Modifiable Factors Associated With Survival After Out-of-Hospital Cardiac Arrest in the Pan-Asian Resuscitation Outcomes Study

doi:10.1016/j.annemergmed.2017.07.484

Annals of Emergency Medicine

Volume 71, Issue 5, May 2018, Pages 608-617.e15

Presented as an abstract at the Singapore Cardiac Society annual scientific meeting, April 2015, Singapore; European Resuscitation Council, October 2015, Prague, Czech Republic; Asian Conference for Emergency Medicine, November 2015, Taipei, Taiwan; and the Society for Emergency Medicine in Singapore annual scientific meeting, International Resuscitation Science Symposium, February 2016, Singapore.

https://doi.org/10.1016/j.annemergmed.2017.07.484 Get rights and content

Study objective

The study aims to identify modifiable factors associated with improved out-of-hospital cardiac arrest survival among communities in the Pan-Asian Resuscitation Outcomes Study (PAROS) Clinical Research Network: Japan, Singapore, South Korea, Malaysia, Taiwan, Thailand, and the United Arab Emirates (Dubai).

Methods

This was a prospective, international, multicenter cohort study of out-of-hospital cardiac arrest in the Asia-Pacific. Arrests caused by trauma, patients who were not transported by emergency medical services (EMS), and pediatric out-of-hospital cardiac arrest cases (<18 years) were excluded from the analysis. Modifiable out-of-hospital factors (bystander cardiopulmonary resuscitation [CPR] and defibrillation, out-of-hospital defibrillation, advanced airway, and drug administration) were compared for all out-of-hospital cardiac arrest patients presenting to EMS and participating hospitals. The primary outcome measure was survival to hospital discharge or 30 days of hospitalization (if not discharged). We used multilevel mixed-effects logistic regression models to identify factors independently associated with out-of-hospital cardiac arrest survival, accounting for clustering within each community.

Results

Of 66,780 out-of-hospital cardiac arrest cases reported between January 2009 and December 2012, we included 56,765 in the analysis. In the adjusted model, modifiable factors associated with improved out-of-hospital cardiac arrest outcomes included bystander CPR (odds ratio [OR] 1.43; 95% confidence interval [CI] 1.31 to 1.55), response time less than or equal to 8 minutes (OR 1.52; 95% CI 1.35 to 1.71), and out-of-hospital defibrillation (OR 2.31; 95% CI 1.96 to 2.72). Out-of-hospital advanced airway (OR 0.73; 95% CI 0.67 to 0.80) was negatively associated with out-of-hospital cardiac arrest survival.

Conclusion

In the PAROS cohort, bystander CPR, out-of-hospital defibrillation, and response time less than or equal to 8 minutes were positively associated with increased out-of-hospital cardiac arrest survival, whereas out-of-hospital advanced airway was associated with decreased out-of-hospital cardiac arrest survival. Developing EMS systems should focus on basic life support interventions in out-of-hospital cardiac arrest resuscitation.

Introduction

The incidence of out-of-hospital cardiac arrest ranges from 50 to 60 per 100,000 person-years globally.¹ Out-of-hospital cardiac arrest registries in the United States2, 3 and Europe4, 5 have reported survival rates ranging from 7.5% to 10.8%. However, out-of-hospital cardiac arrest survival in Asia is lower. The Pan-Asian Resuscitation Outcomes Study (PAROS) registry has observed an out-of-hospital cardiac arrest survival rate of only 5.4%.⁶ This finding implies that survival can be improved further in out-of-hospital cardiac arrest systems in Asia.

Editor’s Capsule Summary

What is already known on this topic

Out-of-hospital cardiac arrest survival in Asia is low.

What question this study addressed

What modifiable factors are associated with improved out-of-hospital cardiac arrest survival in Asian communities?

What this study adds to our knowledge

In this analysis of 56,765 out-of-hospital cardiac arrests from communities of the Pan-Asian Resuscitation Outcomes Study network, bystander cardiopulmonary resuscitation, response time less than or equal to 8 minutes, and out-of-hospital defibrillation were associated with improved out-of-hospital cardiac arrest survival. Out-of-hospital advanced airway was associated with decreased out-of-hospital cardiac arrest survival.

How this is relevant to clinical practice

These results highlight potential targets for improving out-of-hospital cardiac arrest survival in Asia.

North American studies have identified several modifiable factors in the chain of survival⁷ (eg, bystander cardiopulmonary resuscitation [CPR], defibrillation) associated with out-of-hospital cardiac arrest survival.⁸ The importance of these factors in Asian communities is unknown. For example, although countries such as Japan, Korea, Singapore, and Taiwan have well-established emergency medical services (EMS) systems (availability of dispatcher-assisted CPR, first responders, universal dispatch, etc), they are still lacking in advanced life support (ALS) capabilities, such as administration of amiodarone and intubation by the paramedics. Public awareness of and provision of CPR also lags behind those of Western nations. Hence, the elements pertinent to out-of-hospital cardiac arrest survival in Asia likely differ from those reported by previous North American studies.

In a limited-resource setting, countries will need to prioritize where to invest efforts to improve their out-of-hospital cardiac arrest systems. For example, it is not clear whether developing countries should focus on developing ALS capabilities or improving community CPR training.⁹ An improved understanding of the relative influence of these factors on out-of-hospital cardiac arrest outcomes could influence public policy and guide these countries to the best strategies for improving out-of-hospital cardiac arrest outcomes.

The objective of this study was to identify the relative importance of major systemic, modifiable factors associated with out-of-hospital cardiac arrest survival in the communities of the PAROS consortium.

Section snippets

Study Design

We analyzed out-of-hospital cardiac arrest data from the PAROS network. The study was approved by the local ethics committees of the participating PAROS communities.

Setting

PAROS is a clinical research network established by EMS and emergency medicine experts for the purpose of conducting research in out-of-hospital emergency care in the Asia-Pacific. The network has identified out-of-hospital cardiac arrest as its main focus and aims to improve out-of-hospital cardiac arrest survival through the

Results

Of 66,780 out-of-hospital cardiac arrest cases reported between January 2009 and December 2012, we excluded 10,015 trauma, non-EMS, and pediatric (<18 years) cases, leaving 56,765 cases in the analysis (Figure 1). The mean age of the population was 72.7 years; 59.6% were men (Table 1). Approximately 10.1% of the patients had heart disease. Most out-of-hospital cardiac arrests occurred at home (68.8%) and were unwitnessed (57.1%). The initial arrest rhythm was mostly nonshockable (87.6%). More

Limitations

This was not a prospective interventional trial. Cases from Japan made up 75% of the study population, but we observed consistent results when separately assessing Japan and the remaining PAROS communities. Although a small portion of cases (0.58%) were missing survival outcome data, this did not affect our results in the sensitivity analysis.

Because the PAROS registry is EMS based, we may have missed patients not receiving EMS care, a situation that often occurs in Thailand and Malaysia.

Discussion

In this study of out-of-hospital cardiac arrest treated in the PAROS communities, we found that bystander CPR, out-of-hospital defibrillation, and EMS response time less than or equal to 8 minutes were positively associated with out-of-hospital cardiac arrest outcomes, whereas out-of-hospital advanced airway and drug administration were negatively associated with out-of-hospital cardiac arrest survival. These associations remained consistent in sensitivity analyses. Our results are similar to

References (31)

M.R. Daya et al.
Out-of-hospital cardiac arrest survival improving over time: results from the Resuscitation Outcomes Consortium (ROC)
Resuscitation
(2015)
M.E.H. Ong et al.
Outcomes for out-of-hospital cardiac arrests across 7 countries in Asia: the Pan Asian Resuscitation Outcomes Study (PAROS)
Resuscitation
(2015)
I.G. Stiell et al.
Modifiable factors associated with improved cardiac arrest survival in a multicenter basic life support/defibrillation system: OPALS study phase I results. Ontario Prehospital Advanced Life Support
Ann Emerg Med
(1999)
G. Bakalos et al.
Advanced life support versus basic life support in the pre-hospital setting: a meta-analysis
Resuscitation
(2011)
J. McMullan et al.
Airway management and out-of-hospital cardiac arrest outcome in the CARES registry
Resuscitation
(2014)
M.L. Weisfeldt et al.
Survival after application of automatic external defibrillators before arrival of the emergency medical system: evaluation in the Resuscitation Outcomes Consortium population of 21 million
J Am Coll Cardiol
(2010)
G. Nichol et al.
Cost-effectiveness analysis of potential improvements to emergency medical services for victims of out-of-hospital cardiac arrest
Ann Emerg Med
(1996)
R.B. Vukmir
Survival from prehospital cardiac arrest is critically dependent upon response time
Resuscitation
(2006)
L.B. Becker et al.
Outcome of CPR in a large metropolitan area—where are the survivors?
Ann Emerg Med
(1991)
D.C. Cone
The eight-minute defibrillation response interval debunked: or is it?
Ann Emerg Med
(2003)

R. White et al.

High discharge survival rate after out-of-hospital ventricular fibrillation with rapid defibrillation by police and paramedics

Ann Emerg Med

(1996)

S.D. Shin et al.

Out-of-hospital airway management and cardiac arrest outcomes: a propensity score matched analysis

Resuscitation

(2012)

I.G. Jacobs et al.

Effect of adrenaline on survival in out-of-hospital cardiac arrest: a randomised double-blind placebo-controlled trial

Resuscitation

(2011)

G. Nichol et al.

Regional variation in out-of-hospital cardiac arrest incidence and outcome

JAMA

(2008)

B. McNally et al.

Out-of-hospital cardiac arrest surveillance—Cardiac Arrest Registry to Enhance Survival (CARES), United States, October 1, 2005–December 31, 2010

MMWR Surveill Summ

(2011)

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A growing number out-of-hospital cardiac arrest (OHCA) registries have been developed across the globe. A few of these are national, while others cover larger geographical regions. These registries have common objectives; continuous quality improvement, epidemiological research and providing infrastructure for clinical trials. OHCA registries make performance comparison across Emergency Medical Services systems possible for benchmarking, hypothesis generation and further research. Changes in OHCA incidence and outcomes provide insights about the effects of secular trends or health services interventions. These registries, therefore, have become a mainstay of OHCA management and research. However, developing and maintaining these registries is challenging. Coordination of different service providers to support data collection, sustainable resourcing, data quality and data security are the key challenges faced by these registries.
Despite all these challenges, noteworthy progress has been made and further standardization and co-ordination across registries can result in great international benefit. In this paper we present a ‘why’ and ‘how to’ model for setting up OHCA registries, and suggestions for better international co-ordination through a Global OHCA Registries Collaborative (GOHCAR). We draw together the knowledge of a cohort of international researchers, with experience and expertise in OHCA registry development, management, and data synthesis.
Wolf creek XVII part 4: Amplifying lay-rescuer response
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Amplifying lay-rescuer response is a key priority to increase survival from out-of-hospital cardiac arrest (OHCA). We describe the current state of lay-rescuer response, how we envision the future, and the gaps, barriers, and research priorities that will amplify response to OHCA.
‘Amplifying Lay-Rescuer Response’ was one of six focus topics for the Wolf Creek XVII Conference held on June 14–17, 2023, in Ann Arbor, Michigan, USA. Conference invitees included international thought leaders and scientists in the field of cardiac arrest resuscitation from academia and industry. Participants submitted via online survey knowledge gaps, barriers to translation and research priorities for each focus topic. Expert panels used the survey results and their own perspectives and insights to create and present a preliminary unranked list for each category that was debated, revised and ranked by all attendees to identify the top 5 for each category.
The top five knowledge gaps as ranked by the panel, reflected a recognition of the need to better understand the psycho-social aspects of lay response. The top five barriers to translation reflected issues at the individual, community, societal, structural, and governmental levels. The top five research priorities were focused on understanding the social/psychological and emotional barriers to action, finding the most effective/cost-effective strategies to educate lay persons and implement community life-saving interventions, evaluation of new technological solutions and how to enhance the role of dispatch working with lay-rescuers.
Future research in lay rescuer response should incorporate technology innovations, understand the “humanity” of the situation, leverage implementation science and systems thinking to save lives. This will require the field of resuscitation to engage with scholars outside our traditional ranks and to be open to new ways of thinking about old problems.
Lower versus higher oxygen targets after resuscitation from out-of-hospital cardiac arrest: A systematic review and meta-analysis of randomized controlled trials
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We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing lower versus higher oxygen targets on the outcomes among adults resuscitated from OHCA. The primary outcome was short-term survival (in hospital or within 30 days). Subgroup analyses were performed according to timing of study interventions.
Seven RCTs with 1454 patients were finally included. The short-term survival did not differ between the two groups with a relative risk (RR) of 0.98 (95% CI, 0.86 to 1.11). There were no significant differences in survival at longest follow-up (RR, 1.01; 95% CI, 0.91 to 1.14), favorable neurological outcome (RR, 1.00; 95% CI, 0.91 to 1.11), length of intensive care unit stay (mean difference, −4.94 h; 95% CI, −14.83 to 4.96 h), or risk of re-arrest (RR, 0.68; 95% CI, 0.21 to 2.19). The quality of evidence ranged from moderate to very low.
Current evidence suggests that targeting a lower or higher oxygen therapy in patients after resuscitation from OHCA results in similar short-term survival and other clinical outcomes.
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Early prediction of outcomes after cardiopulmonary arrest (CPA) is important for considering the best support. Our purpose was to evaluate predictors of the 30-day mortality in patients with CPA after return of spontaneous circulation (ROSC) and to assess an equation for calculating the 30-day mortality using clinical parameters.
We retrospectively analyzed the data of 194 consecutive patients with CPA and ROSC in a derivation study (2015–2022). We compared clinical parameters between the survived (n = 78) and dead (n = 116) patients. We derived an equation for estimated probability of death based on clinical parameters, using multivariate logistic regression analysis. The reliability of the equation was validated in 80 additional patients with CPA.
The 30-day mortality was associated with sex, witnessed cardiac arrest, bystander cardiopulmonary resuscitation (CPR), CPA due to acute myocardial infarction, pupil diameter, Glasgow Coma Scale score (GCS), presence of light reflex, arterial or venous pH, lactate levels, initial ventricular fibrillation (VF), CPA time, and age. The derived logistic regression equation was as follows: Estimated probability of death = 1 / (1 + e^-x), x = (0.25 × bystander CPR) + (0.44 × pupil diameter) – (0.14 × GCS) + (0.09 × lactate) – (1.87 × initial VF) + (0.07 × CPA time) + (0.05 × age) - 7.03. The cut-off value for estimated probability of death calculated by this equation was 54.5 %, yielding a sensitivity, specificity, and accuracy of 86.2 %, 80.8 %, and 84.5 %, respectively. In the validation model, these values were 81.8 %, 85.7 %, and 82.5 %, respectively.
The 30-day mortality may be calculated after ROSC in patients with CPA using simple clinical parameters. This equation may facilitate further best support for patients with CPA.
Determinants of health-related quality of life after out-of-hospital cardiac arrest (OHCA): A systematic review
2023, Resuscitation
With a growing number of out-of-hospital cardiac arrest (OHCA) survivors globally, the focus of OHCA management has now broadened to survivorship. An outcome central to survivorship is health-related quality of life (HRQoL). This systematic review aimed to synthesise evidence related to the determinants of HRQoL of OHCA survivors.
We systematically searched MEDLINE, Embase, and Scopus from inception to 15 August 2022 to identify studies investigating the association of at least one determinant and HRQoL in adult OHCA survivors. All articles were independently reviewed by two investigators. We abstracted data pertaining to determinants and classified them using a well-established HRQoL theoretical framework – the Wilson and Cleary (revised) model.
31 articles assessing a total of 35 determinants were included. Determinants were classified into the five domains in the HRQoL model. 26 studies assessed determinants related to individual characteristics (n = 3), 12 studied biological function (n = 7), nine studied symptoms (n = 3), 16 studied functioning (n = 5), and 35 studied characteristics of the environment (n = 17). In studies that included multivariable analyses, most reported that individual characteristics (older age, female sex), symptoms (anxiety, depression), and functioning (impaired neurocognitive function) were significantly associated with poorer HRQoL.
Individual characteristics, symptoms, and functioning played significant roles in explaining the variability in HRQoL. Significant non-modifiable determinants such as age and sex could be used to identify populations at risk of poorer HRQoL, while significant modifiable determinants such as psychological health and neurocognitive functioning could serve as targets for post-discharge screening and rehabilitation plans.
PROSPERO registration number: CRD42022359303.

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: Please see page 609 for the Editor’s Capsule Summary of this article.

: Supervising editor: Henry E. Wang, MD, MS

: ∗Dr. Lee is currently affiliated with the Department of Emergency Medicine, Inje University Seoul Paik Hospital, Seoul, South Korea.

: Author contributions: HT, MEHO, MH-MM, and SDS conceived the study objectives and methodology and prepared the study protocol. All authors gave input to the design of the study, including the development of the study variables, data dictionary, and case record form. HT, MEHO, MH-MM, HK, KWL, KK, C-HL, HNG, OA, PK, NHR, NED, and SDS assisted in preparation and administration of the study and data acquisition. All authors assisted in data clarification and writing and review of the article. FJS and PA were responsible for all statistical analyses. HT had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. All authors endorse the data and conclusions. HT takes responsibility for the paper as a whole.

: All authors attest to meeting the four ICMJE.org authorship criteria: (1) Substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work; AND (2) Drafting the work or revising it critically for important intellectual content; AND (3) Final approval of the version to be published; AND (4) Agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

: Funding and support: By Annals policy, all authors are required to disclose any and all commercial, financial, and other relationships in any way related to the subject of this article as per ICMJE conflict of interest guidelines (see www.icmje.org). Dr. Ong reports funding from the Zoll Medical Corporation for a study involving mechanical cardiopulmonary resuscitation devices; grants from the Laerdal Foundation, Laerdal Medical, and Ramsey Social Justice Foundation for funding of the Pan-Asian Resuscitation Outcomes Study; an advisory relationship with Global Healthcare Singapore, a commercial entity that manufactures cooling devices; and funding from Laerdal Medical on an observation program to their Community CPR Training Centre Research Program in Norway. This study was supported by grants from the National Medical Research Council (Singapore), Ministry of Health, Singapore, and Korea Centers for Disease Control and Prevention. This study is supported by grants from the National Medical Research Council (Singapore), Ministry of Health, Singapore, and Korea Centers for Disease Control and Prevention.

: The funders had no involvement in the study design; in the collection, analysis, and interpretation of data; in the writing of the article; and in the decision to submit the article for publication.

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: A podcast for this article is available at www.annemergmed.com.

^†: All investigators are listed in the Appendix.

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Emergency medical services/original researchModifiable Factors Associated With Survival After Out-of-Hospital Cardiac Arrest in the Pan-Asian Resuscitation Outcomes Study

Study objective

Methods

Results

Conclusion

Introduction

Editor’s Capsule Summary

Section snippets

Study Design

Setting

Results

Limitations

Discussion

Resuscitation

Resuscitation

Ann Emerg Med

Resuscitation

Resuscitation

J Am Coll Cardiol

Ann Emerg Med

Resuscitation

Ann Emerg Med

Ann Emerg Med

Ann Emerg Med

Resuscitation

Resuscitation

Regional variation in out-of-hospital cardiac arrest incidence and outcome

JAMA

Out-of-hospital cardiac arrest surveillance—Cardiac Arrest Registry to Enhance Survival (CARES), United States, October 1, 2005–December 31, 2010

MMWR Surveill Summ

Emergency medical services/original research
Modifiable Factors Associated With Survival After Out-of-Hospital Cardiac Arrest in the Pan-Asian Resuscitation Outcomes Study