Takahisa Kamikura

Do early emergency calls before patient collapse improve survival after out-of-hospital cardiac arrests?

AIM Some out-of-hospital cardiac arrests (OHCAs) are witnessed after emergency calls. This study aimed to confirm the benefit of early emergency calls before patient collapse on survival after OHCAs witnessed by bystanders and/or emergency medical technicians (EMTs). METHODS We analysed 278,310 witnessed OHCAs [EMT-witnessed cases (n=54,172), bystander-witnessed cases (n=224,138)] without pre-hospital physician involvement from all Japanese OHCA data prospectively collected between 2006 and 2012. The data were analysed for the correlation between neurologically favourable 1-month survival and the time interval between the emergency call and patient collapse. RESULTS When emergency calls were placed earlier before patient collapse, the proportion of EMT-witnessed cases and survival rate after OHCAs witnessed by bystanders and EMTs were higher. When analysed only for bystander-witnessed cases, for earlier emergency calls placed before patient collapse, survival rate and incidences of bystander cardiopulmonary resuscitation (CPR) and dispatcher-assisted CPR decreased: 2.9%, 33.6% and 24.4%, respectively, for emergency calls placed >6min before collapse and 5.5%, 48.8% and 48.5%, respectively, for those placed 1-2min after collapse. Multivariable logistic regression showed that call-to-collapse interval (adjusted odds ratio; 95% confidence interval) (0.92; 0.90-0.94) and EMT response time after collapse (0.84; 0.82-0.86) were associated with survival after bystander-witnessed OHCAs with emergency calls before collapse. CONCLUSION Early emergency calls before patient collapse efficiently increases the proportion of EMT-witnessed cases and promotes survival after witnessed OHCAs. However, early emergency call before collapse may worsen the outcome when the patients condition deteriorates to cardiac arrest before EMT arrival.

Improper bystander-performed basic life support in cardiac arrests managed with public automated external defibrillators

AIM The aim of the study was to determine the quality of basic life support (BLS) in out-of-hospital cardiac arrests (OHCAs) receiving bystander cardiopulmonary resuscitation (CPR) and public automated external defibrillator (AED) application. METHODS From January 2006 to December 2012, data were prospectively collected from OHCA) and impending cardiac arrests treated with and without public AED before emergency medical technician (EMT) arrival. Basic life support actions and outcomes were compared between cases with and without public AED application. Interruptions of CPR were compared between 2 groups of AED users: health care provider (HCP) and non-HCP. RESULTS Public AEDs were applied in 10 and 273 cases of impending cardiac arrest and non-EMT-witnessed OHCAs, respectively (4.3% of 6407 non-EMT-witnessed OHCAs). Defibrillation was delivered to 33 (13.3%) cases. Public AED application significantly improved the rate of 1-year neurologically favorable survival in bystander CPR-performed cases with shockable initial rhythm but not in those with nonshockable rhythm. Emergency calls were significantly delayed compared with other OHCAs without public AED application (median: 3 and 2 minutes, respectively; P < .0001). Analysis of AED records obtained from 136 (54.6%) of the 249 cases with AED application revealed significantly lower rate of compressions delivered per minute and significantly greater proportion of CPR pause in the non-HCP group. Time interval between power on and the first electrocardiographic analysis widely varied in both groups and was significantly prolonged in the non-HCP group (P = .0137). CONCLUSIONS Improper BLS responses were common in OHCAs treated with public AEDs. Periodic training for proper BLS is necessary for both HCPs and non-HCPs.

Potential association of bystander-patient relationship with bystander response and patient survival in daytime out-of-hospital cardiac arrest.

AIM To investigate whether the bystander-patient relationship affects bystander response to out-of-hospital cardiac arrest (OHCA) and patient outcomes depending on the time of day. METHODS This population-based observational study in Japan involving 139,265 bystander-witnessed OHCAs (90,426 family members, 10,479 friends/colleagues, and 38,360 others) without prehospital physician involvement was conducted from 2005 to 2009. Factors associated with better bystander response [early emergency call and bystander cardiopulmonary resuscitation (BCPR)] and 1-month neurologically favourable survival were assessed. RESULTS The rates of dispatcher-assisted CPR during daytime (7:00-18:59) and nighttime (19:00-6:59) were highest in family members (45.6% and 46.1%, respectively, for family members; 28.7% and 29.2%, respectively, for friends/colleagues; and 28.1% and 25.3%, respectively, for others). However, the BCPR rates were lowest in family members (35.5% and 37.8%, respectively, for family members; 43.7% and 37.8%, respectively, for friends/colleagues; and 59.3% and 50.0%, respectively, for others). Large delays (≥ 5 min) in placing emergency calls and initiating BCPR were most frequent in family members. The overall survival rate was lowest (2.7%) for family members and highest (9.1%) for friends/colleagues during daytime. Logistic regression analysis revealed that the effect of bystander relationship on survival was significant only during daytime [adjusted odds ratios (95% CI) for survival from daytime OHCAs with family as reference were 1.51 (1.36-1.68) for friends/colleagues and 1.23 (1.13-1.34) for others]. CONCLUSIONS Family members are least likely to perform BCPR and OHCAs witnessed by family members are least likely to survive during daytime. Different strategies are required for family-witnessed OHCAs.

Impact of bystander-performed ventilation on functional outcomes after cardiac arrest and factors associated with ventilation-only cardiopulmonary resuscitation: A large observational study

AIM To determine the effectiveness of ventilations in bystander cardiopulmonary resuscitation (BCPR) and to identify the factors associated with ventilation-only BCPR. METHODS From out-of-hospital cardiac arrest (OHCA) data prospectively collected from 2005 to 2011 in Japan, we extracted data for 210,134 bystander-witnessed OHCAs with complete datasets but no prehospital involvement of physician [no BCPR, 115,733; ventilation-only, 2093; compression-only, 61,075; and conventional (compressions+ventilations) BCPR, 31,233] and determined the factors associated with 1-month neurologically favourable survival using simple and multivariable logistic regression analyses. In 91,885 patients with known BCPR durations, we determined the factors associated with ventilation-only BCPR. RESULTS The rate of survival in the no BCPR, ventilation-only, compression-only and conventional group was 2.8%, 3.9%, 4.5% and 5.0%, respectively. After adjustment for other factors associated with outcomes, the survival rate in the ventilation-only group was higher than that in the no BCPR group (adjusted OR; 95% CI, 1.29; 1.01-1.63), but lower than that in the compression-only (0.76; 0.59-0.96) or conventional groups (0.70; 0.55-0.89). Conventional CPR had the highest OR for survival in almost all OHCA subgroups. The adjusted OR (95% CI) for survival after dividing BCPR into ventilation and compression components was 1.19 (1.11-1.27) and 1.60 (1.51-1.69), respectively. Older guidelines, female sex, younger patient age, bystander-initiated CPR without instruction, early BCPR and short BCPR duration were associated with ventilation-only BCPR. CONCLUSIONS Ventilation is a significant component of BCPR, but alone is less effective than compression in improving neurologically favourable survival after OHCAs.

Are regional variations in activity of dispatcher-assisted cardiopulmonary resuscitation associated with out-of-hospital cardiac arrests outcomes? A nation-wide population-based cohort study

AIM Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) impacts the rates of bystander CPR (BCPR) and survival after out-of-hospital cardiac arrests (OHCAs). This study aimed to elucidate whether regional variations in indexes for BCPR and emergency medical service (EMS) may be associated with OHCA outcomes. METHODS We conducted a population-based observational study involving 157,093 bystander-witnessed, resuscitation-attempted OHCAs without physician involvement between 2007 and 2011. For each index of BCPR and EMS, we classified the 47 prefectures into the following three groups: advanced, intermediate, and developing regions. Nominal logit analysis followed by multivariable logistic regression including OHCA backgrounds was employed to examine the association between neurologically favourable 1-month survival, and regional classifications based on BCPR- and EMS-related indexes. RESULTS Logit analysis including all regional classifications revealed that the number of BLS training course participants per population or bystanders own performance of BCPR without DA-CPR was not associated with the survival. Multivariable logistic regression including the OHCA backgrounds known to be associated with survival (BCPR provision, arrest aetiology, initial rhythm, patient age, time intervals of witness-to-call and call-to-arrival at patient), the following regional classifications based on DA-CPR but not on EMS were associated with survival: sensitivity of DA-CPR [adjusted odds ratio (95% confidence intervals) for advanced region; those for intermediate region, with developing region as reference, 1.277 (1.131-1.441); 1.162 (1.058-1.277)]; the proportion of bystanders to follow DA-CPR [1.749 (1.554-1.967); 1.280 (1.188-1.380)]. CONCLUSIONS Good outcomes of bystander-witnessed OHCAs correlate with regions having higher sensitivity of DA-CPR and larger proportion of bystanders to follow DA-CPR.

Advantage of CPR-first over call-first actions for out-of-hospital cardiac arrests in nonelderly patients and of noncardiac aetiology

AIM To assess the benefit of immediate call or cardiopulmonary resuscitation (CPR) for survival from out-of-hospital cardiac arrests (OHCAs). METHODS Of 952,288 OHCAs in 2005-2012, 41,734 were bystander-witnessed cases without prehospital involvement of physicians but with bystander CPR (BCPR) on bystanders own initiative. From those OHCAs, we finally extracted the following three call/BCPR groups: immediate Call+CPR (N=10,195, emergency call/BCPR initiated at 0 or 1 min after witness, absolute call-BCPR time interval=0 or 1 min), immediate Call-First (N=1820, emergency call placed at 0 or 1 min after witness, call-to-BCPR interval=2-4 min), immediate CPR-First (N=5446, BCPR initiated at 0 or 1 min after witness, BCPR-to-call interval=2-4 min). One-month neurologically favourable survivals were compared among the groups. Critical comparisons between Call-First and CPR-First groups were made considering arrest aetiology, age, and bystander-patient relationship after confirming the interactions among variables. RESULTS The overall survival rates in immediate Call+CPR, Call-First, and CPR-First groups were 11.5, 12.4, and 11.5%, respectively without significant differences (p=0.543). Subgroup analyses by multivariate logistic regression following univariate analysis disclosed that CPR-first group is more likely to survive in subgroups of noncardiac aetiology (adjusted odds ratio; 95% confidence interval, 2.01; 1.39-2.98) and of nonelderly OHCAs (1.38; 1.09-1.76). CONCLUSIONS Immediate CPR-first action followed by an emergency call without a large delay may be recommended when a bystander with sufficient skills to perform CPR witnesses OHCAs in nonelderly people and of noncardiac aetiology.

Recruitments of trained citizen volunteering for conventional cardiopulmonary resuscitation are necessary to improve the outcome after out-of-hospital cardiac arrests in remote time-distance area: A nationwide population-based study

AIMS To compare the factors associated with survival after out-of-hospital cardiac arrests (OHCAs) among three time-distance areas (defined as interquartile range of time for emergency medical services response to patients side). METHODS From a nationwide, prospectively collected data on 716,608 OHCAs between 2007 and 2012, this study analyzed 193,914 bystander-witnessed OHCAs without pre-hospital physician involvement. RESULTS Overall neurologically favourable 1-month survival rates were 7.4%, 4.1% and 1.7% for close, intermediate and remote areas, respectively. We classified BCPR by type (compression-only vs. conventional) and by dispatcher-assisted CPR (DA-CPR) (with vs. without); the effects on time-distance area survival were analyzed by BCPR classification. Association of each BCPR classification with survival was affected by time-distance area and arrest aetiology (p<0.05). The survival rates in the remote area were much higher with conventional BCPR than with compression-only BCPR (odds ratio; 95% confidence interval, 1.26; 1.05-1.51) and with BCPR without DA-CPR than with BCPR with DA-CPR (1.54; 1.29-1.82). Accordingly, we classified BCPR into five groups (no BCPR, compression-only with DA-CPR, conventional with DA-CPR, compression-only without DA-CPR, and conventional without DA-CPR) and analyzed for associations with survival, both cardiac and non-cardiac related, in each time-distance area by multivariate logistic regression analysis. In the remote area, conventional BCPR without DA-CPR significantly improved survival after OHCAs of cardiac aetiology, compared with all the other BCPR groups. Other correctable factors associated with survival were short collapse-to-call and call-to-first CPR intervals. CONCLUSION Every effort to recruit trained citizens initiating conventional BCPR should be made in remote time-distance areas.

Misplaced links in the chain of survival due to an incorrect manual for the emergency call at public facilities

BackgroundThe incidence of delayed emergency calls and the outcome of out-of-hospital cardiac arrest (OHCA) may differ among public facilities when emergency calls are placed by institutional staff. The purpose of this study was to identify the actions prescribed in the rules and/or manuals of public facilities and to clarify whether the incidence of delayed emergency call placement and the outcome of OHCA differ among these facilities.MethodsWe performed a questionnaire-based survey regarding emergency calls in public facilities in our community and analyzed our regional Utstein-based OHCA database.ResultsOur questionnaire survey disclosed that the most common actions prescribed in the manuals or rules applied in care facilities and educational institutions are to report the situation when a cardiac arrest occurs and to follow the directions of a custodian or supervisor. The international web search disclosed that these actions are rarely prescribed in medical emergency manuals in other countries. Most of these manuals simply say that staff should make an emergency call immediately upon detecting a serious illness or medical emergency. Analysis of the Utstein-based database from our community revealed that the time interval between collapse and emergency call placement is prolonged and the outcome of cardiac arrest poor in care facilities. A prompt emergency call and cardiopulmonary resuscitation (CPR) after arrest are associated with improved 1-year survival following OHCA. Contrary to accepted wisdom, staff who recognize a cardiac arrest may consult their supervisor and then continue CPR until they receive instructions from him or her.ConclusionsManuals or rules for making emergency calls in our public facilities may contain incorrect information, and emergency calls may be delayed owing to correctable human factors. Such manuals should be checked and revised.

Effects of obligatory training and prior training experience on attitudes towards performing basic life support: a questionnaire survey

To determine the effect of Japanese obligatory basic life support training for new drivers license applicants on their willingness to carry out basic life support.