Tatsuya Nishiuchi

Effectiveness of Bystander-Initiated Cardiac-Only Resuscitation for Patients With Out-of-Hospital Cardiac Arrest

Background— Previous animal and clinical studies suggest that bystander-initiated cardiac-only resuscitation may be superior to conventional cardiopulmonary resuscitation (CPR) for out-of-hospital cardiac arrests. Our hypothesis was that both cardiac-only bystander resuscitation and conventional bystander CPR would improve outcomes from out-of-hospital cardiac arrests of ≤15 minutes’ duration, whereas the addition of rescue breathing would improve outcomes for cardiac arrests lasting >15 minutes. Methods and Results— We carried out a prospective, population-based, observational study involving consecutive patients with emergency responder resuscitation attempts from May 1, 1998, through April 30, 2003. The primary outcome measure was 1-year survival with favorable neurological outcome. Multivariable logistic regression analysis was performed to evaluate the relationship between type of CPR and outcomes. Among the 4902 witnessed cardiac arrests, 783 received conventional CPR, and 544 received cardiac-only resuscitation. Excluding very-long-duration cardiac arrests (>15 minutes), the cardiac-only resuscitation yielded a higher rate of 1-year survival with favorable neurological outcome than no bystander CPR (4.3% versus 2.5%; odds ratio, 1.72; 95% CI, 1.01 to 2.95), and conventional CPR showed similar effectiveness (4.1%; odds ratio, 1.57; 95% CI, 0.95 to 2.60). For the very-long-duration arrests, neurologically favorable 1-year survival was greater in the conventional CPR group, but there were few survivors regardless of the type of bystander CPR (0.3% [2 of 624], 0% [0 of 92], and 2.2% [3 of 139] in the no bystander CPR, cardiac-only CPR, and conventional CPR groups, respectively; P<0.05). Conclusions— Bystander-initiated cardiac-only resuscitation and conventional CPR are similarly effective for most adult out-of-hospital cardiac arrests. For very prolonged cardiac arrests, the addition of rescue breathing may be of some help.

Continuous Improvements in “Chain of Survival” Increased Survival After Out-of-Hospital Cardiac Arrests A Large-Scale Population-Based Study

Background— The impact of ongoing efforts to improve the “chain of survival” for out-of-hospital cardiac arrest (OHCA) is unclear. The objective of this study was to evaluate the incremental effect of changes in prehospital emergency care on survival after OHCA. Methods and Results— This prospective, population-based observational study involved consecutive patients with OHCA from May 1998 through December 2006. The primary outcome measure was 1-month survival with favorable neurological outcome. Multiple logistic regression analysis was used to assess factors that were potentially associated with better neurological outcome. Among 42 873 resuscitation-attempted adult OHCAs, 8782 bystander-witnessed arrests of presumed cardiac origin were analyzed. The median time interval from collapse to call for medical help, first cardiopulmonary resuscitation, and first shock shortened from 4 (interquartile range [IQR] 2 to 11) to 2 (IQR 1 to 5) minutes, from 9 (IQR 5 to 13) to 7 (IQR 3 to 11) minutes, and from 19 (IQR 13 to 22) to 9 (IQR 7 to 12) minutes, respectively. Neurologically intact 1-month survival after witnessed ventricular fibrillation increased from 6% (6/96) to 16% (49/297; P<0.001). Among all witnessed OHCAs, earlier cardiopulmonary resuscitation (odds ratio per minute 0.89, 95% confidence interval 0.85 to 0.93) and earlier intubation (odds ratio per minute 0.96, 95% confidence interval 0.94 to 0.99) were associated with better neurological outcome. For ventricular fibrillation, only earlier shock was associated with better outcome (odds ratio 0.84, 95% confidence interval 0.80 to 0.88). Conclusions— Data from a large, population-based cohort demonstrate a continuous increase in OHCA survival with improvement in the chain of survival. The incremental benefit of early advanced care on OHCA survival is also suggested.

Age-Specific Differences in Outcomes After Out-of-Hospital Cardiac Arrests

OBJECTIVE: We assessed out-of-hospital cardiac arrests (OHCAs) for various pediatric age groups. METHODS: This prospective, population-based, observational study included all emergency medical service-treated OHCAs in Osaka, Japan, between 1999 and 2006 (excluding 2004). Patients were grouped as adults (>17 years), infants (<1 year), younger children (1–4 years), older children (5–12 years), and adolescents (13–17 years). The primary outcome measure was 1-month survival with favorable neurologic outcome. RESULTS: Of 950 pediatric OHCAs, resuscitations were attempted for 875 patients (92%; 347 infants, 203 younger children, 135 older children, and 190 adolescents). The overall incidence of nontraumatic pediatric OHCAs was 7.3 cases per 100 000 person-years, compared with 64.7 cases per 100 000 person-years for adults and 65.5 cases per 100 000 person-years for infants. Most infant OHCAs occurred in homes (93%) and were not witnessed (90%). Adolescent OHCAs often occurred outside the home (45%), were witnessed by bystanders (37%), and had shockable rhythms (18%). One-month survival was more common after nontraumatic pediatric OHCAs than adult OHCAs (8% [56 of 740 patients] vs 5% [1677 of 33 091 patients]; adjusted odds ratio: 2.26 [95% confidence interval: 1.63–3.13]). One-month survival with favorable neurologic outcome was more common among children than adults (3% [21 of 740 patients] vs 2% [648 of 33 091 patients]; adjusted odds ratio: 2.46 [95% confidence interval: 1.45–4.18]). Rates of 1-month survival with favorable neurologic outcome were 1% for infants, 2% for younger children, 2% for older children, and 11% for adolescents. CONCLUSION: Survival and favorable neurologic outcome at 1 month were more common after pediatric OHCAs than adult OHCAs.

Impact of transport to critical care medical centers on outcomes after out-of-hospital cardiac arrest ,

BACKGROUND Post-resuscitation care has emerged as an important predictor of survival from out-of-hospital cardiac arrest (OHCA). In Japan, selected hospitals are certified as Critical Care Medical Centers (CCMCs) based on their ability and expertise. HYPOTHESIS Outcome after OHCA is better in patients transported to a CCMC compared a non-critical care hospital (NCCH). MATERIALS AND METHODS Adults with OHCA of presumed cardiac etiology, treated by emergency medical services systems, and transported in Osaka from January 1, 2005 to December 31, 2007 were registered using a prospective Utstein style population cohort database. Primary outcome measure was 1 month neurologically favorable survival (CPC< or =2). Outcomes of patients transported to CCMC were compared with patients transported to NCCH using multiple logistic regressions and stratified on the basis of stratified field ROSC. RESULTS 10,383 cases were transported. Of these, 2881 were transported to CCMC and 7502 to NCCH. Neurologically favorable 1-month survival was greater in the CCMC group [6.7% versus 2.8%, P<0.001]. Among patients who were transported to hospital without field ROSC, neurologically favorable outcome was greater in the CCMC group than the NCCH group [1.7% versus 0.5%; adjusted odds ratio (OR), 3.39; 95% confidence interval (CI), 2.17-5.29; P<0.001]. In the presence of field ROSC, survival was similar between the groups [43% versus 41%; adjusted OR, 1.09; 95% CI, 0.82-1.45; P=0.554]. CONCLUSIONS Survival after OHCA of presumed cardiac etiology transported to CCMCs was better than those transported to NCCHs. For OHCA patients without field ROSC, transport to a CCMC was an independent predictor for a good neurological outcome.

Comparison of supraglottic airway versus endotracheal intubation for the pre-hospital treatment of out-of-hospital cardiac arrest

IntroductionBoth supraglottic airway devices (SGA) and endotracheal intubation (ETI) have been used by emergency life-saving technicians (ELST) in Japan to treat out-of-hospital cardiac arrests (OHCAs). Despite traditional emphasis on airway management during cardiac arrest, its impact on survival from OHCA and time dependent effectiveness remains unclear.MethodsAll adults with witnessed, non-traumatic OHCA, from 1 January 2005 to 31 December 2008, treated by the emergency medical services (EMS) with an advanced airway in Osaka, Japan were studied in a prospective Utstein-style population cohort database. The primary outcome measure was one-month survival with neurologically favorable outcome. The association between type of advanced airway (ETI/SGA), timing of device placement and neurological outcome was assessed by multiple logistic regression.ResultsOf 7,517 witnessed non-traumatic OHCAs, 5,377 cases were treated with advanced airways. Of these, 1,679 were ETI while 3,698 were SGA. Favorable neurological outcome was similar between ETI and SGA (3.6% versus 3.6%, P = 0.95). The time interval from collapse to ETI placement was significantly longer than for SGA (17.2 minutes versus 15.8 minutes, P < 0.001). From multivariate analysis, early placement of an advanced airway was significantly associated with better neurological outcome (Adjusted Odds Ratio (AOR) for one minute delay, 0.91, 95% confidence interval (CI) 0.88 to 0.95). ETI was not a significant predictor (AOR 0.71, 95% CI 0.39 to 1.30) but the presence of an ETI certified ELST (AOR, 1.86, 95% CI 1.04 to 3.34) was a significant predictor for favorable neurological outcome.ConclusionsThere was no difference in neurologically favorable outcome from witnessed OHCA for ETI versus SGA. Early airway management with advanced airway regardless of type and rhythm was associated with improved outcomes.

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.

Comparison of Emergency Medical Services Systems Across Pan-Asian Countries: A Web-based Survey

Abstract 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.

Age and sex analyses of out-of-hospital cardiac arrest in Osaka, Japan

OBJECTIVE To determine effective interventional targets for out-of-hospital cardiac arrests by analyzing the distribution characteristics of arrest patients according to age and sex with special emphasis on ventricular fibrillation (VF). METHODS All patients who suffered out-of-hospital cardiac arrest in Osaka Prefecture, Japan during 2 years, were prospectively recorded based on the Utstein style. The number and the incidence rate of cases of arrest, witnessed arrest, and witnessed VF were evaluated according to age and sex. The percentage of resuscitation attempts in arrest cases was also calculated. RESULTS We recorded 10139 consecutive out-of-hospital cardiac arrest cases. Resuscitation was attempted in 97.0% of 10139 and showed no significant differences by age and sex. The incidence rate of cardiac arrests increased exponentially with age. Men showed a significantly higher incidence rate of out-of-hospital arrests than women in every age group. Most of the witnessed VF cases showed cardiac a aetiology and were predominantly observed in men in their 50s, 60s and 70s. The incidence rates of witnessed VF were also greater in them. CONCLUSION Our study provides evidence that there are significant age and sex related epidemiological differences in cardiac arrests and we need to understand them better. Strategies that focus on high yielded patients, those in witnessed VF, should be pursued. These efforts should be expected to yield sex and age related differences in survivors.

Incidence and survival rate of bystander-witnessed out-of-hospital cardiac arrest with cardiac etiology in Osaka, Japan: a population-based study according to the Utstein style

PURPOSE To clarify the incidence and survival rate of bystander-witnessed out-of-hospital cardiac arrests (OHCA) with cardiac etiology in Osaka Prefecture, Japan, with a population of nearly 9 million according to the Utstein style. SUBJECTS AND METHODS 5047 consecutive OHCA cases were treated by ambulance personnel during the 12-month period starting since 1 May 1998. 974 cases were considered to be bystander-witnessed OHCA with cardiac etiology and analyzed using the Utstein style. RESULTS Of the 974 cases (100%), 50 cases (5.1%) survived after 1 month and 28 (2.9%) of them after 1 year. The Ventricular fibrillation (VF)/ventricular tachycardia (VT) group comprised 164 (16.8%) cases and there were statistically differences between the two groups as below (the VF/VT group vs. the non-VF/VT group): gender (male: 76.8 vs. 60.7%), age (61.7+/-14.7 vs. 68.7+/-17.1), history of ischemic heart disease (IHD) (30.5 vs. 15.3%), performance rate of bystander cardiopulmonary resuscitation (CPR) (34.1 vs. 21.4%) and time interval between receipt of an emergency call and arrival at the scene (5.5+/-2.9 vs. 6.0+/-2.9 min). CONCLUSION The incidence of bystander-witnessed (OHCA) with cardiac etiology and VF or VT were remarkably low compared with those reported by other studies conducted in some areas of Europe or the USA.

Reduction in incidence and fatality of out-of-hospital cardiac arrest in females of the reproductive age

AIMS The aim of this study was to determine relative risk (RR) of incidence and fatality of out-of-hospital cardiac arrest (OHCA) by gender and oestrogen status. METHODS AND RESULTS In a prospective, population-based observational study from 1998 through 2007, incidence and neurologically intact 1-month survival after OHCA were compared by gender after grouping: 0-12 years, 13-49 years, and > or =50 years according to menarche and menopause age. Among 26 940 cardiac arrests, there were 11 179 females and 15 701 males. Age-adjusted RR of females for OHCA incidence compared with males was 0.72 [95% confidence interval (CI), 0.58-0.91] in age 0-12 years, 0.39 (95% CI, 0.37-0.43) in age 13-49 years, and 0.54 (95% CI, 0.52-0.55) in age > or =50 years. Females aged 13-49 years had a significantly higher good neurological outcome than males [adjusted odds ratio (OR), 2.00 (95% CI 1.21-3.32)]. This sex difference was larger than that in the other age groups [adjusted OR, 0.82 (95% CI, 0.06-12.02) in age 0-12 years and 1.23 (95% CI, 0.98-1.54) in age > or =50 years]. CONCLUSION Reproductive females had a lower incidence and a better outcome of OHCA than females of other ages and males, which might be explained by cardioprotective effects of endogenous oestrogen on OHCA.