01761.

Cardioprotection by Poloxamer 188 is Mediated through Increased Endothelial Nitric Oxide Production

Ischemia/reperfusion (I/R) injury significantly contributes to the morbidity and mortality associated with cardiac events. Poloxamer 188 (P188), a nonionic triblock copolymer, has been proposed to mitigate I/R injury by stabilizing cell membranes. However, the underlying mechanisms remain incompletely understood, particularly concerning endothelial cell function and nitric oxide (NO) production. We employed human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (CMs) and endothelial cells (ECs) to elucidate the effects of P188 on cellular survival, function, and NO secretion under simulated I/R conditions. iPSC-CMs contractility and iPSC-ECs' NO production were assessed following exposure to P188. Further, an isolated heart model using Brown Norway rats subjected to I/R injury was utilized to evaluate the ex-vivo cardioprotective effects of P188, examining cardiac function and NO production, with and without the administration of a NO inhibitor. In iPSC-derived models, P188 significantly preserved CM contractile function and enhanced cell viability after hypoxia/reoxygenation. Remarkably, P188 treatment led to a pronounced increase in NO secretion in iPSC-ECs, a novel finding demonstrating endothelial protective effects beyond membrane stabilization. In the rat isolated heart model, administration of P188 during reperfusion notably improved cardiac function and reduced I/R injury markers. This cardioprotective effect was abrogated by NO inhibition, underscoring the pivotal role of NO. Additionally, a dose-dependent increase in NO production was observed in non-ischemic rat hearts treated with P188, further establishing the critical function of NO in P188 induced cardioprotection. In conclusion, our comprehensive study unveils a novel role of NO in mediating the protective effects of P188 against I/R injury. This mechanism is evident in both cellular models and intact rat hearts, highlighting the potential of P188 as a therapeutic agent against I/R injury. Our findings pave the way for further investigation into P188's therapeutic mechanisms and its potential application in clinical settings to mitigate I/R-related cardiac dysfunction.

The Public Health and Economic Impact of Drug Overdose Out-of-Hospital Cardiac Arrest in the United States

OBJECTIVE

To calculate disability-adjusted life years (DALY) and labor productivity loss due to drug overdose out-of-hospital cardiac arrest (DO-OHCA) and compare its contribution to the burden of disease and economic impact of all-cause nontraumatic out-of-hospital cardiac arrest (OHCA) in the US.

METHODS

We performed a retrospective observational cohort analysis of all adult (age ≥18 years) nontraumatic emergency medical services-treated OHCA events, including those due to DO-OHCA, from the national Cardiac Arrest Registry to Enhance Survival (CARES) database from January 1, 2017 and December 31, 2020. The main outcome measures of interest were disability-adjusted life years, annual, and lifetime labor productivity loss over the 4-year study period. The findings for the study population were extrapolated to a national level using the CARES population catchment and U.S. population estimates by year.

RESULTS

A total of 378,088 adult OHCA events, including 23,252 DO-OHCA (6.2%) met study inclusion criteria. The DO-OHCA DALY increased from 156,707 in 2017 to 265,692 in 2020. Per year, DO-OHCA contributed to 11.4%, 12.0%, 10.5%, and 11.4% of all OHCA DALY lost from 2017-2020, respectively. The mean annual and lifetime productivity losses for all OHCA were stable over time (annual: $47K in 2017 to $50K in 2020; lifetime: $647K in 2017 to $692K in 2020). The CARES population catchment increased by 39.8% over the study period (102.6 M in 2017 to 143.4 M in 2020). For DO-OHCA, the mean annual productivity loss was approximately 30% higher than non-DO-OHCA ($64K vs. $49K in 2020, respectively). The mean lifetime productivity loss for DO-OHCA was 2.5 times higher than non-DO-OHCA ($1.6 M vs. $630K in 2020, respectively).

CONCLUSIONS

The DALY due to DO-OHCA has increased over time with expansion of the CARES dataset, but its relative contribution to total OHCA DALY (all non-traumatic etiologies) remained fairly stable. The DO-OHCAs represent approximately 6% of all adult non-traumatic EMS-treated OHCA events but has a disproportionately greater economic impact. Continued efforts to reduce DO-OHCA through public health initiatives are warranted to lessen the societal impact of OHCA in the U.S.

Incidence and Long-Term Outcomes of Acute Myocardial Infarction Among Survivors of Out-of-Hospital Cardiac Arrest

BACKGROUND

Despite the increasing long-term survival after out-of-hospital cardiac arrest (OHCA), the risk of subsequent acute myocardial infarction (AMI) remains poorly understood. We aimed to determine the incidence, predictors, and long-term outcomes of AMI among survivors of OHCA.

METHODS AND RESULTS

We assembled a retrospective cohort of 882 patients with OHCA who survived to 30 days or discharge from the hospital between 2010 and 2019. Survivors of OHCA had an increased risk of subsequent AMI, defined as AMI occurring 30 days after index OHCA or following discharge from the hospital after OHCA, compared with the general population when matched for age and sex (standardized incidence ratio, 4.64 [95% CI, 3.52-6.01]). Age-specific risks of subsequent AMI for men (standardized incidence ratio, 3.29 [95% CI, 2.39-4.42]) and women (standardized incidence ratio, 6.15 [95% CI, 3.27-10.52]) were significantly increased. A total of 7.2%, 8.3%, and 14.3% of survivors of OHCA had a subsequent AMI at 3 years, 5 years, and end of follow-up, respectively. Age at OHCA (hazard ratio [HR], 1.04 [95% CI, 1.02-1.06]) and past medical history of prior AMI, defined as any AMI preceding or during the index OHCA event (HR, 1.84 [95% CI, 1.05-3.22]), were associated with subsequent AMI, while an initial shockable rhythm was not (HR, 1.00 [95% CI, 0.52-1.94]). Survivors of OHCA with subsequent AMI had a higher risk of death (HR, 1.58 [95% CI, 1.12-2.22]) than those without.

CONCLUSIONS

Survivors of OHCA are at an increased risk of subsequent AMI compared with the general population. Prior AMI, but not an initial shockable rhythm, increases this risk, while subsequent AMI predicts death. Preventive measures for AMI including cardiovascular risk factor control and revascularization may thus improve outcomes in selected patients with cardiac pathogenesis.

Disability-Adjusted Life-Years After Adult In-Hospital Cardiac Arrest in the United States

We sought to estimate disability-adjusted life-years (DALYs) because of adult in-hospital cardiac arrest (IHCA) and to compare IHCA DALY to other leading causes of death and disability in the United States. DALY were calculated as the sum of years of life lost and years lived with disability. The years of life lost were calculated using all adult IHCA with complete data from the American Heart Association Get With The Guidelines-Resuscitation database for 2015 to 2019. Cerebral performance category scores and published disability weights were used to estimate the years lived with disability for survivors. The cohort's DALY were extrapolated to a national level to estimate the total United States DALY and were compared with a published ranking of the leading causes of DALY in the United States for 2018. Data were reported as DALY total and rate per 100,000. A total of 99,897 IHCA were included from 329 hospitals. The total IHCA DALY increased from 2,208,310 in 2015 to 2,225,722 in 2019. A modest decrease in the DALY rate was observed from 689 per 100,000 in 2015 to 678 per 100,000 in 2019. In 2018, the rate of IHCA DALY were 728 per 100,000, which represented the 11th leading cause of DALY. When combined with out-of-hospital cardiac arrest (1,322 per 100,000), sudden cardiac arrest (2,050 per 100,000) was found the be the 2nd leading cause of DALY after ischemic heart disease (2,681 per 100,000) in 2018. In conclusion, adult IHCA is a leading cause of DALY in the United States and has increased over time because of the expansion of the Get With The Guidelines-Resuscitation database.

Disability-Adjusted Life Years Due to Pediatric Out-of-Hospital Cardiac Arrest in the United States: A CARES Surveillance Group Study

BACKGROUND

Disability-adjusted life years (DALY) are a common public health metric used to estimate disease burden. The DALY due to pediatric out-of-hospital cardiac arrest (OHCA) in the United States is unknown. We aimed to estimate pediatric OHCA DALY and to compare it with the other leading causes of pediatric death and disability in the United States.

METHODS

We conducted a retrospective observational analysis of the national Cardiac Arrest Registry to Enhance Survival database. DALY were calculated as the sum of years of life lost and years lived with disability. Years of life lost were calculated using all pediatric (age <18 years) nontraumatic OHCA from the Cardiac Arrest Registry to Enhance Survival from 2016 to 2020. Disability weights based on cerebral performance category scores, an outcome measure of neurologic function, were used to estimate years lived with disability . Data were reported as total, mean, and rate per 100 000 individuals, and were compared with the leading causes of pediatric DALY in the United States published by the Global Burden of Disease study for 2019.

RESULTS

Totally 11 177 OHCA met the study inclusion criteria. A modest increase in total OHCA DALY in the United States was observed from 407 500 (years of life lost = 407 435 and years lived with disability =65) in 2016 to 415 113 (years of life lost = 415 055 and years lived with disability =58) in 2020. The DALY rate increased from 553.3 per 100 000 individuals in 2016 to 568.3 per 100 000 individuals in 2020. For 2019, OHCA was the 10th leading cause of pediatric DALY lost behind neonatal disorders, injuries, mental disorders, premature birth, musculoskeletal disorders, congenital birth defects, skin diseases, chronic respiratory diseases, and asthma.

CONCLUSIONS

Nontraumatic OHCA is one of the top 10 leading causes of annual pediatric DALY lost in the United States.

Implementation of a regional extracorporeal membrane oxygenation program for refractory ventricular fibrillation out-of-hospital cardiac arrest

BACKGROUND

eCPR, the modality of extracorporeal membrane oxygenation (ECMO) applied in the setting of cardiac arrest, has emerged as a novel therapy which may improve outcomes in select patients with out-of-hospital cardiac arrest (OHCA). To date, implementation has been mainly limited to single academic centres. Our objective is to describe the feasibility and challenges with implementation of a regional protocol for eCPR.

METHODS

The Los Angeles County Emergency Medical Services (EMS) Agency implemented a regional eCPR protocol in July 2020, which included coordination across multiple EMS provider agencies and hospitals to route patients with refractory ventricular fibrillation (rVF) OHCA to eCPR-capable centres (ECCs). Data were entered on consecutive patients with rVF with suspected cardiac aetiology into a centralized database including time intervals, field and in-hospital care, survival and neurologic outcome.

RESULTS

From July 27, 2020 through July 31, 2022, 35 patients (median age 57 years, 6 (17%) female) were routed to ECCs, of whom 11 (31%) received eCPR and 3 (27%) treated with eCPR survived, all of whom had a full neurologic recovery. Challenges encountered during implementation included cost to EMS provider agencies for training, implementation, and purchase of automatic chest compression devices, maintenance of system awareness, hospital administrative support for staffing and equipment for the ECMO program, and interdepartmental coordination at ECCs.

CONCLUSION

We describe the successful implementation of a regional eCPR program with ongoing patient enrolment and data collection. These preliminary findings can serve as a model for other EMS systems who seek to implement regional eCPR programs.

Does One Size Fit All? External Validation of the rCAST Score to Predict the Hospital Outcomes of Post-Cardiac Arrest Patients Receiving Targeted Temperature Management

The revised post-Cardiac Arrest Syndrome for Therapeutic hypothermia (rCAST) score was proposed to predict neurologic outcomes and mortality among out-of-hospital cardiac arrest (OHCA) patients. However, it has rarely been validated outside Japan. Therefore, this study aimed to investigate this issue. All adult patients admitted to our medical intensive care unit for targeted temperature management (TTM) between July 2015 and July 2021 were enrolled. Their medical records were retrieved, and rCAST scores were calculated. A total of 108 post-cardiac arrest syndrome (PCAS) patients who received TTM were analyzed. According to the rCAST score, 49.1%, 50.0%, and 0.9% of the patients were classified as low, moderate, and high severity, respectively. The areas under the curves for the rCAST score were 0.806 (95% confidence interval [CI]: 0.719-0.876) and 0.794 (95% CI: 0.706-0.866) to predict poor neurologic outcomes and mortality at day 28, respectively. In contrast to the original report, only low-severity patients had favorable neurologic outcomes. The rCAST score showed moderate accuracy in our OHCA patients with PCAS who received TTM to predict poor neurologic outcomes and mortality at day 28.

Long term survival and disease burden from out-of-hospital cardiac arrest in Singapore: a population-based cohort study

Background

Understanding the long-term outcomes and disability-adjusted life years (DALY) after out-of-hospital cardiac arrest (OHCA) is important to understand the overall health and disease burden of OHCA respectively, but data in Asia remains limited. We aimed to quantify long-term survival and the annual disease burden of OHCA within a national multi-ethnic Asian cohort.

Methods

We conducted an open cohort study linking the Singapore Pan-Asian Resuscitation Outcomes Study (PAROS) and the Singapore Registry of Births and Deaths from 2010 to 2019. We performed Cox regression, constructed Kaplan-Meier curves, and calculated DALYs and standardised mortality ratios (SMR) for each year of follow-up.

Results

We analysed 802 cases. The mean age was 56.0 (SD 17.8). Most were male (631 cases, 78,7%) and of Chinese ethnicity (552 cases, 68.8%). At one year, the SMR was 14.9 (95% CI:12.5-17.8), decreasing to 1.2 (95% CI:0.7-1.8) at three years, and 0.4 (95% CI:0.2-0.8) at five years. Age at arrest (HR:1.03, 95% CI:1.02-1.04, p < 0.001), shockable presenting rhythm (HR:0.75, 95% CI:0.52-0.93, p = 0.015) and CPC category (HR:4.62, 95% CI:3.17-6.75, p < 0.001) were independently associated with mortality. Annual DALYs due to OHCA varied from 304.1 in 2010 to 849.7 in 2015, then 547.1 in 2018. Mean DALYs decreased from 12.162 in 2010 to 3.599 in 2018.

Conclusions

OHCA survivors had an increased mortality rate for the first three years which subsequently normalised compared to that of the general population. Annual OHCA disease burden in DALY trended downwards from 2010 to 2018. Improved surveillance and OHCA treatment strategies may improve long-term survivorship and decrease its global burden.

Funding

National Medical Research Council, Singapore, under the Clinician Scientist Award (NMRC/CSA-SI/0014/2017) and the Singapore Translational Research Investigator Award (MOH-000982-01).

Repetitive Electroencephalography as Biomarker for the Prediction of Survival in Patients with Post-Hypoxic Encephalopathy

Predicting survival in patients with post-hypoxic encephalopathy (HE) after cardiopulmonary resuscitation is a challenging aspect of modern neurocritical care. Here, continuous electroencephalography (cEEG) has been established as the gold standard for neurophysiological outcome prediction. Unfortunately, cEEG is not comprehensively available, especially in rural regions and developing countries. The objective of this monocentric study was to investigate the predictive properties of repetitive EEGs (rEEGs) with respect to 12-month survival based on data for 199 adult patients with HE, using log-rank and multivariate Cox regression analysis (MCRA). A total number of 59 patients (29.6%) received more than one EEG during the first 14 days of acute neurocritical care. These patients were analyzed for the presence of and changes in specific EEG patterns that have been shown to be associated with favorable or poor outcomes in HE. Based on MCRA, an initially normal amplitude with secondary low-voltage EEG remained as the only significant predictor for an unfavorable outcome, whereas all other relevant parameters identified by univariate analysis remained non-significant in the model. In conclusion, rEEG during early neurocritical care may help to assess the prognosis of HE patients if cEEG is not available.

Estimating the impact of the COVID-19 pandemic on out-of-hospital cardiac arrest burden of disease in the United States

Background

The impact of the COVID-19 pandemic on out-of-hospital cardiac arrest (OHCA) burden of disease in the United States is unknown. We sought to estimate and compare disability-adjusted life years (DALYs) lost because of OHCA during the COVID-19 pandemic to prepandemic values.

Methods

DALY were calculated as the sum of years of life lost (YLL) and years lived with disability (YLD). Adult non-traumatic emergency medical services-treated OHCA from the Cardiac Arrest Registry to Enhance Survival database for 2016 to 2020 were used to estimate YLL. Cerebral performance category score disability weights were used to estimate YLD. The calculated DALY for the study population was extrapolated to a national level to estimate total US DALY. Data were reported as DALY total and rate. Data for 2020 (pandemic) were compared prepandemic years (2016-2019) via the chi-square test or t-test, as appropriate.

Results

A total of 440,438 OHCA met study inclusion criteria. Total OHCA DALY in the United States increased from 4,468,155 (YLL = 4,463,988; YLD = 4167) in 2019 to 5,379,660 (YLL = 5,375,464; YLD = 4197) in 2020. The DALY rate increased from 1357 per 100,000 individuals in 2019 to 1630 per 100,000 individuals in 2020. Bystander cardiopulmonary resuscitation (CPR) rates did not significantly change (47.96% in 2016-2019 vs. 47.89% in 2020; p = 0.157).

Conclusion

The overall burden of disease because of adult OHCA increased significantly during the COVID-19 pandemic. We observed no change in the willingness of layperson bystanders to perform CPR on a national level in the United States.

ECPR2: Expert Consensus on PeRcutaneous Cannulation for Extracorporeal CardioPulmonary Resuscitation

AIM

Extracorporeal cardiopulmonary resuscitation (ECPR) has emerged as a promising resuscitation strategy for select patients suffering from refractory out-of-hospital cardiac arrest (OHCA), though limited data exist regarding the best practices for ECPR initiation after OHCA.

METHODS

We utilized a modified Delphi process consisting of two survey rounds and a virtual consensus meeting to systematically identify detailed best practices for ECPR initiation following adult non-traumatic OHCA. A modified Delphi process builds content validity and is an accepted method to develop consensus by eliciting expert opinions through multiple rounds of questionnaires. Consensus was achieved when items reached a high level of agreement, defined as greater than 80% responses for a particular item rated a 4 or 5 on a 5-point Likert scale.

RESULTS

Snowball sampling generated a panel of 14 content experts, composed of physicians from four continents and five primary specialties. Seven existing institutional protocols for ECPR cannulation following OHCA were identified and merged into a single comprehensive list of 207 items. The panel reached consensus on 101 items meeting final criteria for inclusion: Prior to Patient Arrival (13 items), Inclusion Criteria (8), Exclusion Criteria (7), Patient Arrival (8), ECPR Cannulation (21), Go On Pump (18), and Post-Cannulation (26).

CONCLUSION

We present a list of items for ECPR initiation following adult nontraumatic OHCA, generated using a modified Delphi process from an international panel of content experts. These findings may benefit centers currently performing ECPR in quality assurance and serve as a template for new ECPR programs.

Annual and lifetime economic productivity loss due to adult out-of-hospital cardiac arrest in the United States: A study for the CARES Surveillance Group

OBJECTIVE

To estimate the annual and lifetime economic productivity loss due to adult out-of-hospital cardiac arrest (OHCA) in the United States (U.S.).

METHODS

All adult (age ≥ 18 years) non-traumatic EMS-treated OHCA with complete data for age, sex, race, and survival outcomes from the CARES database for 2013-2018 were included. Annual and lifetime labor productivity values, based on age and gender, were obtained from previously published national economic data. Productivity losses for OHCA events were calculated by year in U.S. dollars. Productivity losses for survivors were assigned by cerebral performance category score (CPC): CPC 1 and 2 = 0% productivity loss; CPC 3-5 = 100% productivity loss. Sensitivity analyses were performed assigning CPC 2 varying productivity losses (0-100%) based on CPC score and discharge location. Lifetime productivity values assumed 1% annual growth and 3% discount rate and were adjusted for inflation based on 2016 values. Results were extrapolated to annual U.S. population estimates for the study period.

RESULTS

A total of 338,492 (96.5%) cases met inclusion criteria. The mean annual and lifetime productivity losses per OHCA in 2018 were $48,224 and $638,947 respectively. The total annual economic productivity loss due to OHCA in the U.S. increased from $7.4B in 2013 to $11.3B in 2018. Lifetime economic productivity loss increased from $95.2B in 2013 to $150.2B in 2018. Sensitivity analyses yielded similar findings. Per annual death, OHCA ranked third ($10.2B) in annual economic productivity loss in the U.S. behind cancer ($22.9B) and heart disease ($20.3B) in 2018.

CONCLUSION

Adult non-traumatic OHCA events are associated with significant annual and lifetime economic productivity losses and should be the focus of public health resources to improve preventative measures and survival outcomes.