What change in outcomes after cardiac arrest is necessary to change practice? Results of an international survey.

BACKGROUND: Efficient trials of interventions for patients with out-of-hospital cardiac arrest (OHCA) should have adequate but not excess power to detect a difference in outcomes. The minimum clinically important difference (MCID) is the threshold value in outcomes observed in a trial at which providers should choose to adopt a treatment. There has been limited assessment of MCID for outcomes after OHCA. Therefore, we conducted an international survey of individuals interested in cardiac resuscitation to define the MCID for a range of outcomes after OHCA. METHODS: A brief survey instrument was developed and modified by consensus. Included were open-ended responses. The survey included an illustrative example of a hypothetical randomized study with distributions of outcomes based on those in a public use datafile from a previous trial. Elicited information included the minimum significant difference required in an outcome to change clinical practice. The population of interest was emergency physicians or other practitioners of acute cardiovascular research. RESULTS: Usable responses were obtained from 160 respondents (50% of surveyed) in 46 countries (79% of surveyed). MCIDs tended to increase as baseline outcomes increased. For a population of patients with 25% survival to discharge and 20% favorable neurologic status at discharge, the MCID were median 5 (interquartile range [IQR] 3, 10) percent for survival to discharge; median 5 (IQR 2, 10) percent for favorable neurologic status at discharge, median 4 (IQR 2, 9) days of ICU-free survival and median 4 (IQR 2, 8) days of hospital-free survival. CONCLUSION: Reported MCIDs for outcomes after OHCA vary according to the outcome considered as well as the baseline rate of achieving it. MCIDs of ICU-free survival or hospital-free survival may be useful to accelerate the rate of evidence-based change in resuscitation care.

Associations between gender and cardiac arrest outcomes in Pan-Asian out-of-hospital cardiac arrest patients.

BACKGROUND: The incidence of out-of-hospital cardiac arrest (OHCA) in women is thought to be lower than that of men, with better outcomes in some Western studies. OBJECTIVES: This study aimed to investigate the effect of gender on OHCA outcomes in the Pan-Asian population. METHODOLOGY: This was a retrospective, secondary analysis of the Pan Asian Resuscitation Outcomes Study (PAROS) data between 2009 and 2012. We included OHCA cases which were presumed cardiac etiology, aged 18 years and above and resuscitation attempted by emergency medical services (EMS) systems. We used multi-level mixed-effects logistic regression models to account for the clustering effect of individuals within the country. Primary outcome was survival to hospital discharge. RESULTS: We included a total of 40,159 OHCA cases, 40% of which were women. We found that women were more likely to be older and have an initial non-shockable arrest rhythm; they were more likely to receive bystander cardio-pulmonary resuscitation (CPR). The univariate analysis showed that women were significantly less likely to have return of spontaneous circulation (ROSC) at scene or in the emergency department (ED), and had lower rates of survival-to-admission and discharge, and poorer overall and cerebral performance outcomes. There was however, no significant gender difference on outcomes after adjustment of other confounders. Women in the reproductive age group (age 18-44 years) were significantly more likely to have ROSC at scene or in the ED, higher rates of survival-to-admission and discharge, and have better overall and cerebral performance outcomes after adjustment for differences in baseline and pre-hospital factors. Menopausal women (age 55 years and above) were less likely to survive to admission after adjusting for other pre-hospital characteristics but not after age adjustment. CONCLUSION: Differences in survival outcomes between reproductive and menopausal women highlight a need for further investigations into the plausible social, pathologic or hormonal basis.

Variation of current protocols for managing out-of-hospital cardiac arrest in prehospital settings among Asian countries.

BACKGROUND/PURPOSE: Protocols for managing patients with out-of-hospital cardiac arrest (OHCA) may vary due to legal, cultural, or socioeconomic concerns. We sought to assess international variation in policies and protocols related to OHCA. METHODS: A brief survey was developed by consensus. Elicited information included protocols for managing patients with nontraumatic OHCA or traumatic OHCA, policies for using automated external defibrillators (AEDs) during transportation of patients with ongoing resuscitation, and application of terminations of resuscitation (TOR) rules in prehospital settings in the respondent's city or country. The populations of interest were emergency physicians, medical directors of emergency medical services (EMS), and policy makers. RESULTS: Responses were obtained from eight cities in six Asian countries. Only one (12.5%) city applied TOR rules for OHCAs. Do-not-resuscitate (DNR) orders were valid in prehospital settings in five (62.5%) cities. All cities used AEDs for nontraumatic OHCAs; seven (87.5%) cities did not routinely use AEDs for traumatic OHCAs. For nontraumatic OHCAs, four (50%) cities performed 2 minutes of on-scene cardiopulmonary resuscitation (CPR) and then transported the patients with ongoing resuscitation to hospitals; three (37.5%) cities performed 4 minutes of on-scene CPR; one (12.5%) city allowed variation in the duration of on-scene CPR. CONCLUSION: International variation in practices and polices related to OHCAs do exist. Concerns regarding prehospital TOR rules include medical evidence, legal considerations, EMS manpower, public perception, medical oversight, education, EMS characteristics, and cost-effectiveness analysis. Further research is needed to achieve consensus regarding management protocols, especially for EMS that perform resuscitation during transportation of OHCA patients.

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.

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.

Comparison of emergency medical services systems in the pan-Asian resuscitation outcomes study countries: Report from a literature review and survey.

OBJECTIVE: Asia-Pacific countries have unique prehospital emergency care or emergency medical services (EMS) systems, which are different from European or Anglo-American models. We aimed to compare the EMS systems of eight Asia-Pacific countries/regions as part of the Pan Asian Resuscitation Outcomes Study (PAROS), to provide a basis for future comparative studies across systems of care. METHODS: In the first phase, a systematic literature review of EMS system within the eight PAROS countries/regions of interest was conducted. In the second phase, PAROS site directors were surveyed for additional information about the demographics and characteristics of EMS services at their sites. RESULTS: The database and bibliography search identified 25 eligible articles. The survey of EMS systems was completed by seven PAROS directors. By combining information sources from phases 1 and 2, we found that all PAROS EMS systems were single-tiered, and most were public (vs private) and fire-based (Thailand, Malaysia, Singapore, Taiwan, Japan, Korea). Ambulance personnel were primarily emergency medical technicians and paramedics, except for Thailand and Turkey, whose personnel include nurses and physicians. Personnel were trained to use automated external defibrillators and have basic cardiac life support certification. The service capability of each EMS system in terms of dispatch, airway management and medications, for example, varied greatly. CONCLUSION: We found variation in the EMS systems across the eight Asia-Pacific countries/regions studied. The findings will inform the construction of a multinational Asia-Pacific research network for future comparative studies and could serve as a model for international research networks.

Comparison of emergency medical services systems across Pan-Asian countries: a Web-based survey.

BACKGROUND: There are great variations in out-of-hospital cardiac arrest (OHCA) survival outcomes among different countries and different emergency medical services (EMS) systems. The impact of different systems and their contribution to enhanced survival are poorly understood. This paper compares the EMS systems of several Asian sites making up the Pan-Asian Resuscitation Outcomes Study (PAROS) network. Some preliminary cardiac arrest outcomes are also reported. METHODS: This is a cross-sectional descriptive survey study addressing population demographics, service levels, provider characteristics, system operations, budget and finance, medical direction (leadership), and oversight. RESULTS: Most of the systems are single-tiered. Fire-based EMS systems are predominant. Bangkok and Kuala Lumpur have hospital-based systems. Service level is relatively low, from basic to intermediate in most of the communities. Korea, Japan, Singapore, and Bangkok have intermediate emergency medical technician (EMT) service levels, while Taiwan and Dubai have paramedic service levels. Medical direction and oversight have not been systemically established, except in some communities. Systems are mostly dependent on public funding. We found variations in available resources in terms of ambulances and providers. The number of ambulances is 0.3 to 3.2 per 100,000 population, and most ambulances are basic life support (BLS) vehicles. The number of human resources ranges from 4.0 per 100,000 population in Singapore to 55.7 per 100,000 population in Taipei. Average response times vary between 5.1 minutes (Tainan) and 22.5 minutes (Kuala Lumpur). CONCLUSION: We found substantial variation in 11 communities across the PAROS EMS systems. This study will provide the foundation for understanding subsequent studies arising from the PAROS effort.