Outcomes from out-of-hospital cardiac arrest in Detroit

OBJECTIVE: To determine the out-of-hospital cardiac arrest survival rate, and prevalence of modifiable factors associated with survival, in Detroit, Michigan, over a 6-month period of time in 2002. METHODS: A retrospective review of all out-of-hospital cardiac arrests responded to by the Detroit Fire Department, Division of Emergency Medical Services. All elements of the EMS runsheet were transcribed to a database for analysis. Patient hospital records were reviewed to determine survival to hospital admission. All survivors to hospital admission were surveyed later in the Michigan Department of Vital Records death registry search. RESULTS: During this study timeframe, there were 538 confirmed out-of-hospital cardiac arrests within the City of Detroit, of which 67 were excluded for being dead on scene [51 (12.5%)] or having no available hospital records [16 (3.0%)]. Of the remaining 471 patients, 443 (94.1%) died before hospital admission. Only 44 (9.9%) of the 471 patients had a first recorded rhythm of ventricular fibrillation (VF), and 339 (76.5%) were asystolic. Of the 28 patients who survived to hospital admission, only 2 (7.1%) were noted to have a first rhythm of VF, and 15 (53.6%) were asystolic. Only one patient survived to hospital discharge. CONCLUSIONS: In this urban setting, out-of-hospital cardiac arrest is an almost uniformly fatal event.     

Outcomes following out-of-hospital cardiac arrest with an initial cardiac rhythm of asystole or pulseless electrical activity in Victoria,Australia

Background

While internationally reported survival from out-of-hospital cardiac arrest (OHCA) is improving, much of the increase is being observed in patients presenting to emergency medical services (EMS) in shockable rhythms. The purpose of this study was to assess survival and 12-month functional recovery in patients presenting to EMS in asystole or pulseless electrical activity (PEA).

Methods

The Victorian Ambulance Cardiac Arrest Registry was searched for adult OHCA patients presenting in non-shockable rhythms in Victoria, Australia between 1st July 2003 and 30th June 2013. We excluded patients defibrillated prior to EMS arrival and arrests witnessed by EMS. Twelve-month quality-of-life interviews were conducted on survivors who arrested between 1st January 2010 and 31st December 2012. The main outcome measures were survival to hospital discharge and 12-month functional recovery measured by the Extended Glasgow Outcome Scale (GOSE).

Results

A total of 38,378 non-shockable OHCA attended by EMS were included, of which 88.0% were asystole and 11.6% were PEA. Of the patients receiving resuscitation, survival to hospital discharge was 1.1% for asystole and 5.9% for PEA (p < 0.001), with no significant improvement observed over the 10 year study period. In survivors with 12-month follow-up data, the combined rate of death, vegetative state or lower severe disability was 66.7% (95% CI 41.0–80.0%) for asystole and 44.7% (95% CI 30.2–59.9%) for PEA.

Conclusion

Survival outcomes following OHCA with initial rhythms of asystole or PEA did not improve over the 10-year study period. Our findings indicate high rates of death within 12 months, and unfavourable functional recovery for survivors.     

Direction of first bystander call for help is associated with outcome from out-of-hospital cardiac arrest

Background

Preventable bystander delays following out-of-hospital cardiac arrest (OHCA) are common, and include bystanders inappropriately directing their calls for help.

Methods

We retrospectively extracted Utstein-style data from the Victorian Ambulance Cardiac Arrest Registry (VACAR) for adult OHCA occurring in Victoria, Australia, between July 2002 and June 2012. Emergency medical service (EMS) witnessed events were excluded. Cases were assigned into two groups on the basis of the first bystander call for help being directed to EMS. Study outcomes were: likelihood of receiving EMS treatment; survival to hospital, and; survival to hospital discharge.

Results

A total of 44 499 adult OHCA cases attended by EMS were identified, of which first bystander calls for help were not directed to EMS in 2842 (6.4%) cases. Calls to a relative, friend or neighbour accounted for almost 60% of the total emergency call delays. Patient characteristics and survival outcomes were consistently less favourable when calls were directed to others. First bystander call to others was independently associated with older age, male gender, arrest in private location, and arrest in a rural region. The risk-adjusted odds of treatment by EMS (OR 1.33, 95% CI 1.20–1.48), survival to hospital (OR 1.64, 95% CI 1.37–1.96) and survival to hospital discharge (OR 1.64, 95% CI 1.13–2.36) were significantly improved if bystanders called EMS first.

Conclusion

The frequency of inappropriate bystander calls following OHCA was low, but associated with a reduced likelihood of treatment by EMS and poorer survival outcomes.     

Evaluation of emergency medical dispatch in out-of-hospital cardiac arrest in Taipei

INTRODUCTION: Emergency medical dispatchers are the entry points to the emergency medical services (EMS). The overall performances of the dispatchers are imperative determinants of the emergency medical services dispatching system. There is little data on the cultural and language impacts on emergency medical dispatch. OBJECTIVE: This study examined the emotional content and cooperation score (ECCS) among Mandarin Chinese speaking callers for cardiac arrests, and evaluated the performances of emergency medical services dispatching system in Taipei. METHODS: This retrospective, observational study examined dispatching audio recordings obtained from the Taipei City Fire Department Dispatching Center between January 2004 to April 2004. The tapes of call relating to adult (age >or=18 years), non-traumatic cases with a presumed or field diagnosis of out-of-hospital cardiac arrest (OHCA) underwent systemic review. The caller's ECCS and the dispatcher's performances, including interview skills, provision of telephone-assisted cardiopulmonary resuscitation (T-CPR), and dispatcher's ability to identify OHCA were examined. Interrater reliability for determining ECCS and interview skills were assessed using kappa statistic. RESULTS: A total of 199 audio recordings were reviewed. A mean ECCS of 1.42+/-0.64 (95% CI: 1.33-1.51) demonstrated that most callers were emotionally stable and cooperative when calling for help, even when facing cardiac arrest patients. There was a good association between ECCS and the sex of the callers (male 1.32 versus female 1.49; p<0.05). In 82% of interviews, the interview skills of the dispatchers was high (4 or 5 points); while in one fifth the interview skills were suboptimal. About one third of the cases were provided with T-CPR by the dispatchers. The sensitivity and positive predictive value (PPV) for predicting OHCA by dispatchers were 96.9% and 97.9%, respectively. A kappa value of 0.65 and 0.68 were obtained for the interrater reliability of ECCS and interview skills. CONCLUSION: Most callers were found to be emotional stable and cooperative with dispatcher's interrogations when calling for cardiac arrest victims in this Mandarin speaking population. The dispatchers have shown satisfactory interview skills in approaching emergency calls and a good ability to identify OHCA. There is a low rate of T-CPR offered to the callers in the investigation. Efforts should be made to address the deficiencies in order to maximise the function of the EMS.     

New treatment bundles improve survival in out-of-hospital cardiac arrest patients: A historical comparison

Introduction

Before the introduction of the new international cardiac arrest treatment guidelines in 2005, patients with out-of-hospital cardiac arrest (OHCA) of cardiac origin in Northern Italy had very poor prognosis. Since 2006, a new bundle of care comprising use of automated external defibrillators (AEDs) and therapeutic hypothermia (TH) was started, while extracorporeal CPR program (ECPR) for selected refractory CA and dispatcher-assisted cardio-pulmonary resuscitation (CPR) was started in January 2010.

Objectives

We hypothesized that a program of bundled care might improve outcome of OHCA patients.

Methods

We analyzed data collected in the OHCA registry of the MB area between September 2007 and August 2011 and compared this with data from 2000 to 2003.

Results

Between 2007 and 2011, 1128 OHCAs occurred in the MB area, 745 received CPR and 461 of these had a CA of presumed cardiac origin. Of these, 125 (27%) achieved sustained ROSC, 60 (13%) survived to 1 month, of whom 51 (11%) were discharged from hospital with a good neurological outcome (CPC ≤ 2), and 9 with a poor neurological outcome (CPC > 2).Compared with data from the 2000 to 2003 periods, survival increased from 5.6% to 13.01% (p < 0.0001). In the 2007–2011 group, low-flow time and bystander CPR were independent markers of survival.

Conclusions

OHCA survival has improved in our region. An increased bystander CPR rate associated with dispatcher-assisted CPR was the most significant cause of increased survival, but duration of CA remains critical for patient outcome.     

Association of the time to first epinephrine administration and outcomes in out-of-hospital cardiac arrest: SOS-KANTO 2012 study

Objective

This study assessed the association between the timing of first epinephrine administration (EA) and the neurological outcomes following out-of-hospital cardiac arrests (OHCAs) with both initial shockable and non-shockable rhythms.

A composite model of survival from out-of-hospital cardiac arrest using the Cardiac Arrest Registry to Enhance Survival (CARES)

ObjectiveUsing CARES data, to develop a composite multivariate logistic regression model of survival for projecting survival rates for out-of-hospital arrests of presumed cardiac etiology (OHCA).MethodsThis is an analysis of 25,975 OHCA cases (from October 1, 2005 to December 31, 2011) occurring before EMS/first responder arrival and involving attempted resuscitation by responders from 125 EMS agencies.ResultsThe survival-at-hospital discharge rate was 9% for all cases, 16% for bystander-witnessed cases, 4% for unwitnessed cases, and 32% for bystander-witnessed pVT/VF cases. The model was estimated separately for each set of cases above. Generally, our first equation showed that joint presence of a presenting rhythm of pVT/VF and return of spontaneous circulation in the pre-hospital setting (PREHOSPROSC) is a substantial direct predictor of patient survival (e.g., 55% of such cases survived). Bystander AED use, and, for witnessed cases, bystander CPR and response time are significant but less sizable direct predictors of survival. Our second equation shows that these variables make an additional, indirect contribution to survival by affecting the probability of joint presence of pVT/VF and PREHOSPROSC. The model yields survival rate projections for various improvement scenarios; for example, if all cases had involved bystander AED use (vs. 4% currently), the survival rate would have increased to 14%. Approximately one-half of projected increases come from indirect effects that would have been missed by the conventional single-equation approach.ConclusionThe composite model describes major connections among predictors of survival, and yields specific projections for consideration when allocating scarce resources to impact OHCA survival.     

A national resuscitation registry of out-of-hospital cardiac arrest in Germany—A pilot study

Background

Survival rate after out-of-hospital cardiac arrest (OHCA) has not significantly increased over the last decade. However, survival rate has been used as a quality benchmark for many emergency medical services. A uniform resuscitation registry may be advantageous for quality management of cardiopulmonary resuscitation (CPR). This study was conducted to evaluate the establishment of a national CPR registry in Germany.

Materials and methods

A prospective cohort study was performed that included 469 patients who experienced OHCA requiring CPR in the metropolitan area of Dortmund, Germany. Cardiac arrest was defined as concomitant appearance of unconsciousness, apnoea or gasping and pulselessness. All data were collected via a secure and confidential paper-based method as the data set ‘Preclinical care’.

Results

Quality of data was classified as ‘good’ in 33.4%, ‘moderate’ in 48.4%, and ‘bad’ in 18.2% of the patients, respectively. Sixty-two percent had OHCA in private residences, 24% of the patients had a first monitored rhythm of ventricular fibrillation (VF) or ventricular tachycardia (VT), 35.2% had return of spontaneous circulation (ROSC) on scene, and patients presenting VF/VT as the first monitored rhythm had higher ROSC rates (51.3%) compared to patients with asystole (22.6%).

Conclusion

The data set ‘Preclinical care’ proved to be congruent with the Utstein style, provided further information for national and international comparisons, and enabled a detailed analysis. Optimisation of data collection and introduction of strict control mechanisms may further improve data quality.     

The use of prehospital variables to predict acute coronary artery disease in failed resuscitation attempts for out-of-hospital cardiac arrest

Aim of the studyTo determine the ability of readily available prehospital variables to predict acute coronary artery disease (CAD) as the cause of arrest in failed out-of hospital cardiac arrest (OHCA) resuscitations.MethodsRetrospective analysis of a prospectively collected database of all adult cases of OHCA who underwent resuscitation attempts and later post-mortem examination by the state Medical Examiner (ME) over a 6 year period. Multivariable logistic regression modeling was used to identify predictors.ResultsAmong the 151 cases linked to ME reports, CAD was judged to be the cause of arrest in 65/151 (43%). In multivariable modeling, CAD was more likely to be found at autopsy among older victims (Odds ratio [OR] 2.3 per decade of life, 95% confidence interval [CI] 1.6–3.4), males (OR 7.3, 95% CI 1.9–27.4), and those with an initial shockable rhythm (OR 5.3, 95% CI 2.0–14.2). The combination of these three variables correctly classified 75% of victims with an area under the ROC curve (AUC) of 0.85.ConclusionAs hospital-based salvage therapies offer opportunities to extend survival for victims of OHCA who fail prehospital treatment, an ability to predict CAD may help guide protocols for appropriate use. In this derivation analysis, a simple set of variables available on scene can be used to predict CAD with good accuracy among OHCA victims who fail prehospital resuscitation attempts. An initial shockable rhythm should still be considered the result of acute coronary artery disease until proven otherwise.     

Exploring gender differences and the “oestrogen effect” in an Australian out-of-hospital cardiac arrest population

Background

Recent studies have suggested gender differences in out-of-hospital cardiac arrests (OHCA) including outcomes favouring young women. We aimed to investigate these findings in an Australian OHCA population using the Victorian Ambulance Cardiac Arrest Registry (VACAR).

Methods and results

The VACAR was searched for adult presumed cardiac OHCAs between 2003 and 2010 where Emergency Medical Services (EMS) attempted resuscitation. Gender and age differences in survival to hospital arrival and to hospital discharge were examined using logistic regression adjusting for known predictors of survival. There were 10,453 OHCA meeting inclusion criteria (863 aged between 18 and 44 years). Women were less likely to be younger, have a witnessed arrest, receive bystander CPR, arrest in a public place, have an initial shockable rhythm or receive transport to 24-h cardiac interventional hospital. After adjusting for differences in pre-hospital factors, women were more likely to survive to hospital arrival than men (aOR 3.47, 95% CI: 2.19–5.50), but no gender differences were seen in survival to hospital discharge either overall or specifically in women aged between 18 and 44 years. Both younger men and younger women were more likely to survive to hospital discharge compared to older men and women.

Conclusion

Women were more likely to survive to hospital arrival despite less favourable baseline variables. However, this initial improvement in survival did not translate to better survival to hospital discharge either overall, or in women of a reproductive age. Further study is required to determine gender differences in the underlying causes of OHCA and in EMS transportation practices.     

Survival rates in out-of-hospital cardiac arrest patients transported without prehospital return of spontaneous circulation: An observational cohort study

Background

Some Emergency Medical Services currently use just one component of the Universal Termination of Resuscitation (TOR) Guideline, the absence of prehospital return of spontaneous circulation (ROSC), as the single criteria to terminate resuscitation, which may deny transport to potential survivors.

Objective

This study aimed to report the survival to hospital discharge rate in non-traumatic, adult out-of-hospital cardiac arrest (OHCA) patients transported to hospital without a prehospital ROSC.

Methods

An observational study of OHCA patients without a prehospital ROSC who met the Universal TOR Guideline for transport to hospital with ongoing resuscitation. Multivariable logistic regression was used to determine the association of each variable with survival to hospital discharge.

Results

Of 20,207 OHCA treated by EMS, 3374 (16.4%) did not have a prehospital ROSC but met the Universal TOR guideline for transport to hospital with ongoing resuscitation. Of these patients, 122 (3.6%) survived to hospital discharge. Survival to discharge was associated with initial shockable VF/VT rhythms (OR 5.07; 95% CI 2.77–9.30), EMS-witnessed arrests (OR 3.51; 95% CI 1.73–7.15), bystander-witnessed arrests (OR 2.11; 95% CI 1.18–3.77), and public locations (OR 1.57; 95% CI 1.02–2.40).

Conclusion

In OHCA patients without a prehospital ROSC who met the Universal TOR Guideline for transport with ongoing resuscitation survival rates were above the 1% futility rate. Employing only the lack of ROSC as criteria for termination of resuscitation may miss survivors after OHCA.     

The incidence and significance of emesis associated with out-of-hospital cardiac arrest

STUDY OBJECTIVE: Studies have suggested that emesis may occur in up to a third of cardiac arrest patients. The goal of this investigation was to characterize the frequency, timing, and outcome association of emesis in persons suffering out-of-hospital cardiac arrest in order to understand the role and care-implications of emesis better. METHODS: We conducted a cohort study of persons 18 years and over suffering non-traumatic out-of-hospital cardiac arrests who received attempted resuscitation by paramedics in the study community from January 1, 2004 through December 31, 2005 (n=1009). The presence and timing of emesis were determined by paramedics and recorded on the Emergency Medical Services report form. We used logistic regression analyses to assess whether emesis was independently associated with survival to hospital discharge. RESULTS: The presence or absence of emesis was documented in 76% (1009/1333) of cases. Emesis was present in 32% (318/1009). Two-thirds (208/312) of emesis occurred prior to EMS arrival; 28% (88/312) of episodes occurred between EMT arrival and intubation; and 4% (13/312) occurred after intubation. After adjustment for potential confounders, the presence of emesis was associated with a decreased odds of survival to hospital discharge among all-rhythm arrest (Odds ratio (OR)=0.50 [0.28-0.89]) and ventricular fibrillation arrest (OR=0.52 [0.27-0.98]). CONCLUSION: Given the frequency of emesis, the potential that some portion of emesis may be related to care, and the adverse association between emesis and survival, approaches that treat or prevent emesis better may improve the chances of survival following out-of-hospital cardiac arrest.     

Derivation and initial application of a standard population for out-of-hospital cardiac arrest (SPOHCA)

AimWhile adjusting data for age, sex, race and/or socio-economic status is well established in out-of-hospital cardiac arrest (OHCA) research, there are shortcomings to reporting and comparing population-based OHCA outcomes. The purpose of this study was to derive a case-based standard population specific to EMS treated adult OHCA (SPOHCA) in the U.S., and demonstrate its application.MethodsThe proposed SPOHCA was developed from three sources of multi-site OHCA data: the Cardiac Arrest Registry to Enhance Survival (CARES); the National EMS Information System (NEMSIS); and a published report from the Resuscitation Outcomes Consortium (ROC). OHCA data from a single EMS system were then used to demonstrate the application of SPOHCA. We report raw survival, population-based survival adjusted to the U.S. population, and the new SPOHCA-adjusted survival.ResultsObserved raw survival was 12.3%. Adjustment to the demographic make-up of the adult U.S. population produced an adjusted incidence of 94.2 OHCA per 100,000 p-y, with a survival rate of 9.8 per 100,000 p-y. Using the proposed SPOHCA to adjust survival data produced an adjusted survival rate of 12.4%.ConclusionA case-based standard population provides for more practical interpretation of reported OHCA outcomes. We encourage a more widespread effort involving multiple stakeholders to further explore the effects of adjusting OHCA outcomes using the proposed SPOHCA instead of population-based demographics.     

Survival from out-of-hospital cardiac arrest in New Zealand following the 2005 resuscitation guideline changes

Aims

The effect of cardiopulmonary resuscitation guideline changes on out-of-hospital survival rates and defibrillation efficacy was investigated. The guideline changes were those recommended by the International Liaison Committee on Resuscitation in 2005.

Methods

A retrospective comparative study was undertaken of out-of-hospital cardiac arrests in the Wellington region. The effect of guideline changes between the periods of 1st July 2005-30th June 2006 and 1st June 2007-31st May 2008 was examined. Data was collected from Wellington Free Ambulance and hospital records in accordance with the Utstein template. The primary outcome measure was survival to hospital discharge. Additional end points included individual shock success, return of spontaneous circulation (ROSC) and survival to hospital admission.

Results

There was no significant increase in survival to hospital discharge with 11% (18/162) pre-change and 12% (20/170) post-change (p = 0.5). First-shock efficacy decreased from 68% (65/96) to 62% (57/92) (p = 0.75). Second shock efficacy decreased from 47% (14/30) to 27% (9/33) (p = 0.12). The proportion of patients with ROSC increased from 34% (55/162) to 42% (72/170) (p = 0.07, Chi squared). The proportion surviving to hospital increased significantly from 22% (36/162) to 36% (61/170) (p = 0.006). Withdrawal of atropine in 2005 had no adverse effect on the outcome.

Conclusion

This study suggests that in the Wellington Region of New Zealand, the new guidelines have improved survival to hospital but not to discharge. Whilst the guideline changes have resulted in a trend towards decreased shock success rates, ROSC and survival to hospital admission have both increased.     

The time dependent association of adrenaline administration and survival from out-of-hospital cardiac arrest

BackgroundRecommended for decades, the therapeutic value of adrenaline (epinephrine) in the resuscitation of patients with out-of-hospital cardiac arrest (OHCA) is controversial.PurposeTo investigate the possible time-dependent outcomes associated with adrenaline administration by Emergency Medical Services personnel (EMS).MethodsA retrospective analysis of prospectively collected data from a near statewide cardiac resuscitation database between 1 January 2005 and 30 November 2013. Multivariable logistic regression was used to analyze the effect of the time interval between EMS dispatch and the initial dose of adrenaline on survival. The primary endpoints were survival to hospital discharge and favourable neurologic outcome.ResultsData from 3469 patients with witnessed OHCA were analyzed. Their mean age was 66.3 years and 69% were male. An initially shockable rhythm was present in 41.8% of patients. Based on a multivariable logistic regression model with initial adrenaline administration time interval (AATI) from EMS dispatch as the covariate, survival was greatest when adrenaline was administered very early but decreased rapidly with increasing (AATI); odds ratio 0.94 (95% Confidence Interval (CI) 0.92–0.97). The AATI had no significant effect on good neurological outcome (OR = 0.96, 95% CI = 0.90–1.02).ConclusionsIn patients with OHCA, survival to hospital discharge was greater in those treated early with adrenaline by EMS especially in the subset of patients with a shockable rhythm. However survival rapidly decreased with increasing adrenaline administration time intervals (AATI).     

Service factors and health status of survivors of out-of-hospital cardiac arrest

To determine how emergency service factors affect the health status of survivors of out-of-hospital cardiac arrest, 424 survivors were studied six months later. The principal research tool was the Sickness Impact Profile (SIP), a behaviorally-based instrument for measuring sickness-related dysfunction. Time to initiation of care and time to definitive care were significantly related to dysfunction. The critical time intervals can be influenced by the manner in which communities provide emergency care.     

Regional variability in survival outcomes of out-of-hospital cardiac arrest: The All-Japan Utstein Registry

Objective

There is a paucity of studies on the degree of regional variability in out-of-hospital cardiac arrest (OHCA) outcomes, particularly in neurological outcome. This study aimed to determine whether there is a significant regional variation in survival outcomes of OHCA across Japan.

Methods

We analyzed a prospective, nation-wide, population-based database (All-Japan Utstein Registry) involving all Japanese individuals who had non-traumatic OHCA resuscitated by emergency responders from January 2005 through December 2010. The primary study endpoint was favourable neurological survival at 1 month, defined as Cerebral Performance Category 1 or 2. We compared unadjusted and multivariable-adjusted rates of the outcome among seven geographic regions.

Results

In the total catchment population of 128 million, there were 539,641 non-traumatic OHCA patients. Unadjusted neurologically favourable survival varied across regions from 1.9% to 3.1% (rate difference, 1.2%; 95%CI, 1.0–1.3%); the Northeast region had a significantly lower rate compared to the Midwest region (unadjusted rate ratio, 0.62; 95%CI, 0.60–0.64). This disparity became larger after adjusting for patient- and prehospital-level confounders (adjusted rate ratio, 0.52; 95%CI, 0.51–0.54). Among 35,153 OHCA patients with return of spontaneous circulation, unadjusted neurologically favourable survival varied from 26.4% to 34.7% (rate difference, 8.3%; 95%CI, 6.6–10.1%); the East region had a significantly lower rate compared to the Midwest region (adjusted rate ratio, 0.72; 95%CI, 0.68–0.76).

Conclusion

In this prospective, nation-wide, population-based study in Japan, we found a two-fold regional difference in neurologically favourable survival after OHCA, suggesting regional disparities in prehospital care and in-hospital post-resuscitation care.     

Impact of the number of on-scene emergency life-saving technicians and outcomes from out-of-hospital cardiac arrest in Osaka City

Backgrounds

In Japan, ambulance staffing for cardiac arrest responses consists of a 3-person unit with at least one emergency life-saving technician (ELST). Recently, the number of ELSTs on ambulances has increased since it is believed that this improves the quality of on-scene care leading to better outcomes from out-of-hospital cardiac arrest (OHCA). The objective of this study was to evaluate the association between the number of on-scene ELSTs and OHCA outcome.

Methods

This was a prospective cohort study of all bystander-witnessed OHCA patients aged ≥18 years in Osaka City from January 2005 to December 2007 using on an Utstein-style database. The primary outcome measure was one-month survival with favorable neurological outcome defined as a cerebral performance category ≤2. Multivariable logistic regression model were used to assess the contribution of the number of on-scene ELSTs to the outcome after adjusting for confounders.

Results

Of the 2408 bystander-witnessed OHCA patients, one ELST group was present in 639 (26.5%), two ELST were present in 1357 (56.4%), and three ELST group in 412 (17.1%). The three ELST group had a significantly higher rate of one-month survival with favorable neurological outcome compared with the one ELST group (8.0% versus 4.5%, adjusted OR 2.26, 95% CI 1.27–4.04), while the two ELST group did not (5.4% versus 4.5%, adjusted OR 1.34, 95% CI 0.82–2.19).

Conclusions

Compared with the one on-scene ELST group, the three on-scene ELST group was associated with the improved one-month survival with favorable neurological outcome from OHCA in Osaka City.     

Scene time interval and good neurological recovery in out-of-hospital cardiac arrest

Objectives

It is unclear whether scene time interval (STI) is associated with better neurological recovery in the emergency medical service (EMS) system with intermediate service level.

The relationship between survival after out-of-hospital cardiac arrest and process measures for emergency medical service ambulance team performance

ObjectiveInternational institutes have developed their own clinical performance indicators for ambulance services. It is unknown whether these process measures are related to survival of patients after out-of-hospital cardiac arrest (OHCA). We aimed to determine whether Emergency Medical Service (EMS)-related ambulance team process measures correlate with patient survival.MethodsFour years of observational data were collected from an urban EMS OHCA registry. The two process measures were achieving an EMS response time ≤4 min and prehospital ROSC (return of spontaneous circulation). The outcome measure was survival to discharge. We used the GLMM (generalised linear mixed model) with stepwise selection to examine this process-outcome link at the patient and EMS team levels, respectively.ResultsWe analyzed 3856 OHCA patients distributed across forty-three EMS ambulance teams. Survival to discharge was observed in 193 (5%) patients. The two EMS team process measures were positively associated with an improvement in survival at the patient level after case-mix adjustment. However, they were not associated with improvement in the risk-adjusted survival rate.ConclusionsThe EMS team-level process measures proposed by international institutes may not predict the risk-adjusted survival rate. Using these measures to motivate EMS teams to improve their quality performance would be questionable. Increased efforts should be devoted to constructing more pivotal EMS team-level process measures that are tightly linked to survival.