Rationale, Methodology, and Implementation of a Dispatcher-assisted Cardiopulmonary Resuscitation Trial in the Asia-Pacific (Pan-Asian Resuscitation Outcomes Study Phase 2).

Abstract Background. Survival outcomes from out-of-hospital cardiac arrest (OHCA) in Asia are poor (2-11%). Bystander cardiopulmonary resuscitation (CPR) rates are relatively low in Asia. Dispatcher-assisted CPR (DA-CPR) has recently emerged as a potentially cost-effective intervention to increase bystander CPR and survival from OHCA. The Pan-Asian Resuscitation Outcomes Study (PAROS), an Asia-Pacific cardiac arrest registry, was set up in 2009, with the aim of understanding OHCA as a disease in Asia and improving OHCA survival. The network has adopted DA-CPR as part of its strategy to improve OHCA survival. Objective. This article aims to describe the conceptualization, study design, potential benefits, and difficulties for implementation of DA-CPR trial in the Asia-Pacific. Methods. Two levels of intervention, basic and comprehensive, will be offered to PAROS participating sites. The basic level consists of implementation of a DA-CPR protocol and training program, while the comprehensive level consists of implementation of the basic level, with the addition of a dispatch quality measurement tool, quality improvement program, and community education program. Sites that are not able to implement the package will contribute control data. The primary outcome of the study is survival to hospital discharge or survival to 30 days post cardiac arrest. DA-CPR and bystander CPR are secondary outcomes. Conclusion. Implementation of DA-CPR requires concerted efforts by EMS leaders and supervisors, dispatchers, hospital stakeholders, policy makers, and the general public. The DA-CPR trial implemented by the PAROS sites, if successful, can serve as a model for other countries considering such an intervention in their EMS systems.

Prediction of ROSC After Cardiac Arrest Using Machine Learning.

Out-of-hospital cardiac arrest (OHCA) is an important public health problem, with very low survival rate. In treating OHCA patients, the return of spontaneous circulation (ROSC) represents the success of early resuscitation efforts. In this study, we developed a machine learning model to predict ROSC and compared it with the ROSC after cardiac arrest (RACA) score. Results demonstrated the usefulness of machine learning in deriving predictive models.

Impact of population aging on the presentation of out-of-hospital cardiac arrest in the Pan Asian Resuscitation Outcomes Study.

AIM: As a population ages, it can impact on the characteristics and outcomes of cardiogenic out-of-hospital cardiac arrest (OHCA) patients. This study aimed to evaluate the relationship between the age incidence of cardiogenic OHCA and population aging. METHODS: This was a post-hoc analysis of the Pan Asian Resuscitation Outcomes Study (PAROS) database. Data on the population old-age dependency ratio (i.e. elderly/non-elderly) were extracted from publicly accessible sources (United Nations and World Health Organization). RESULTS: We analyzed 40,872 OHCA cases from seven PAROS countries over the period 2009 to 2013. We found significant correlation between the population old-age dependency ratio and elderly/non-elderly ratio in OHCA patients (r = 0.92, P = 0.003). There was a significant correlation between the population old-age dependency ratio and risk differences of 30-day survival rates for non-elderly and elderly OHCA patients (r = 0.89, P = 0.007). CONCLUSIONS: Our findings suggest that the proportion of elderly among OHCA patients will increase, and outcomes could increasingly differ between elderly and non-elderly as a society ages progressively. This has implications for planning and delivery of emergency services as a society ages.

Validation of the ROSC after cardiac arrest (RACA) score in Pan-Asian out-of-hospital cardiac arrest patients.

AIM: Survival is the most consistently captured outcome across countries for out-of-hospital cardiac arrests (OHCA), with return of spontaneous circulation (ROSC) representing the earliest endpoint for 'unbiased' initial resuscitation success. The ROSC after cardiac arrest (RACA) score was developed to predict ROSC and has been validated in several European countries. In this study, we aimed to evaluate the performance of RACA in a Pan-Asian population. METHODS: We conducted a retrospective analysis of data collected in the Pan-Asian Resuscitation Outcomes Study (PAROS) registry. We included OHCA cases from seven communities (Japan, South Korea, Malaysia, Singapore, Taiwan, Thailand, and United Arab Emirates) between January 2009 and December 2012. Paediatric cases, cases that were conveyed by non-emergency medical services (EMS), and cases with incomplete records were excluded from the study. RESULTS: The RACA score showed similar discrimination performance as the original German study and various European validation studies. However, it had poor calibration with the original constant regression coefficient, which was primarily due to the low ROSC rate (8.2%) in the PAROS cohort. The calibration performance of RACA significantly improved after the constant coefficient was modified to adjust for the disparity in ROSC rates between Asia and Europe. CONCLUSION: This is the largest validation study of the RACA score. RACA consistently performs well in both Pan-Asian and European communities and can thus be a valuable tool for evaluating EMS systems. However, to implement it, the constant coefficient has to be modified in the RACA formula with local historical data.

Effect of known history of heart disease on survival outcomes after out-of-hospital cardiac arrests.

OBJECTIVE: We aimed to investigate the effect of known heart disease on post-out-of-hospital cardiac arrest (OHCA) survival outcomes, and its association with factors influencing survival. METHODS: This was an observational, retrospective study involving an OHCA database from seven Asian countries in 2009-2012. Heart disease was defined as a documented diagnosis of coronary artery disease or congenital heart disease. Patients with non-traumatic arrests for whom resuscitation was attempted and with known medical histories were included. Differences in demographics, arrest characteristics and survival between patients with and without known heart disease were analysed. Multivariate logistic regression was performed to identify factors influencing survival to discharge. RESULTS: Of 19 044 eligible patients, 5687 had known heart disease. They were older (77 vs 72 years) and had more comorbidities like diabetes (40.9 vs 21.8%), hypertension (60.6 vs 36.0%) and previous stroke (15.2 vs 10.1%). However, they were not more likely to receive bystander cardiopulmonary resuscitation (P = 0.205) or automated external defibrillation (P = 0.980). On univariate analysis, known heart disease was associated with increased survival (unadjusted odds ratio 1.16, 95% confidence interval 1.03-1.30). However, on multivariate analysis, heart disease predicted poorer survival (adjusted odds ratio 0.76, 95% confidence interval 0.58-1.00). Other factors influencing survival corresponded with previous reports. CONCLUSIONS: Known heart disease independently predicted poorer post-OHCA survival. This study may provide information to guide future prospective studies specifically looking at family education for patients with heart disease and the effect on OHCA outcomes.

Epidemiology and outcome of paediatric out-of-hospital cardiac arrests: A paediatric sub-study of the Pan-Asian resuscitation outcomes study (PAROS).

BACKGROUND: The Pan Asian Resuscitation Outcomes Study (PAROS) is a retrospective study of out- of-hospital cardiac arrest(OHCA), collaborating with EMS agencies and academic centers in Japan, South Korea, Malaysia, Singapore, Taiwan, Thailand and UAE-Dubai. The objectives of this study is to describe the characteristics and outcomes, and to find factors associated with survival after paediatric OHCA. METHODS: We studied all children less than 17 years of age with OHCA conveyed by EMS and non-EMS transports from January 2009 to December 2012. We did univariate and multivariate logistic regression analyses to assess the factors associated with survival-to-discharge outcomes. RESULTS: A total of 974 children with OHCA were included. Bystander cardiopulmonary resuscitation rates ranged from 53.5% (Korea), 35.6% (Singapore) to 11.8% (UAE). Overall, 8.6% (range 0%-9.7%) of the children survived to discharge from hospital. Adolescents (13-17 years) had the highest survival rate of 13.8%. 3.7% of the children survived with good neurological outcomes of CPC 1 or 2. The independent pre-hospital factors associated with survival to discharge were witnessed arrest and initial shockable rhythm. In the sub-group analysis, pre-hospital advanced airway [odds ratio (OR) = 3.35, 95% confidence interval (CI) = 1.23-9.13] was positively associated with survival-to-discharge outcomes in children less than 13 years-old. Among adolescents, bystander CPR (OR = 2.74, 95%CI = 1.03-7.3) and initial shockable rhythm (OR = 20.51, 95%CI = 2.15-195.7) were positive factors. CONCLUSION: The wide variation in the survival outcomes amongst the seven countries in our study may be due to the differences in the delivery of pre-hospital interventions and bystander CPR rates.

Outcomes for out-of-hospital cardiac arrests across 7 countries in Asia: The Pan Asian Resuscitation Outcomes Study (PAROS).

BACKGROUND: The Pan Asian Resuscitation Outcomes Study (PAROS) Clinical Research Network (CRN) was established in collaboration with emergency medical services (EMS) agencies and academic centers in Japan, Singapore, South Korea, Malaysia, Taiwan, Thailand, and UAE-Dubai and aims to report out-of-hospital cardiac arrests (OHCA) and provide a better understanding of OHCA trends in Asia. METHODS AND RESULTS: This is a prospective, international, multi-center cohort study of OHCA across the Asia-Pacific. Each participating country provided between 1.5 and 2.5 years of data from January 2009 to December 2012. All OHCA cases conveyed by EMS or presenting at emergency departments were captured. 66,780 OHCA cases were submitted to the PAROS CRN; 41,004 cases were presumed cardiac etiology. The mean age OHCA occurred varied from 49.7 to 71.7 years. The proportion of males ranged from 57.9% to 82.7%. Proportion of unwitnessed arrests ranged from 26.4% to 67.9%. Presenting shockable rhythm rates ranged from 4.1% to 19.8%. Bystander cardiopulmonary resuscitation (CPR) rates varied from 10.5% to 40.9%, however <1.0% of these arrests received bystander defibrillation. For arrests that were with cardiac etiology, witnessed arrest and VF, the survival rate to hospital discharge varied from no reported survivors to 31.2%. Overall survival to hospital discharge varied from 0.5% to 8.5%. Survival with good neurological function ranged from 1.6% to 3%. CONCLUSIONS: Survival to hospital discharge for Asia varies widely and this may be related to patient and system differences. This implies that survival may be improved with interventions such as increasing bystander CPR, public access defibrillation and improving EMS.

Does pre-hospital endotracheal intubation improve survival in adults with non-traumatic out-of-hospital cardiac arrest? A systematic review.

INTRODUCTION: Endotracheal intubation (ETI) is currently considered superior to supraglottic airway devices (SGA) for survival and other outcomes among adults with non-traumatic out-of-hospital cardiac arrest (OHCA). We aimed to determine if the research supports this conclusion by conducting a systematic review. METHODS: We searched the MEDLINE, Scopus and CINAHL databases for studies published between January 1, 1980, and 30 April 30, 2013, which compared pre-hospital use of ETI with SGA for outcomes of return of spontaneous circulation (ROSC); survival to hospital admission; survival to hospital discharge; and favorable neurological or functional status. We selected studies using pre-specified criteria. Included studies were independently screened for quality using the Newcastle-Ottawa scale. We did not pool results because of study variability. Study outcomes were extracted and results presented as summed odds ratios with 95% CI. RESULTS: We identified five eligible studies: one quasi-randomized controlled trial and four cohort studies, involving 303,348 patients in total. Only three of the five studies reported a higher proportion of ROSC with ETI versus SGA with no difference reported in the remaining two. None found significant differences between ETI and SGA for survival to hospital admission or discharge. One study reported better functional status at discharge for ETI versus SGA. Two studies reported no significant difference for favorable neurological status between ETI and SGA. CONCLUSION: Current evidence does not conclusively support the superiority of ETI over SGA for multiple outcomes among adults with OHCA.