Taiki Nishi

Factors associated with quality of bystander CPR: The presence of multiple rescuers and bystander-initiated CPR without instruction

AIMS To identify the factors associated with good-quality bystander cardiopulmonary resuscitation (BCPR). METHODS Data were prospectively collected from 553 out-of-hospital cardiac arrests (OHCAs) managed with BCPR in the absence of emergency medical technicians (EMT) during 2012. The quality of BCPR was evaluated by EMTs at the scene and was assessed according to the standard recommendations for chest compressions, including proper hand positions, rates and depths. RESULTS Good-quality BCPR was more frequently confirmed in OHCAs that occurred in the central/urban region (56.3% [251/446] vs. 39.3% [42/107], p=0.0015), had multiple rescuers (31.8% [142/446] vs. 11.2% [12/107], p<0.0001) and received bystander-initiated BCPR (22.0% [98/446] vs. 5.6% [6/107], p<0.0001). Good-quality BCPR was less frequently performed by family members (46.9% [209/446] vs. 67.3% [72/107], p=0.0001), elderly bystanders (13.5% [60/446] vs. 28.0% [30/107], p=0.0005) and in at-home OHCAs (51.1% [228/446] vs. 72.9% [78/107], p<0.0001). BCPR duration was significantly longer in the good-quality group (median, 8 vs. 6min, p=0.0015). Multiple logistic regression analysis indicated that multiple rescuers (odds ratio=2.8, 95% CI 1.5-5.6), bystander-initiated BCPR (2.7, 1.1-7.3), non-elderly bystanders (1.9, 1.1-3.2), occurrence in the central region (2.1, 1.3-3.3) and duration of BCPR (1.1, 1.0-1.1) were associated with good-quality BCPR. Moreover, good-quality BCPR was initiated earlier after recognition/witness of cardiac arrest compared with poor-quality BCPR (3 vs. 4min, p=0.0052). The rate of neurologically favourable survival at one year was 2.7 and 0% in the good-quality and poor-quality groups, respectively (p=0.1357). CONCLUSIONS The presence of multiple rescuers and bystander-initiated CPR are predominantly associated with good-quality BCPR.

Survey of a Protocol to Increase Appropriate Implementation of Dispatcher-Assisted Cardiopulmonary Resuscitation for Out-of-Hospital Cardiac Arrest

Background— Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) attempts to improve the management of out-of-hospital cardiac arrest by laypersons who are unable to recognize cardiac arrest and are unfamiliar with CPR. Therefore, we investigated the sensitivity and specificity of our new DA-CPR protocol for achieving implementation of bystander CPR in out-of-hospital cardiac arrest victims not already receiving bystander CPR. Methods and Results— Since 2007, we have applied a new DA-CPR protocol that uses supplementary key words. Fire departments prospectively collected baseline data on DA-CPR from January 2009 to December 2011. DA-CPR was attempted in 2747 patients; of these, 417 (15.2%) did not experience cardiac arrest. The sensitivity and specificity of the 2007 protocol versus estimated values of the previous standard protocol were 72.9% versus 50.3% and 99.6% versus 99.8%, respectively. We identified key words that may be useful for detecting out-of-hospital cardiac arrest. Multiple logistic regression analysis revealed that the occurrence of cardiac arrest after an emergency call (odds ratio, 16.85) and placing an emergency call away from the scene of the arrest (odds ratio, 11.04) were potentially associated with failure to provide DA-CPR. Furthermore, at-home cardiac arrest (odds ratio, 1.61) and family members as bystanders (odds ratio, 1.55) were associated with bystander noncompliance with DA-CPR. No complications were reported in the 417 patients who received DA-CPR but did not have cardiac arrest. Conclusions— Our 2007 protocol is safe and highly specific and may be more sensitive than the standard protocol. Understanding the factors associated with failure of bystanders to provide DA-CPR and implementing public education are necessary to increase the benefit of DA-CPR.

Does the number of rescuers affect the survival rate from out-of-hospital cardiac arrests? Two or more rescuers are not always better than one ☆

REVIEW An increased number of rescuers may improve the survival rate from out-of-hospital cardiac arrests (OHCAs). The majority of OHCAs occur at home and are handled by family members. MATERIALS AND METHODS Data from 5078 OHCAs that were witnessed by citizens and unwitnessed by citizens or emergency medical technicians from January 2004 to March 2010 were prospectively collected. The number of rescuers was identified in 4338 OHCAs and was classified into two (single rescuer (N=2468) and multiple rescuers (N=1870)) or three (single rescuer, two rescuers (N=887) and three or more rescuers (N=983)) groups. The backgrounds, characteristics and outcomes of OHCAs were compared between the two groups and among the three groups. RESULTS When all OHCAs were collectively analysed, an increased number of rescuers was associated with better outcomes (one-year survival and one-year survival with favourable neurological outcomes were 3.1% and 1.9% for single rescuers, 4.1% and 2.0% for two rescuers, and 6.0% and 4.6% for three or more rescuers, respectively (p=0.0006 and p<0.0001)). A multiple logistic regression analysis showed that the presence of multiple rescuers is an independent factor that is associated with one-year survival (odds ratio (95% confidence interval): 1.539 (1.088-2.183)). When only OHCAs that occurred at home were analysed (N=2902), the OHCAs that were handled by multiple rescuers were associated with higher incidences of bystander CPR but were not associated with better outcomes. CONCLUSIONS In summary, an increased number of rescuers improves the outcomes of OHCAs. However, this beneficial effect is absent in OHCAs that occur at home.

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.

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.

Primary respiratory arrest recognised by emergency medical technicians and followed by cardiac arrest in Japan: Identification of a subgroup of EMT-witnessed cardiac arrests with an extremely poor outcome

REVIEW Some unconscious patients are found to be in primary respiratory arrest (PRA) by emergency medical technicians (EMTs). In contrast to citizens, EMTs manage PRA with artificial ventilation but not with cardiopulmonary resuscitation (CPR). This study aimed to investigate the characteristics and outcomes of PRA prior to EMT arrival and compare these data with those of a PRA-related group: patients with out-of-hospital cardiac arrests (OHCAs). METHODS Baseline data were prospectively collected by fire departments for their adult (16 years or older) OHCA and PRA patients from April 2003 through March 2010. We extracted those who had PRA prior to EMT arrival. The EMT- and bystander-witnessed OHCA patients who underwent CPR were also extracted as control groups. RESULTS There were 178 cases of PRA prior to EMT arrival. The majority (164/178) of these individuals were in a deep coma and met the criteria for the initiation of bystander CPR. Approximately 61% (108/178) of these PRAs were followed by cardiac arrests, which were classified as EMT-witnessed OHCAs by the Utstein template. The EMTs manually ventilated the patients until the cardiac arrest occurred. The 1-Y survival of this subgroup was the lowest of the PRA and PRA-related OHCA subgroups and was significantly lower than that of bystander-witnessed OHCAs with bystander CPR, when trauma and terminal illness cases were excluded (adjusted odds ratio=3.888 (1.103-24.827)). CONCLUSIONS We identified a subgroup of PRAs with unexpectedly poor outcomes. The BLS guidelines for healthcare providers including EMTs should be re-evaluated by a large prospective study.

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.