Public-Access Defibrillation and Out-of-Hospital Cardiac Arrest in Japan.

BACKGROUND: Early defibrillation plays a key role in improving survival in patients with out-of-hospital cardiac arrests due to ventricular fibrillation (ventricular-fibrillation cardiac arrests), and the use of publicly accessible automated external defibrillators (AEDs) can help to reduce the time to defibrillation for such patients. However, the effect of dissemination of public-access AEDs for ventricular-fibrillation cardiac arrest at the population level has not been extensively investigated. METHODS: From a nationwide, prospective, population-based registry of patients with out-of-hospital cardiac arrest in Japan, we identified patients from 2005 through 2013 with bystander-witnessed ventricular-fibrillation arrests of presumed cardiac origin in whom resuscitation was attempted. The primary outcome measure was survival at 1 month with a favorable neurologic outcome (Cerebral Performance Category of 1 or 2, on a scale from 1 [good cerebral performance] to 5 [death or brain death]). The number of patients in whom survival with a favorable neurologic outcome was attributable to public-access defibrillation was estimated. RESULTS: Of 43,762 patients with bystander-witnessed ventricular-fibrillation arrests of cardiac origin, 4499 (10.3%) received public-access defibrillation. The percentage of patients receiving public-access defibrillation increased from 1.1% in 2005 to 16.5% in 2013 (P<0.001 for trend). The percentage of patients who were alive at 1 month with a favorable neurologic outcome was significantly higher with public-access defibrillation than without public-access defibrillation (38.5% vs. 18.2%; adjusted odds ratio after propensity-score matching, 1.99; 95% confidence interval, 1.80 to 2.19). The estimated number of survivors in whom survival with a favorable neurologic outcome was attributed to public-access defibrillation increased from 6 in 2005 to 201 in 2013 (P<0.001 for trend). CONCLUSIONS: In Japan, increased use of public-access defibrillation by bystanders was associated with an increase in the number of survivors with a favorable neurologic outcome after out-of-hospital ventricular-fibrillation cardiac arrest.

Epidemiology of Out-of-Hospital Cardiac Arrest Due to Suffocation Focusing on Suffocation Due to Japanese Rice Cake: A Population-Based Observational Study From the Utstein Osaka Project.

BACKGROUND: Japanese rice cake ("mochi") is a major cause of food-choking accidents in Japan. However, the epidemiology of out-of-hospital cardiac arrests (OHCAs) due to suffocation caused by rice cakes is poorly understood. METHODS: OHCA data from 2005 to 2012 were obtained from the population-based OHCA registry in Osaka Prefecture. Patients aged ≥20 years who experienced OHCA caused by suffocation that occurred before the arrival of emergency-medical-service (EMS) personnel were included. Patient characteristics, prehospital interventions, and outcomes were compared based on the cause of suffocation (rice cake and non-rice-cake). The primary outcome was 1-month survival after OHCA. RESULTS: In total, 46 911 adult OHCAs were observed during the study period. Of the OHCAs, 7.0% (3,294/46,911) were due to suffocation, with choking due to rice cake as the cause in 9.5% of cases (314/3,294), and of these, 24.5% (77/314) occurred during the first 3 days of the New Year. In crude analysis, 1-month survival was 17.2% (54/314) in those with suffocation caused by rice cake and 13.4% (400/2,980) in those with suffocation due to other causes. In the multivariable analysis for all-cause suffocation, younger age, arrest witnessed by bystanders, and earlier EMS response time were significantly related to better 1-month survival. CONCLUSION: Approximately 10% of OHCAs due to suffocation were caused by rice-cake choking, and 25% of these occurred during the first 3 days of the New Year. Further efforts for establishing preventive measures as well as improving the early recognition of choking and encouraging bystanders to call EMS sooner are needed.

Cardiopulmonary resuscitation support application on a smartphone - randomized controlled trial.

BACKGROUND: This simulation trial aimed to compare the quality of cardiopulmonary resuscitation (CPR) with and without the newly-developed CPR support application on smartphones. METHODS AND RESULTS: In this trial, participants were randomly assigned to either the CPR support application group or the control group, stratified by sex and previous CPR training. Participants' CPR skills were evaluated by a 2-min case-based scenario test using the Leardal Resusci Anne PC Skill reporting Manikin System(®). The outcome measures were the proportion of chest compressions performed in each group and the number of total chest compressions and appropriate chest compressions performed during the 2-min test period. A total of 84 participants were enrolled and completed the protocol. All participants in the CPR support application group performed chest compressions, compared with only 31 (75.6%) in the control group (P<0.001). Among participants who performed chest compressions during the 2-min test period, the number of total chest compressions was significantly higher in the CPR support application group than in the control group (211.6±29.5 vs. 77.0±43.3, P<0.001). The number of appropriate chest compressions tended to be greater in the CPR support application group than in the control group, although it was statistically insignificant (30.3±57.3 vs. 17.2±28.7, P=0.246). CONCLUSIONS: In this cohort of laypersons, the newly-developed CPR support application for smartphones contributed to increasing the implementation rate and the number of total chest compressions performed and may assist in improving the survival rate for out-of-hospital cardiac arrests (UMIN000004740).

An association between systolic blood pressure and stroke among patients with impaired consciousness in out-of-hospital emergency settings.

BACKGROUND: Stroke is difficult to diagnose when consciousness is disturbed. However few reports have discussed the clinical predictors of stroke in out-of-hospital emergency settings. This study aims to evaluate the association between initial systolic blood pressure (SBP) value measured by emergency medical service (EMS) and diagnosis of stroke among impaired consciousness patients. METHODS: We included all patients aged 18 years or older who were treated and transported by EMS, and had impaired consciousness (Japan Coma Scale ≧ 1) in Osaka City (2.7 million), Japan from January 1, 1998 through December 31, 2007. Data were prospectively collected by EMS personnel using a study-specific case report form. Multiple logistic regressions assessed the relationship between initial SBP and stroke and its subtypes adjusted for possible confounding factors. RESULTS: During these 10 years, a total of 1,840,784 emergency patients who were treated and transported by EMS were documented during the study period in Osaka City. Out of 128,678 with impaired consciousness, 106,706 who had prehospital SBP measurements in the field were eligible for our analyses. The proportion of patients with severe impaired consciousness significantly increased from 14.5% in the <100 mmHg SBP group to 27.6% in the > =200 mmHg SBP group (P for trend <0.001). The occurrence of stroke significantly increased with increasing SBP (adjusted odd ratio [AOR] 1.34, 95% confidence interval [CI] 1.33 to 1.35), and the AOR of the SBP > =200 mmHg group versus the SBP 101-120 mmHg group was 5.26 (95% CI 4.93 to 5.60). The AOR of the SBP > =200 mmHg group versus the SBP 101-120 mmHg group was 9.76 in subarachnoid hemorrhage (SAH), 16.16 in intracranial hemorrhage (ICH), and 1.52 in ischemic stroke (IS), and the AOR of SAH and ICH was greater than that of IS. CONCLUSIONS: Elevated SBP among emergency patients with impaired consciousness in the field was associated with increased diagnosis of stroke.

Association between time-dependent changes in cerebrovascular autoregulation after cardiac arrest and outcomes: A prospective cohort study.

This prospective observational single-center cohort study aimed to determine an association between cerebrovascular autoregulation (CVAR) and outcomes in hypoxic-ischemic brain injury post-cardiac arrest (CA), and assessed 100 consecutive post-CA patients in Japan between June 2017 and May 2020 who experienced a return of spontaneous circulation. Continuous monitoring was performed for 96 h to determine CVAR presence. A moving Pearson correlation coefficient was calculated from the mean arterial pressure and cerebral regional oxygen saturation. The association between CVAR and outcomes was evaluated using the Cox proportional hazard model; non-CVAR time percent was the time-dependent, age-adjusted covariate. The non-linear effect of target temperature management (TTM) was assessed using a restricted cubic spline. Of the 100 participants, CVAR was detected using the cerebral performance category (CPC) in all patients with a good neurological outcome (CPC 1-2) and in 65 patients (88%) with a poor outcome (CPC 3-5). Survival probability decreased significantly with increasing non-CVAR time percent. The TTM versus the non-TTM group had a significantly lower probability of a poor neurological outcome at 6 months with a non-CVAR time of 18%-37% (p < 0.05). Longer non-CVAR time may be associated with significantly increased mortality in hypoxic-ischemic brain injury post-CA.

Impact of early intravenous epinephrine administration on outcomes following out-of-hospital cardiac arrest.

BACKGROUND: The effectiveness of epinephrine administration for cardiac arrests has been shown in animal models, but the clinical effect is still controversial. METHODS AND RESULTS: A prospective, population-based, observational study in Osaka involved consecutive out-of-hospital cardiac arrest (OHCA) patients from January 2007 through December 2009. We evaluated the outcomes among adult non-traumatic bystander-witnessed OHCA patients for whom the local protocol directed the emergency medical service personnel to administer epinephrine. After stratifying by first documented cardiac rhythm, outcomes were compared among the following groups: non-administration, ≤10, 11-20 and ≥21 min as the time from emergency call to epinephrine administration. A total of 3,161 patients were eligible for our analyses, among whom 1,013 (32.0%) actually received epinephrine. The epinephrine group had a significantly lower rate of neurologically intact 1-month survival than the non-epinephrine group (4.1% vs. 6.1%, P=0.028). In cases of ventricular fibrillation (VF) arrest, patients in the early epinephrine group who received epinephrine administration within 10 min had a significantly higher rate of neurologically intact 1-month survival compared with the non-epinephrine group (66.7% vs. 24.9%), though other epinephrine groups did not. In cases of non-VF arrest, the rate of neurologically intact 1-month survival was low, irrespective of epinephrine administration. CONCLUSIONS: The effectiveness of epinephrine after OHCA depends on the time of administration. When epinephrine is administered in the early phase, there is an improvement in neurological outcome from OHCA with VF.

Incidence and outcome of out-of-hospital cardiac arrest with public-access defibrillation. A descriptive epidemiological study in a large urban community.

BACKGROUND: Detailed characteristics of those who experience an out-of-hospital cardiac arrest (OHCA) with public-access defibrillation (PAD) are unknown. METHODS AND RESULTS: A prospective, population-based observational study involving consecutive OHCA patients with emergency responder resuscitation attempts was conducted from July 1, 2004 through December 31, 2008 in Osaka City. We extracted data for OHCA patients shocked by a public-access automated external defibrillator (AED) and evaluated the patients' and rescuers' characteristics. The main outcome measure was neurologically favorable 1-month survival. During the study period, 10,375 OHCA patients were registered and of 908 patients suffering ventricular fibrillation arrest, 53 (6%) received public-access AED shocks by lay-rescuers, with the proportion increasing from 0% in 2004 to 11% in 2008 (P for trend<0.001). Railway stations (34%) were the places where PAD shocks were most frequently delivered, followed by nursing homes (11%), medical facilities (9%), and fitness facilities (7%). In 57% of cases, the subject received public-access AED shocks delivered by non-medical persons, including employees of railway companies (13%), school teachers (6%), employees of fitness facilities (6%), and security guards (6%). The proportion of neurologically favorable 1-month survival tended to increase from 0% in 2005 to 58% in 2008 (P for trend=0.081). CONCLUSIONS: Railway stations are the most common places where shocks by public-access AEDs were delivered in large urban communities of Japan, and among lay-rescuers railway station workers use AEDs more frequently.

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

INTRODUCTION: Both 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. METHODS: All 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. RESULTS: Of 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. CONCLUSIONS: There 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.

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.

[Current situation and future scope of the cardiopulmonary cerebral resuscitation in Japan].

New guidelines for Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care (ECC) were released in October 2010. The 2010 Guidelines changed a core concept of basic life support from traditional A-B-C (Airway, Breathing, Chest compressions) procedure to C-A-B (Chest compressions, Airway, Breathing) procedure. In the change of concept, it is emphasized that rescuer should start CPR with chest compression immediately. Japanese researchers contributed to the revision of the guidelines from a stage of establishment of a CoSTR(2005 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science with Treatment Recommendations) which gives the guidelines theoretical evidences. It is expected for us to promote resuscitation science even in traditional theoretical field but also in the field of education, implementation, and team approach.

Pre-hospital portable monitoring of cerebral regional oxygen saturation (rSO2) by ambulance personnel during cardiopulmonary resuscitation: A prospective observational analysis of 87 cases in Osaka city, Japan.

BACKGROUND: Regional cerebral oxygen saturation (rSO2) is a non-invasive method of measuring cerebral perfusion; However, serial changes in cerebral rSO2 values among out-of-hospital cardiac arrest (OHCA) patients in pre-hospital settings have not been sufficiently investigated. We aimed to investigate the association between the serial change in rSO2 pattern and patient outcome. METHODS: We evaluated rSO2 in OHCA patients using portable monitoring by emergency life-saving technicians (ELTs) from June 2013 to December 2019 in Osaka City, Japan. We divided the patterns of serial of rSO2 change into type 1 (increasing pattern) and type 2 (non-increasing pattern). Patients in whom measurement started after return of spontaneous circulation (ROSC) were excluded. The outcome measures were 'Prehospital ROSC', 'Alive at admission', '1-month survival' and 'Cerebral Performance Category (CPC) 1 or 2'. RESULTS: Eighty-seven patients were eligible for this analysis (type 1: n = 40, median age: 80.5 [IQR: 72-85.5] years, male: n = 20 [50.0%]; type 2: n = 47, 81 [72-85.5] years, male: n = 28 [59.6%]). In a multivariable logistic regression adjusted for confounding factors, outcomes of 'Prehospital ROSC' and 'Alive at admission' were significantly higher in type 1 than type 2 pattern (11/40 [27.5%] vs. 2/47 [4.26%], AOR 5.67, 95% CI 1.04-30.96, p < 0.045 and 17/40 [42.5%] vs. 6/41 [12.8%], AOR 3.56, 95% CI 1.11-11.43, p < 0.033). There was no significant difference in '1-month survival' and 'CPC 1 or 2' between patterns. CONCLUSION: Type 1 (increasing pattern) was associated with 'Prehospital ROSC' and 'Alive at admission'. Pre-hospital monitoring of cerebral rSO2 might lead to a new resuscitation strategy.

Usefulness of simultaneous measurement of brain and muscle regional oxygen saturation in shock patients: A report of three cases.

The regional oxygen saturation (rSO2) values of brain and muscle tissues can be measured simultaneously even if blood pressure cannot be measured due to circulatory failure associated with shock and may continuously reflect the oxygen supply-demand balance.

Dynamic changes of the hemoglobin index during resuscitation in patients with out-of-hospital cardiopulmonary arrest due to freshwater drowning: A retrospective observational study.

BACKGROUND: The hemoglobin index (HbI) represents the amount of hemoglobin, which reflects the regional tissue blood volume. The HbI is calculated by a regional oxygen saturation monitor. In freshwater drowning, inhaled water is immediately absorbed into the blood causing hemodilution. We hypothesized that this blood dilution could be observed in real time using HbI values in patients with out-of-hospital cardiac arrest (OHCA) due to freshwater drowning. METHODS: In this single-center retrospective, observational study, we examined the HbI in patients with OHCA due to freshwater drowning from April 2015 to May 2020. Patients with OHCA due to hanging were selected as a control group. RESULTS: Thirty-two patients in the freshwater drowning group and 21 in the control group were eligible for inclusion. In the freshwater drowning group, the HbI values in the return of spontaneous circulation (ROSC) group were significantly decreased in comparison to the non-ROSC group (-0.28 [IQR -0.55, -0.12] vs. -0.04 [IQR -0.16, 0.025]; p = 0.024). In the control group, the change of HbI during resuscitation in the ROSC and non-ROSC groups was not significantly different (0.11 [IQR -0.3525, 0.4225] vs. -0.02 [IQR -0.14, 0.605]; p = 0.8228). In each patient with ROSC in the freshwater drowning group, the HbI value after ROSC was significantly decreased in comparison to before ROSC (1.2±0.5 vs. 0.9±0.5]; p = 0.0156). In contrast, this difference was not observed in patients with an ROSC in the control group (3.7±1.3 vs. 3.8±1.4]; p = 0.7940). CONCLUSION: Blood dilution induced by freshwater drowning might be detected in real time using the HbI. To prove the validity of this research's result, further prospective large study is needed.

Effectiveness of near-infrared spectroscopy-guided continuous chest compression resuscitation without rhythm check in patients with out-of-hospital cardiac arrest: The prospective multicenter TripleCPR 16 study.

BACKGROUND: The proportion of adult patients with return of spontaneous circulation (ROSC) following out-of-hospital cardiac arrest (OHCA) remains unchanged since 2012. A better resuscitation strategy is needed. This study evaluated the effectiveness of a regional cerebral oxygen saturation (rSO2)-guided resuscitation protocol without rhythm check based on our previous study. METHODS: Because defibrillation is the definitive therapy that should be performed without delay for shockable rhythm, the study subjects were OHCA patients with non-shockable rhythm on hospital arrival at three emergency departments. They were divided into three groups based on their baseline rSO2 value (%): ≥50, ≥40 to <50, or <40. Continuous chest compression without rhythm checks was performed for 16 minutes or until a maximum increase in rSO2 of 10%, 20%, or 35% was achieved in each group, respectively. This intervention cohort was compared with a historical control cohort regarding the probability of ROSC using inverse probability of treatment weighting (IPTW) with propensity score. RESULTS: The control and intervention cohorts respectively included 86 and 225 patients. The rate of ROSC was not significantly different between the groups (adjusted OR 0.91 [95% CI, 0.64-1.29], P = 0.60), but no serious adverse events occurred. Sensitivity analyses 1 and 2 showed a significant difference or positive tendency for higher probability of ROSC (adjusted OR 1.63 [95% CI, 1.22-2.17], P < 0.001) (adjusted OR 1.25 [95% CI, 0.95-1.63], P = 0.11). CONCLUSIONS: This trial suggested that a new cardiopulmonary resuscitation protocol with different rhythm check timing could be created using the rSO2 value. Clinical trial number: UMIN000025684.

Effectiveness of the hemoglobin index for screening of subarachnoid hemorrhage in out-of-hospital cardiopulmonary arrest patients: a retrospective observational study.

AIM: The hemoglobin index (HbI) represents the amount of hemoglobin, which reflects regional tissue blood volume. The HbI is calculated in real time by a regional oxygen saturation (rSO 2) monitor. For the hypothesis of our HbI project, we theorized that HbI could be a new method for the screening of subarachnoid hemorrhage (SAH) in overcrowded emergency departments. As a first step, this study aimed to clarify the effectiveness of HbI in screening SAH in out-of-hospital cardiopulmonary arrest (OHCA) patients using the rSO 2 data of our previous studies. METHODS: In this single-center, retrospective, observational study, we examined HbI in patients with OHCA transferred to the Trauma and Acute Critical Care Center at Osaka University Hospital (Osaka, Japan) during the period between April 2013 and December 2015. A sensor attached to the patient's forehead monitored HbI continuously. RESULTS: Among 63 patients (40 men and 23 women; mean age, 76 [interquartile range (IQR), 66-85] years) with OHCA, five were diagnosed as having SAH (SAH group) and 58 were not (non-SAH group). The HbI values were significantly higher in the SAH group than in the non-SAH group (1.35 [IQR: 0.80-2.69] versus 0.41 [IQR: 0.32-0.61]), P = 0.0042). In the SAH group, with an HbI cut-off value of 1.18, the specificity and sensitivity were 96% and 80%, respectively, and the area under the receiver operating characteristic curve of HbI was 0.89. CONCLUSIONS: The HbI might be useful for the screening of SAH in patients with OHCA. The application of HbI in the emergency department could be expected in the future.

A follow-up report on the effect of a simplified basic life support training program for non-medical staff working at a university hospital: changes in attitude toward cardiopulmonary resuscitation and automated external defibrillator use through repeat training.

AIM: This study aimed to investigate the effect of repeat training and the interval of reattending a simplified basic life support (BLS) training course. METHODS: We administered a questionnaire on the attitude toward cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use (check for response, chest compression, and using an AED) before and immediately after a 45-min BLS training program provided for non-medical staff working at a university hospital from September 2010 to November 2018. The main outcome was positive willingness of the participants toward CPR and AED use. The effect of repeat training was assessed with McNemar's test and multivariable logistic regression analysis. Differences in the interval of reattending the simplified BLS training course were assessed with Fisher's exact test. RESULTS: Fifty-nine training courses were held. Among the total participant count of 1,025, 760 individuals attended, of whom 126 attended the training multiple times. The proportion of participants showing a positive attitude toward chest compression before the course increased as the number of attendances increased (adjusted odds ratio 1.62: 9.8% at first training to 58.8% at sixth training). The positive attitude of participants before the course was significantly greater when the training interval was <1 year (36.1% versus 18.7%). There was no significant difference for a 6-month interval (40% versus 23.2%). CONCLUSIONS: Repeat training for non-medical staff in a chest compression-only CPR training course showed a cumulative effect of repeat attendance. A course interval of <1 year from the previous attendance would be important for maintaining a positive attitude toward CPR and AED use.

Community-Wide Dissemination of Bystander Cardiopulmonary Resuscitation and Automated External Defibrillator Use Using a 45-Minute Chest Compression-Only Cardiopulmonary Resuscitation Training.

Background Little is known about whether cardiopulmonary resuscitation ( CPR ) training can increase bystander CPR in the community or the appropriate target number of CPR trainings. Herein, we aimed to demonstrate community-wide aggressive dissemination of CPR training and evaluate temporal trends in bystander CPR . Methods and Results We provided CPR training (45-minute chest compression-only CPR plus automated external defibrillator use training or the conventional CPR training), targeting 16% of residents. All emergency medical service-treated out-of-hospital cardiac arrests of medical origin were included. Data on patients experiencing out-of-hospital cardiac arrest and bystander CPR quality were prospectively collected from September 2010 to December 2015. The primary outcome was the proportion of high-quality bystander CPR . During the study period, 57 173 residents (14.7%) completed the chest compression-only CPR training and 32 423 (8.3%) completed conventional CPR training. The proportion of bystander CPR performed did not change (from 43.3% in 2010 to 42.0% in 2015; P for trend=0.915), but the proportion of high-quality bystander CPR delivery increased from 11.7% in 2010 to 20.7% in 2015 ( P for trend=0.015). The 1-year increment was associated with high-quality bystander CPR (adjusted odds ratio, 1.461; 95% CI, 1.055-2.024). Bystanders who previously experienced CPR training were 3.432 times (95% CI, 1.170-10.071) more likely to perform high-quality CPR than those who did not. Conclusions We trained 23.0% of the residents in the medium-sized city of Osaka, Japan, and demonstrated that the proportion of high-quality CPR performed on the scene increased gradually, whereas that of bystander CPR delivered overall remained stable.

Public-access AED pad application and outcomes for out-of-hospital cardiac arrests in Osaka, Japan.

BACKGROUND: Actual application of public-access automated external defibrillator (AED) pads to patients with an out-of-hospital cardiac arrest (OHCA) by the public has been poorly investigated. METHODS: AED applications, prehospital characteristics, and one-month outcomes of OHCAs occurring in Osaka Prefecture from 2011 to 2012 were obtained from the Utstein Osaka Project registry. Patients with a non-traumatic OHCA occurring before emergency medical service attendance were enrolled. The proportion of AED pads that were applied to the patients' chests by the public and one-month outcomes were analysed according to the location of OHCA. RESULTS: In total, public-access AED pads were applied to 3.5% of OHCA patients (351/9978) during the study period. In the multivariate analyses, OHCAs that occurred in public places and received bystander-initiated cardiopulmonary resuscitation were associated with significantly higher application of public-access AEDs. Among the patients for whom public-access AED pads were applied, 29.6% (104/351) received public-access defibrillation. One-month survival with a favourable neurological outcome was significantly higher among patients who had an AED applied compared to those who did not (19.4% vs. 3.0%; OR: 2.76 [95% CI: 1.92-3.97]). CONCLUSION: The application of public-access AEDs leads to favourable outcomes after an OHCA, but utilisation of available equipment remains insufficient, and varies considerably according to the location of the OHCA event. Alongside disseminating public-access AEDs, further strategic approaches for the deployment of AEDs at the scene, as well as basic life support training for the public are required to improve survival rates after OHCAs.

Low Level of TSST-1 Antibody in Burn Patients With Toxic Shock Syndrome Caused by Methicillin-Resistant Staphylococcus aureus.

Toxic shock syndrome (TSS) caused by methicillin-resistant Staphylococcus aureus (MRSA) nosocomial infection is a growing concern in both adult and pediatric patients. The reason why TSS appears in only some patients with MRSA infection remains unclear. In this study, we analyzed serial TSS toxin-1 (TSST-1) antibody in patients with burn injury to investigate the mechanisms of TSS caused by MRSA nosocomial infection. This study comprised of patients with burn injury in our burn care unit from September, 2010 to August, 2011. Serum samples were collected serially on admission, at 48 to 72 hours after injury, on the day MRSA infection appeared, and on the day MRSA infection resolved. TSST-1 antibody was measured by enzyme-linked immunosorbent assay (ELISA). TSS was diagnosed according to the criteria of the Centers for Disease Control. Serial serum samples were collected from 24 patients and nosocomial MRSA infection was detected in 12 patients. In these 12 patients, TSS occurred in five patients (TSS+ group) but did not occur in the other seven patients (TSS- group). TSST-1 antibody level was significantly lower in the TSS+ group than TSS- group on admission and on the day MRSA infection appeared. All patients in the TSS+ group received intravenous immune globulin when TSS was diagnosed, and no patients died of TSS. Patients suffering from TSS had a lower level of TSST-1 antibody than patients not suffering from TSS. Testing for TSST-1 antibody in the clinical setting might help to predict and prevent the appearance of TSS caused by nosocomial MRSA infection.

Dispatcher instruction of chest compression-only CPR increases actual provision of bystander CPR.

BACKGROUND: A preceding randomized controlled trial demonstrated that chest compression-only cardiopulmonary resuscitation (CPR) instruction by dispatcher was more effective to increase bystander CPR than conventional CPR instruction. However, the actual condition of implementation of each type of dispatcher instruction (chest compression-only CPR [CCCPR] or conventional CPR with rescue breathing) and provision of bystander CPR in real prehospital settings has not been sufficiently investigated. METHODS: This registry prospectively enrolled patients aged =>18 years suffering an out-of-hospital cardiac arrest (OHCA) of non-traumatic causes before emergency-medical-service (EMS) arrival, who were considered as target subjects of dispatcher instruction, resuscitated by EMS personnel, and transported to medical institutions in Osaka, Japan from January 2005 through December 2012. The primary outcome measure was provision of CPR by a bystander. Multiple logistic regression analysis was used to assess factors that were potentially associated with provision of bystander CPR. RESULTS: Among 37,283 target subjects of dispatcher instruction, 5743 received CCCPR instruction and 13,926 received conventional CPR instruction. The proportion of CCCPR instruction increased from 5.7% in 2005 to 25.6% in 2012 (p for trend <0.001). The CCCPR instruction group received bystander CPR more frequently than conventional CPR instruction group (70.0% versus 62.1%, p<0.001). In the multivariable analysis, CCCPR dispatcher instruction was significantly associated with provision of bystander CPR compared with conventional CPR instruction (adjusted odds ratio 1.44, 95% CI 1.34-1.55). CONCLUSIONS: CCCPR dispatcher instruction among adult OHCA patients significantly increased the actual provision of bystander CPR.