Traumatic out-of-hospital cardiac arrests in Melbourne, Australia

Introduction

Many consider attempted resuscitation for traumatic out-of-hospital cardiac arrest (OHCA) futile. This study aims to describe the characteristics and profile of adult traumatic OHCA.

Methods

The Victorian Ambulance Cardiac Arrest Registry (VACAR) was used to identify all trauma related cases of OHCA in patients aged ≥16 years.

Results

Between 2000 and 2009, EMS attended 33,178 OHCAs of which 2187 (6.6%) had a traumatic aetiology. The median age (IQR) of traumatic OHCA cases was 36 (25–55) years and 1612 were male (77.5%). Bystander CPR was performed in 201 cases (10.2%) with median (IQR) EMS response time 8 (6–11) min. The first recorded rhythm by EMS was asystole seen in 1650 (75.4%), PEA in 294 (13.4%) cases and VF in 35 cases (1.6%). Cardiac output was present in 208 (9.5%) cases who subsequently had an EMS witnessed OHCA. EMS attempted resuscitation in 545 (24.9%) patients of whom 84 (15.4%) achieved ROSC and were transported, and 27 (5.1%) survived to hospital discharge; 107 were transported with CPR of whom 8 (7.4%) survived to hospital discharge. Where EMS attempted resuscitation in traumatic OHCAs, survival for VF was 11.8% (n = 4), PEA 5.1% (n = 10) and asystole 2.4% (n = 3). In EMS witnessed traumatic OHCA, resuscitation was attempted in 175 cases (84.1%), 35 (16.8%) patients achieved sustained ROSC before transport of whom 5 (14%) survived to leave hospital and 60 (28.8%) were transported with CPR of whom 6 (10%) survived to leave hospital. Compared to OHCA cases with ‘presumed cardiac’ aetiology traumatic OHCAs were younger [median years (IQR): 36 (25–55) vs 74 (61–82)], had resuscitation attempted less (25% vs 48%), were less likely to have a shockable rhythm (1.6% vs 17.1%), were more likely to be witnessed (62.8% vs 38.1%) and were less likely to receive bystander CPR (10.2% vs 25.5%) (p < 0.001, respectively). Multivariate logistic regression identified factors associated with EMS decision to attempt resuscitation. The odds ratio [OR (95% CI)] for ‘presence of bystander CPR’ was 5.94 (4.11–8.58) and for ‘witnessed arrest’ was 2.60 (1.86–3.63).

Conclusion

In this paramedic delivered EMS attempted resuscitation was not always futile in traumatic OHCA with a survival of 5.1%. The quality of survival needs further study.     

Outcome of out-of-hospital cardiac arrests in Beijing,China

Aim

The purpose of this study was to assess the outcome of out-of-hospital cardiac arrests (OHCAs) in Beijing, China.

Methods

In this prospective study, data were collected according to the Utstein style on all cases of OHCA that occurred between January and December 2012 in urban areas covered by Beijing Emergency Medical Services (EMS). The cases were followed-up for 1 year.

Results

Out of the 9897 OHCAs recorded, cardiopulmonary resuscitation (CPR) was initiated in 2421 patients (24.4%). Among the CPR-receivers (n = 2421), 1804 patients (74.5%) had collapsed at home, while 375 patients (15.5%) at a public place. The average time interval from call to EMS arrival at the collapse location was 16 min (range, 4–43 min). Of the 1693 OHCA cases with cardiac aetiology, 1246 cases (73.6%) were witnessed, and basic CPR was performed by bystanders before arrival of the EMS personnel in 193 patients (11.4%). Of the OHCAs with cardiac aetiology, 1054 patients (62.3%) had asystole, 131 patients (7.7%) had shockable rhythms, restoration of spontaneous circulation was achieved in 85 patients (5.0%), 71 patients (4.2%) were admitted to the hospital alive, and of the 22 patients (1.3%) who were discharged alive, 17 patients (1%) had good neurological outcomes. At 1 year post-OHCA, 17 patients were alive.

Conclusion

In the urban areas of Beijing with EMS services, survival rate after OHCA was unsatisfactory. Improvements are required in every link of the ‘chain of survival’.     

A randomized trial of compression first or analyze first strategies in patients with out-of-hospital cardiac arrest: results from an Asian community

Background

It is still under debate whether a period of cardiopulmonary resuscitation should be performed prior to rhythm analysis for defibrillation for out of hospital cardiac arrests (OHCA). This study compared outcomes of OHCA treated by “compression first” (CF) versus “analyze first” (AF) strategies in an Asian community with low rates of shockable rhythms.

Methods

This randomized trial was conducted in Taipei City between February 2008 and December 2009. Dispatches of suspected OHCA that activated advanced life support teams were randomized into the CF and AF strategies. Patients assigned to CF strategy received 10 cycles of CPR prior to analysis by automatic external defibrillator. The primary outcome was sustained (>2 h) return of spontaneous circulation (ROSC) and secondary outcome was survival to hospital discharge.

Results

We included 289 cases in the final analysis after exclusion by pre-specified criteria, 141 were allocated to CF strategy and 148 to AF strategy. Baseline characteristics were similar. Thirty-seven (26.2%) of those receiving CF strategy and 49 (33.1%) of the AF strategy achieved sustained ROSC (p = 0.25). In a post-hoc analysis of patients who achieved ROSC, those that received CF strategy were more likely to be discharged alive from the hospital (16/37 = 43.2% vs. 11/49 = 22.4%, p = 0.02).

Conclusion

In this study population of low rates of shockable rhythms, there was no difference in ROSC for CF or AF strategies. Considering the EMS operation situations, a period of paramedic-administered CPR for up to 10 cycles prior to rhythm analysis could be a feasible strategy in this community.     

The continuous quality improvement project for telephone-assisted instruction of cardiopulmonary resuscitation increased the incidence of bystander CPR and improved the outcomes of out-of-hospital cardiac arrests

Review

In 2007, the Ishikawa Medical Control Council initiated the continuous quality improvement (CQI) project for telephone-assisted cardiopulmonary resuscitation (telephone-CPR), which included instruction on chest-compression-only CPR, education on how to recognise out-of-hospital cardiac arrests (OHCAs) with agonal breathing, emesis and convulsion, recommendations for on-line or redialling instructions and feedback from emergency physicians. This study aimed to investigate the effect of this project on the incidence of bystander CPR and the outcomes of OHCAs.

Materials and methods

The baseline data were prospectively collected on 4995 resuscitation-attempted OHCAs, which were recognised or witnessed by citizens rather than emergency medical technicians during the period of February 2004 to March 2010. The incidence of telephone-CPR and bystander CPR, as well as the outcomes of the OHCAs, was compared before and after the project.

Results

The incidence of telephone-CPR and bystander CPR significantly increased after the project (from 42% to 62% and from 41% to 56%, respectively). The incidence of failed telephone-CPR due to human factors significantly decreased from 30% to 16%. The outcomes of OHCAs significantly improved after the projects. A multiple logistic regression analysis revealed that the CQI project is one of the independent factors associated with one-year (1-Y) survival with favourable neurological outcomes (odds ratio = 1.81, 95% confidence interval = 1.20–2.76).

Conclusions

The CQI project for telephone-CPR increased the incidence of bystander CPR and improved the outcome of OHCAs. A CQI project appeared to be essential to augment the effects of telephone-CPR.     

Bystander-initiated CPR in an Asian metropolitan: Does the socioeconomic status matter?

Objectives

To determine the association of neighborhood socioeconomic status (SES) with bystander-initiated cardiopulmonary resuscitation (CPR) and patient outcomes of out of hospital cardiac arrests (OHCAs) in an Asian metropolitan area.

Methods

We performed a retrospective study in a prospectively collected cohort from the Utstein registry of adult non-traumatic OHCAs in Taipei, Taiwan. Average real estate value was assessed as the first proxy of SES. Twelve administrative districts in Taipei City were categorized into low versus high SES areas to test the association. The primary outcome was bystander-initiated CPR, and the secondary outcome was patient survival status. Factors associated with bystander-initiated CPR were adjusted for in multivariate analysis. The mean household income was assessed as the second proxy of SES to validate the association.

Results

From January 1, 2008 to December 30, 2009, 3573 OHCAs received prehospital resuscitation in the community. Among these, 617 (17.3%) cases received bystander CPR. The proportion of bystander CPR in low-SES vs. high-SES areas was 14.5% vs. 19.6% (p < 0.01). Odds ratio of receiving bystander-initiated CPR in low-SES areas was 0.72 (95% confidence interval: [0.60–0.88]) after adjusting for age, gender, witnessed status, public collapse, and OHCA unrecognized by the online dispatcher. Survival to discharge rate was significantly lower in low-SES areas vs. high-SES areas (4.3% vs. 6.8%; p < 0.01). All results above remained consistent in the analyses by mean household income.

Conclusions

Patients who experienced an OHCA in low-SES areas were less likely to receive bystander-initiated CPR, and demonstrated worse survival outcomes.     

Use of automated external defibrillators in patients with traumatic out-of-hospital cardiac arrest

Background

Because out-of-hospital cardiac arrests (OHCAs) due to a major trauma rarely present with shockable rhythms, the potential benefits of using automated external defibrillators (AEDs) at the scene of traumatic OHCAs have not been examined.

Methods

We conducted an observational, retrospective cohort study using an Utstein-style analysis in Tainan city, Taiwan. The enrollees were adult patients with traumatic OHCAs accessed by emergency medical technicians (EMTs) from January 1, 2004 to December 31, 2010. The exposure was the use or non-use of AEDs at the scene, as determined by the clinical judgment of the EMTs. The primary outcome evaluated was a sustained (≥2 h) return of spontaneous circulation (ROSC), and the secondary outcomes were prehospital ROSC, overall ROSC, survival to hospital admission, survival at one month and favorable neurologic status at one month.

Results

A total of 424 patients (313 males) were enrolled, of whom 280 had AEDs applied, and 144 did not. Only 25 (5.9%) patients had received bystander cardiopulmonary resuscitation (CPR), and merely 21 (7.5%) patients in the AED group presented with shockable rhythms. Compared to the non-AED group, the primary and secondary outcomes of the AED group were not significantly different, except for a significantly lower prehospital ROSC rate (1.1% vs 4.9%, p < 0.05). Multivariate analysis showed no significant interactions between the use of AEDs and other key variables. Use of the AED was not associated with sustained ROSC (OR 1.33; 95% CI 0.75–2.38, p = 0.33).

Conclusions

In a community with a low prevalence of shockable rhythms and administration of bystander CPR in patients with traumatic OHCA, we found no significant differences in the sustained ROSC between the AED and the non-AED groups. Considering scene safety and the possible interruption of CPR, we do not encourage the routine use of AEDs at the scene of traumatic OHCAs.     

A trend in epidemiology and outcomes of out-of-hospital cardiac arrest by urbanization level: A nationwide observational study from 2006 to 2010 in South Korea

Background

The goal of this study is to better understand the trend in epidemiological features and the outcomes of emergency medical service (EMS)-assessed out-of-hospital cardiac arrest (OHCA) according to the community urbanization level: metropolitan, urban, and rural.

Methods

This study was performed within a nationwide EMS system with a single-tiered basic-to-intermediate service level and approximately 900 destination hospitals for eligible OHCA cases in South Korea (with 48 million people). A nationwide OHCA database, which included information regarding demographics, Utstein criteria, EMS, and hospital factors and outcomes, was constructed using the EMS run sheets of eligible cases who were transported by 119 EMS ambulances and followed by a medical record review from 2006 to 2010. Cases with an unknown outcome were excluded. The community urbanization level was categorized according to population size, with metropolitan areas (more than 500,000 residents), urban areas (100,000–500,000 residents), and rural areas (<100,000 residents). The primary end point was the survival to discharge rate. Age- and sex-adjusted survival rates (ASRs) and standardized survival ratios (SSRs) with 95% confidence intervals (CIs) were calculated compared to a standard population. The adjusted odds ratios (AORs) and 95% CIs for survival were calculated and adjusted for potential risk factors using stratified multivariable logistic regression analysis.

Results

There were 97,291 EMS-assessed OHCAs with 73,826 (75.9%) EMS-treated cases analyzed, after excluding the patients with unknown outcome (N = 4172). The standardized incidence rate increased from 37.5 in 2006 to 46.8 in 2010 per 100,000 person-years for EMS-assessed OHCAs, and the survival rate was 3.0% for EMS-assessed OHCAs (3.3% for cardiac etiology and 2.3% for non-cardiac etiology) and 3.6% for EMS-treated OHCAs. Significantly different trends were found by urbanization level for bystander CPR, EMS performance, and the level of the destination hospital. The ASRs for survival were significantly improved by year in the metropolitan areas (3.6% in 2006 to 5.3% in 2010) but remained low in the urban areas (1.4% in 2006 to 2.3% in 2010) and very low in the rural areas (0.5 in 2006 and 0.8 in 2010). The SSRs (95% CIs) in the metropolitan areas were 1.19 (1.06–1.34) in 2006 and 1.77 (1.64–1.92) in 2010, whereas the SSRs were observed to be less than 1.00 during the five-year period in both urban and rural areas. The AORs (95% CIs) for survival significantly increased to 1.42 (1.22–1.66) in the metropolitan areas and to 1.58 (1.18–2.11) in the urban areas while not increasing in the rural areas, compared to the level of each group of areas in 2006.

Conclusions

In this nationwide cohort study from 2006 to 2010, the standardized incidence rate and survival to discharge rate of EMS-assessed OHCAs increased annually in metropolitan and urban communities but did not increase in rural communities. Further investigations should be undertaken to improve the performance and outcomes in rural communities.     

Outcome after out-of-hospital cardiac arrest witnessed by EMS: Changes over time and factors of importance for outcome in Sweden

Background

Among patients who survive after out-of-hospital cardiac arrest (OHCA), a large proportion are recruited from cases witnessed by the Emergency Medical Service (EMS), since the conditions for success are most optimal in this subset.

Aim

To evaluate outcome after EMS-witnessed OHCA in a 20-year perspective in Sweden, with the emphasis on changes over time and factors of importance.

Methods

All patients included in the Swedish Cardiac Arrest Register from 1990 to 2009 were included.

Results

There were 48,349 patients and 13.5% of them were EMS witnessed. There was a successive increase in EMS-witnessed OHCA from 8.5% in 1992 to 16.9% in 2009 (p for trend < 0.0001). Among EMS-witnessed OHCA, the survival to one month increased from 13.9% in 1992 to 21.8% in 2009 (p for trend < 0.0001). Among EMS-witnessed OHCA, 51% were found in ventricular fibrillation, which was higher than in bystander-witnessed OHCA, despite a lower proportion with a presumed cardiac aetiology in the EMS-witnessed group.Among EMS-witnessed OHCA overall, 16.0% survived to one month, which was significantly higher than among bystander-witnessed OHCA.Independent predictors of a favourable outcome were: (1) initial rhythm ventricular fibrillation; (2) cardiac aetiology; (3) OHCA outside home and (4) decreasing age.

Conclusion

In Sweden, in a 20-year perspective, there was a successive increase in the proportion of EMS-witnessed OHCA. Among these patients, survival to one month increased over time. EMS-witnessed OHCA had a higher survival than bystander-witnessed OHCA. Independent predictors of an increased chance of survival were initial rhythm, aetiology, place and age.     

Factors complicating interpretation of capnography during advanced life support in cardiac arrest--a clinical retrospective study in 575 patients

Background

End tidal carbon dioxide (ETCO₂) monitoring during advanced life support (ALS) using capnography, is recommended in the latest international guidelines. However, several factors might complicate capnography interpretation during ALS. How the cause of cardiac arrest, initial rhythm, bystander cardiopulmonary resuscitation (CPR) and time impact on the ETCO₂ values are not completely clear. Thus, we wanted to explore this in out-of-hospital cardiac arrested (OHCA) patients.

Methods

The study was carried out by the Emergency Medical Service of Haukeland University Hospital, Bergen, Norway. All non-traumatic OHCAs treated by our service between January 2004 and December 2009 were included. Capnography was routinely used in the study, and these data were retrospectively reviewed together with Utstein data and other clinical information.

Results

Our service treated 918 OHCA patients, and capnography data were present in 575 patients. Capnography distinguished well between patients with or without return of spontaneous circulation (ROSC) for any initial rhythm and cause of the arrest (p < 0.001). Cardiac arrests with a respiratory cause had significantly higher levels of ETCO₂ compared to primary cardiac causes (p < 0.001). Bystander CPR affected ETCO₂-recordings, and the ETCO₂ levels declined with time.

Conclusions

Capnography is a useful tool to optimise and individualise ALS in cardiac arrested patients. Confounding factors including cause of cardiac arrest, initial rhythm, bystander CPR and time from cardiac arrest until quantitative capnography had an impact on the ETCO₂ values, thereby complicating and limiting prognostic interpretation of capnography during ALS.     

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.     

The impact of partial resuscitation attempts on the reported outcomes of out-of-hospital cardiac arrest in Victoria,Australia: Implications for Utstein-style outcome reports

Background

Success rates from cardiopulmonary resuscitation (CPR) are often quantified by Utstein-style outcome reports in populations who receive an attempted resuscitation. In some cases, evidence of futility is ascertained after a partial resuscitation attempt has been administered, and these cases reduce the overall effectiveness of CPR. We examine the impact of partial resuscitation attempts on the reported outcomes of out-of-hospital cardiac arrest (OHCA) in Victoria, Australia.

Methods

Between 2002 and 2012, 34,849 adult OHCA cases of presumed cardiac aetiology were included from the Victorian Ambulance Cardiac Arrest Registry. Resuscitation attempts lasting ≤10 min in cases which died on scene were defined as a partial resuscitation. We used logistic regression to identify factors associated with a partial resuscitation attempt in the emergency medical service (EMS) treated population. Survival outcomes with and without partial resuscitations were compared across included years.

Results

The proportion of partial resuscitations in the overall EMS treated population increased significantly from 8.6% in 2002 to 18.8% in 2012 (p for trend < 0.001), and were largely supported by documented evidence of irreversible death. Partial resuscitations were independently associated with older age, female gender, initial non-shockable rhythm, prolonged downtime, and lower skill level of EMS personnel. Selectively excluding partial resuscitations increased event survival by 7.6% (95% CI 4.1–11.2%), and survival to hospital discharge increased by 3.1% (95% CI 0.5–5.7%) in 2012 (p < 0.001 for both).

Conclusion

In our EMS system, evidence of futility was often identified after the commencement of a partial resuscitation attempt. Excluding these events from OHCA outcome reports may better reflect the overall effectiveness of CPR.     

Chest compression-only cardiopulmonary resuscitation performed by lay rescuers for adult out-of-hospital cardiac arrest due to non-cardiac aetiologies

Objective

Bystander CPR improves survival in patients with out-of-hospital cardiac arrest (OHCA). For adult sudden collapse, bystander chest compression-only CPR (COCPR) is recommended in some circumstances by the American Heart Association and European Resuscitation Council. However, adults who arrest from non-cardiac causes may also receive COCPR. Because rescue breathing may be more important for individuals suffering OHCA secondary to non-cardiac causes, COCPR is not recommended for these cases. We evaluated the relationship of lay rescuer COCPR and survival after OHCA from non-cardiac causes.

Methods

Analysis of a statewide Utstein-style registry of adult OHCA, during a large scale campaign endorsing COCPR for OHCA from presumed cardiac cause. The relationship between lay rescuer CPR (both conventional CPR and COCPR) and survival to hospital discharge was evaluated.

Results

Presumed non-cardiac aetiologies of OHCA accounted for 15% of all cases, and lay rescuer CPR was provided in 29% of these cases. Survival to hospital discharge occurred in 3.8% after conventional CPR, 2.7% after COCPR, and 4.0% after no CPR (p = 0.85). The proportion of patients receiving COCPR was much lower in the cohort of OHCA from respiratory causes (8.3%) than for those with presumed cardiac OHCA (18.0%; p < 0.001).

Conclusions

In the setting of a campaign endorsing lay rescuer COCPR for cardiac OHCA, bystanders were less likely to perform COCPR on OHCA victims who might benefit from rescue breathing.     

Cardiac arrest due to drowning—Changes over time and factors of importance for survival

Aim

To evaluate changes in characteristics and survival over time in out-of-hospital cardiac arrest (OHCA) due to drowning and describe factors of importance for survival.

Method

Retrospectively reported and treated drowning cases reported to the Swedish OHCA registry between 1990 and 2012, n = 529. The data were clustered into three seven-year intervals for comparisons of changes over time.

Results

There were no changes in age, gender, witnessed status, shockable rhythm or place of OHCA during the time periods. Bystander CPR increased over time, 59% in interval 1992–1998, versus 74% in interval 2006–2012 (p = 0.005). There was a decrease in delay between OHCA and calling for the Emergency Medical Service (EMS) over the years, while calling for the EMS to arrival increased in terms of time. Survival to hospital admission appears to have increased over the years (p = 0.009), whereas survival to one month did not change significantly over time. In a multivariate analysis, witnessed status, female gender, bystander CPR, place–home and EMS response time were associated with survival to hospital admission. For survival to one month, place, age, shockable rhythm and logarithmised delay from calling for an ambulance to arrival were of significance for survival.

Conclusion

In OHCA due to drowning, over a period of 20 years, bystanders have called for help at an earlier stage and administered CPR more frequently in the past few years. Survival to hospital admission has increased, while shockable rhythm and early arrival of the EMS appear to be the most important factors for survival to one month.     

Are trained individuals more likely to perform bystander CPR? An observational study

Background

This study aimed to evaluate the association of cardiopulmonary resuscitation (CPR) training with bystander resuscitation performance and patient outcomes after out-of-hospital cardiac arrest (OHCA).

Methods

This was a prospective, population-based cohort study of all persons aged 18 years or older with OHCA of presumed intrinsic origin and their rescuers from January through December 2008 in Takatsuki, Osaka prefecture, Japan. Data on resuscitation of OHCA patients were obtained by emergency medical service (EMS) personnel in charge based on the Utstein style. Rescuers’ characteristics including experience of CPR training were obtained by EMS personnel interview on the scene. The primary outcome was the attempt of bystander CPR.

Results

Data were collected for 120 cases out of 170 OHCAs of intrinsic origin. Among the available cases, 60 (50.0%) had previous CPR training (trained rescuer group). The proportion of bystander CPR was significantly higher in the trained rescuer group than in the untrained rescuer group (75.0% and 43.3%; p = 0.001). Bystanders who had previous experience of CPR training were 3.40 times (95% confidence interval 1.31-8.85) more likely to perform CPR compared with those without previous CPR training. The number of patients with neurologically favorable one-month survival was too small to evaluate statistical difference between the groups (2 [3.3%] in the trained rescuer group versus 1 [1.7%] in the untrained rescuer group; p = 0.500).

Conclusions

People who had experienced CPR training had a greater tendency to perform bystander CPR than people without experience of CPR training. Further studies are needed to prove the effectiveness of CPR training on survival.     

Systematic downloading and analysis of data from automated external defibrillators used in out-of-hospital cardiac arrest

Background

Valuable information can be retrieved from automated external defibrillators (AEDs) used in victims of out-of-hospital cardiac arrest (OHCA). We describe our experience with systematic downloading of data from deployed AEDs. The primary aim was to compare the proportion of shockable rhythm from AEDs used by laypersons with the corresponding proportion recorded by the Emergency Medical Services (EMS) on arrival.

Methods

In a 20-month study, we collected data on OHCAs in the Capital Region of Denmark where an AED was deployed prior to arrival of EMS. The AEDs were brought to the emergency medical dispatch centre for data downloading and rhythm analysis. Patient data were retrieved from the medical records from the admitting hospital, whereas data on EMS rhythm analyses were obtained from the Danish Cardiac Arrest Register between 2001 and 2010.

Results

A total of 121 AEDs were deployed, of which 91 cases were OHCAs with presumed cardiac origin. The prevalence of initial shockable rhythm was 55.0% (95% CI [44.7–64.8%]). This was significantly greater than the proportion recorded by the EMS (27.6%, 95% CI [27.0–28.3%], p < 0.0001). Shockable arrests were significantly more likely to be witnessed (92% vs. 34%, p < 0.0001) and the bystander CPR rate was higher (98% vs. 85%, p = 0.04). More patients with initial shockable rhythm achieved return of spontaneous circulation upon hospital arrival (88% vs. 7%, p < 0.0001) and had higher 30-day survival rate (72% vs. 5%, p < 0.0001).

Conclusion

AEDs used by laypersons revealed a higher proportion of shockable rhythms compared to the EMS rhythm analyses.     

Comparison of methods for the determination of cardiopulmonary resuscitation chest compression fraction

Objective

While cardiopulmonary resuscitation (CPR) chest compression fraction (CCF) is associated with out-of-hospital cardiac arrest (OHCA) outcomes, there is no standard method for the determination of CCF. We compared nine methods for calculating CCF.

Methods

We studied consecutive adult OHCA patients treated by Alabama Emergency Medical Services (EMS) agencies of the Resuscitation Outcomes Consortium (ROC) during January 1, 2010 to October 28, 2010. Paramedics used portable cardiac monitors with real-time chest compression detection technology (LifePak 12, Physio-Control, Redmond, WA). We performed both automated CCF calculation for the entire care episode as well as manual review of CPR data in 1-min epochs, defining CCF as the proportion of each treatment interval with active chest compressions. We compared the CCF values resulting from 9 calculation methods: (1) mean CCF for the entire patient care episode (automated calculation by manufacturer software), (2) mean CCF for first 3 min of patient care, (3) mean CCF for first 5 min, (4) mean CCF for first 10 min, (5) mean CCF for the entire episode except first 5 min, (6) mean CCF for last 5 min, (7) mean CCF from start to first shock, (8) mean CCF for the first half of resuscitation, and (9) mean CCF for the second half of resuscitation. We compared CCF for Methods 2–9 with Method 1 using paired t-tests with a Bonferroni-adjusted p-value of 0.006 (99.5% confidence intervals).

Results

Among 102 adult OHCA, patient demographics were: mean age 60.3 years (SD 20.8 years), African American 56.9%, male 63.7%, and shockable ECG rhythm 23.5%. Mean CPR duration was 728 s (95% CI: 647–809 s). Mean CCF for the 9 CCF calculation methods were: (1) 0.587%; (2) 0.526%; (3) 0.541%; (4) 0.566%; (5) 0.562%; (6) 0.597%; (7) 0.530%; (8) 0.550%; and (9) 0.590%. Compared with Method 1, Method 7 CCF (start to first shock) was slightly lower (−0.057; 99.5% CI: −0.100 to −0.014). There were no other statistically significant CCF differences (range: −0.054 to 0.013). Correlation between CCF 2–9 and CCF varied (ρ = 0.48–0.85).

Conclusion

CCF varies minimally with different calculation methods. Automated CCF determination may prove sufficient for evaluating CPR quality.     

Regionalisation of out-of-hospital cardiac arrest care for patients without prehospital return of spontaneous circulation

Study objectives

The aim of this study was to evaluate the risk of prolonged transportation against the benefit of treatment in high-volume centres for out-of-hospital cardiac arrest (OHCA) patients without prehospital return of spontaneous circulation (ROSC).

Methods

This study used a nationwide EMS-assessed OHCA database (2006–2008). Patients with cardiac aetiology were selected from the registry. A high-volume centre was defined as a hospital that received an average of more than 33 cases per year. OHCA patients without prehospital ROSC were divided into subgroups according to their destination (high-volume centre vs. low-volume centre) and transport interval. The rates of survival to discharge were compared among these groups using multivariate logistic regression analysis.

Results

During the study period, 54,499 OHCA patients were assessed by EMS in Korea. Of these patients, prehospital resuscitation was attempted for 29,345 patients with presumed cardiac origin. After excluding cases with inappropriate time data, 27,662 cases were selected for further analysis. 15,885 (57.4%) patients were transported to low-volume centres while the rest were transported to high-volume centres. The rate of survival to discharge was 1.43% and 4.78%, respectively. A multivariate analysis indicated that even with a longer transport interval (TI)(TI 5–9 min vs. TI 0–4 min), the high-volume centres presented a better overall outcome.

Conclusion

A higher rate of survival to discharge was demonstrated when OHCA patients without prehospital ROSC were transported to high-volume rather than low-volume centres. The rate was still significantly higher when the transportation time was longer compared with that of low-volume centres.     

Validity of reported data in the Swedish Cardiac Arrest Register in selected parts in Sweden

Aim

To describe differences and similarities between reported and non-reported data in the Swedish Cardiac Arrest Register in selected parts in Sweden.

Methods

Prospective and retrospective data for treated OHCA patients in Sweden, 2008–2010, were compared in the Swedish Cardiac Arrest Register. Data were investigated in three Swedish counties, which represented one third of the population. The recording models varied. Prospective data are those reported by the emergency medical service (EMS) crews, while retrospective data are those missed by the EMS crews but discovered afterwards by cross-checking with the local ambulance register.

Result

In 2008–2010, the number of prospectively (n = 2398) and retrospectively (n = 800) reported OHCA cases was n = 3198, which indicates a 25% missing rate.When comparing the two groups, the mean age was higher in patients who were reported retrospectively (69 years vs. 67 years; p = 0.003). There was no difference between groups with regard to gender, time of day and year of OHCA, witnessed status or initial rhythm. Bystander cardiopulmonary resuscitation (CPR) was more frequent among patients who were reported prospectively (65% vs. 60%; p = 0.023), whereas survival to one month was higher among patients who were reported retrospectively (9.2% vs. 11.9%; p = 0.035).

Conclusion

Among 3198 cases of OHCA in three counties in Sweden, 800 (25%) were not reported prospectively by the EMS crews but were discovered retrospectively as missing cases. Patients who were reported retrospectively differed from prospectively reported cases by being older, having less frequently received bystander CPR but having a higher survival rate. Our data suggest that reports on OHCA from national quality registers which are based on prospectively recorded data may be influenced by selection bias.     

Eleven years of experience with extracorporeal cardiopulmonary resuscitation for paediatric patients with in-hospital cardiac arrest

Purpose

The study aims to describe 11 years of experience with extracorporeal cardiopulmonary resuscitation (ECPR) for in-hospital paediatric cardiac arrest in a university affiliated tertiary care hospital.

Methods

Paediatric patients who received extracorporeal membrane oxygenation (ECMO) during active extracorporeal cardiopulmonary resuscitation (ECPR) at our centre from 1999 to 2009 were included in this retrospective study. The results from three different cohorts (1999–2001, 2002–2005 and 2006–2009) were compared. Survival rates and neurological outcomes were analysed. Favourable neurological outcome was defined as paediatric cerebral performance categories (PCPC) 1, 2 and 3.

Results

We identified 54 ECPR events. The survival rate to hospital discharge was 46% (25/54), and 21 (84%) of the survivors had favourable neurological outcomes.The duration of CPR was 39 ± 17 min in the survivors and 52 ± 45 min in the non-survivors (p = NS). The patients with pure cardiac causes of cardiac arrest had a survival rate similar to patients with non-cardiac causes (47% (18/38) vs. 44% (7/16), p = NS).The non-survivors had higher serum lactate levels prior to ECPR (13.4 ± 6.4 vs. 8.8 ± 5.1 mmol/L, p < 0.01) and more renal failure after ECPR (66% (19/29) vs. 20% (5/25), p < 0.01).The patients resuscitated between 2006 and 2009 had shorter durations of CPR (34 ± 13 vs. 78 ± 76 min, p = 0.032) and higher rates of survival (55% (16/29) vs. 0% (0/8), p = 0.017) than those resuscitated between 1999 and 2002.

Conclusions

In our single-centre experience with ECPR for paediatric in-hospital cardiac arrest, the duration of CPR has become shorter and outcomes have improved in recent years. Higher pre-ECPR lactate levels and the presence of post-ECPR renal failure were associated with increased mortality. The presence of non-cardiac causes of cardiac arrest did not preclude successful ECPR outcomes. The duration of CPR was not significantly associated with poor outcomes in this study.