Out-of-hospital cardiac arrests in young adults in Melbourne, Australia

Background

Characteristics and outcomes of out-of-hospital cardiac arrest (OHCA) in young adults are not well described in Australia.

Methods

A 10-year retrospective case review of all OHCA in young adults (aged 16-39) and not witnessed by EMS, was performed using data from the Victorian Ambulance Cardiac Arrest Registry (VACAR).

Results

Between 2000 and 2009 there were 30,006 adult cardiac arrests of which 3912 (13%) were in this age group. The median (IQR) age was 30 (25-35) years for both sexes with a 3:1 male to female ratio. Overdose was the most common precipitant (33.5%) followed by presumed cardiac (20%). Bystander CPR occurred in 21.2%, EMS median response time was 7 min and resuscitation was attempted in 36% of OHCAs. The presenting rhythm was asystole in 84.6%, PEA in 8.8% and VF/VT in 6.6%. Survival to hospital discharge, for all cause OHCA where resuscitation was attempted, was similar for young adult and older adults (8.8% vs 8.4%, p = 0.2). However, for presumed cardiac aetiology OHCA, young adults had a greater proportion of survivors (14.8% vs 9.0%, p < 0.001). Cardiac arrest with shockable rhythm (VF/pulseless VT) had a survival rate of 31.2% for young adults compared to 18.5% for older adults (p < 0.001).

Conclusion

Survival to hospital discharge rates from OHCA due to a ‘presumed cardiac’ precipitant in young adults is much better than older adults, however, all cause OHCA survival is similar. Multi agency novel upstream preventive strategies aimed at tackling drug overdose may reduce this aetiology of OHCA and save lives.     

Changing EMS dispatcher CPR instructions to 400 compressions before mouth-to-mouth improved bystander CPR rates

Background

To examine the impact of changing dispatcher CPR instructions (400 compressions: 2 breaths, followed by 100:2 ratio) on rates of bystander CPR and survival in adults with presumed cardiac out-of-hospital arrest (OHCA) in Melbourne, Australia.

Methods

The Victorian Ambulance Cardiac Arrest Registry (VACAR) was searched for OHCA where Emergency Medical Services (EMS) attempted CPR between August 2006 and August 2009. OHCA included were: (1) patients aged ≥18 years old; (2) presumed cardiac etiology; and (3) not witnessed by EMS.

Results

For the pre- and post-study periods, 1021 and 2101 OHCAs met inclusion criteria, respectively. Rates of bystander CPR increased overall (45-55%, p < 0.001) and by initial rhythm (shockable 55-70%, p < 0.001 and non-shockable 40-46%, p = 0.01). In VF/VT OHCA, there were improvements in the number of patients arriving at hospital with a return of spontaneous circulation (ROSC) (48-56%, p = 0.02) and in survival to hospital discharge (21-29%, p = 0.002), with improved outcomes restricted to patients receiving bystander CPR. After adjusting for factors associated with survival, the period of time following the change in CPR instructions was a significant predictor of survival to hospital discharge in VF/VT patients (OR 1.57, 95% CI: 1.15-2.20, p = 0.005).

Conclusion

Following changes to dispatcher CPR instructions, significant increases were seen in rates of bystander CPR and improvements were seen in survival in VF/VT patients who received bystander CPR, after adjusting for factors associated with survival.     

Cardiac arrest outcomes before and after the 2005 resuscitation guidelines implementation: evidence of improvement?

Background

Previous studies have reported improvements in out-of-hospital cardiac arrest (OHCA) outcomes with the introduction of the 2005 cardiopulmonary resuscitation guidelines however they have not adjusted for underlying trends in OHCA survival. We compare outcomes before and after the 2005 guideline changes adjusting for underlying trends in OHCA survival.

Methods

The Victorian Ambulance Cardiac Arrest Registry (VACAR) was searched for adult (≥16 years) OHCA of presumed cardiac aetiology, unwitnessed by paramedics with attempted resuscitation. Outcomes for OHCA occurring between 2003 and 2005 were compared with 2007-2009. Segmented regression analysis of interrupted time series data was performed, adjusting for known predictors, to examine changes in survival to hospital and survival to hospital discharge.

Results

For the pre- and post- guideline periods there were 3115 and 3248 OHCAs, respectively. Asystole increased as presenting rhythm (33-43%, p < 0.001) as did median EMS response times (7.1-7.8 min, p < 0.001) over the two periods. VF/VT arrests decreased (40-35.5%, p = 0.001) as did bystander witnessed arrests (63-59%, p = 0.002). On univariate analysis survival to hospital discharge improved between the two periods (9.4-11.8%, p = 0.002) due to improved outcomes in VF/VT (19-28%, p < 0.001). Segmented regression analysis of interrupted time series data showed improvement in the rate of survival to get to hospital for shockable and non-shockable rhythms [OR (95% CI) = 1.54 (1.10-2.15, p = 0.01) and 1.45 (1.10-2.00, p = 0.02), respectively] following implementation of the guidelines however survival to hospital discharge did not improve [OR = 1.07 (0.70-1.62, p = 0.70) and 1.40 (0.69-2.85, p = 0.40), respectively].

Conclusions

OHCA outcomes have improved since introduction of the 2005 CPR guidelines, but multivariable segmented regression analysis adjusting for pre-existing trends in survival suggests that this improvement may not be due to implementation of the 2005 resuscitation guidelines.     

Improving outcome after out-of-hospital cardiac arrest by strengthening weak links of the local Chain of Survival; quality of advanced life support and post-resuscitation care

Background

Survival after out-of-hospital cardiac arrest (OHCA) depends on a well functioning Chain of Survival. We wanted to assess if targeted attempts to strengthen the weak links of our local chain; quality of advanced life support (ALS) and post-resuscitation care, would improve outcome.

Materials and methods

Utstein data from all OHCAs in Oslo during three distinct 2-year time periods 1996-1998, 2001-2003 and 2004-2005 were collected. Before the second period the local ALS guidelines changed with increased focus on good quality chest compressions with minimal pauses, while standardized post-resuscitation care including goal directed therapy with therapeutic hypothermia and percutaneous coronary intervention was added in the third period. Additional a priori sub-group analyses of arrests with cardiac aetiology as well as bystander witnessed ventricular fibrillation/tachycardia (VF/VT) arrests with cardiac aetiology were performed.

Results

ALS was attempted in 454, 449, and 417 patients with OHCA in the first, second and last time period, respectively. From the first to the third period VF/VT arrests declined (40% vs. 33%, p = 0.039) and fewer arrests were witnessed (80% vs. 72%, p = 0.022) and response intervals increased (7 ± 4 to 9 ± 4 min, p < 0.001). Overall survival increased from 7% (first period) to 13% (last period), p = 0.002, and survival in the sub-group of bystander witnessed VF/VT arrests with cardiac aetiology increased from 15% (first period) to 35% (last period), p = 0.001.

Conclusions

Survival after OHCA was increased after improving weak links of our local Chain of Survival, quality of ALS and post-resuscitation care.     

Mobile phone technology identifies and recruits trained citizens to perform CPR on out-of-hospital cardiac arrest victims prior to ambulance arrival

Aim

In a two-parted study, evaluate a new concept were mobile phone technology is used to dispatch lay responders to nearby out-of-hospital cardiac arrests (OHCAs).

Methods

Mobile phone positioning systems (MPS) can geographically locate selected mobile phone users at any given moment. A mobile phone service using MPS was developed and named Mobile Life Saver (MLS). Simulation study: 25 volunteers named mobile responders (MRs) were connected to MLS. Ambulance time intervals from 22 consecutive OHCAs in 2005 were used as controls. The MRs randomly moved in Stockholm city centre and were dispatched to simulated OHCAs (identical to controls) if they were within a 350 m distance. Real life study: during 25 weeks 1271-1801 MRs trained in CPR were connected to MLS. MLS was activated at the dispatch centre in parallel with ambulance dispatch when an OHCA was suspected. The MRs were dispatched if they were within 500 m from the suspected OHCA.

Results

Simulation study: mean response time for the MRs compared to historical ambulance time intervals was reduced by 2 min 20 s (44%), p < 0.001, (95% CI, 1 min 5 s - 3 min 35 s). The MRs reached the simulated OHCA prior to the historical control in 72% of cases. Real life study: the MLS was triggered 92 times. In 45% of all suspected and in 56% of all true OHCAs the MRs arrived prior to ambulance. CPR was performed by MRs in 17% of all true OHCAs and in 30% of all true OHCAs if MRs arrived prior to ambulance.

Conclusion

Mobile phone technology can be used to identify and recruit nearby CPR-trained citizens to OHCAs for bystander CPR prior to ambulance arrival.     

Out-of-hospital cardiac arrest frequency and survival: Evidence for temporal variability

Aim

Some cardiac phenomena demonstrate temporal variability. We evaluated temporal variability in out-of-hospital cardiac arrest (OHCA) frequency and outcome.

Methods

Prospective cohort study (the Resuscitation Outcomes Consortium) of all OHCA of presumed cardiac cause who were treated by emergency medical services within 9 US and Canadian sites between 12/1/2005 and 02/28/2007. In each site, Emergency Medical System records were collected and analyzed. Outcomes were individually verified by trained data abstractors.

Results

There were 9667 included patients. Median age was 68 (IQR 24) years, 66.7% were male and 8.3% survived to hospital discharge. The frequency of cardiac arrest varied significantly across time blocks (p < 0.001). Compared to the 0001-0600 hourly time block, the odds ratios and 95% CIs for the occurrence of OHCA were 2.02 (1.90, 2.15) in the 0601-1200 block, 2.01 (1.89, 2.15) in the 1201-1800 block, and 1.73 (1.62, 1.85) in the 1801-2400 block. The frequency of all OHCA varied significantly by day of week (p = 0.03) and month of year (p < 0.001) with the highest frequencies on Saturday and during December. Survival to hospital discharge was lowest when the OHCA occurred during the 0001-0600 time block (7.3%) and highest during the 1201-1800 time block (9.6%). Survival was highest for OHCAs occurring on Mondays (10.0%) and lowest for those on Wednesdays (6.8%) (p = 0.02).

Conclusion

There is temporal variability in OHCA frequency and outcome. Underlying patient, EMS system and environmental factors need to be explored to offer further insight into these observed patterns.     

Pediatric out-of-hospital cardiac arrest in Korea: A nationwide population-based study

Study objectives

Our objective was to describe the incidence and demographics of pediatric out-of-hospital cardiac arrest (OHCA) in Korea.

Methods

We identified non-traumatic OHCA patients aged less than 20 years from a Korean nationwide OHCA registry (2006-2007). Data from emergency medical service (EMS) run-sheets and hospital records were reviewed. We excluded cases with unknown hospital outcomes. Patient characteristics, treatment by EMS, and outcomes were compared by age groups: infant (<1 year), children (1-11 years), and adolescents (12-19 years).

Results

A total of 971 patients including infants (n = 299, 30.8%), children (n = 305, 31.4%), and adolescents (n = 367, 37.8%) met inclusion criteria. The incidence of pediatric OHCA was 4.2 per 100,000 person-years (67.1 in infants, 2.5 in children, and 3.5 in adolescents). The rate of cardiopulmonary resuscitation administered was 82.1% (infants 80.6%, children 82.0%, and adolescent 83.4%). The rate of applying automated external defibrillators and advanced airway management (endotracheal intubation or laryngeal mask airway), was only 4.1% and 2.5%, respectively. 7.4% showed ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT) in the initial ECG. Survival to hospital discharge for all pediatric OHCA was 4.9% (2.9% for infants, 4.7% for children, and 7.2% of adolescents). For EMS-treated pediatric OHCA or patients with VF or pulseless VT, the rate was 5.0% and 31.6%, respectively.

Conclusion

Incidence and hospital outcomes in pediatric OHCA in Korea were comparable to other population-based nationwide reports.     

Esophageal temperature after out-of-hospital cardiac arrest: An observational study

Introduction

Out-of-hospital cardiac arrest (OHCA) is a significant cause of death and severe neurological disability. The only post-return of spontaneous circulation (ROSC) therapy shown to increase survival is mild therapeutic hypothermia (MTH). The relationship between esophageal temperature post OHCA and outcome is still poorly defined.

Methods

Prospective observational study of all OHCA patients admitted to a single centre for a 14-month period (1/08/2008 to 31/09/2009). Esophageal temperature was measured in the Emergency Department and Intensive Care Unit (ICU). Selected patients had pre-hospital temperature monitoring. Time taken to reach target temperature after ROSC was recorded, together with time to admission to the Emergency Department and ICU.

Results

164 OHCA patients were included in the study. 105 (64.0%) were pronounced dead in the Emergency Department. 59 (36.0%) were admitted to ICU for cooling; 40 (24.4%) died in ICU and 19 (11.6%) survived to hospital discharge. Patients who achieved ROSC and had esophageal temperature measured pre-hospital (n = 29) had a mean pre-hospital temperature of 33.9 °C (95% CI 33.2-34.5). All patients arriving in the ED post OHCA had a relatively low esophageal temperature (34.3 °C, 95% CI 34.1-34.6). Patients surviving to hospital discharge were warmer on admission to ICU than patients who died in hospital (35.7 °C vs 34.3 °C, p < 0.05). Patients surviving to hospital discharge also took longer to reach T_targ than non-survivors (2 h 48 min vs 1 h 32 min, p < 0.05).

Conclusions

Following OHCA all patients have esophageal temperatures below normal in the pre-hospital phase and on arrival in the Emergency Department. Patients who achieve ROSC following OHCA and survive to hospital discharge are warmer on arrival in ICU and take longer to reach target MTH temperatures compared to patients who die in hospital. The mechanisms of action underlying esophageal temperature and survival from OHCA remain unclear and further research is warranted to clarify this relationship.     

Assessment of outcomes and differences between in- and out-of-hospital cardiac arrest patients treated with cardiopulmonary resuscitation using extracorporeal life support

Aim

Cardiopulmonary resuscitation (CPR) using extracorporeal life support (ECLS) for in-hospital cardiac arrest (IHCA) patients has been assigned a low-grade recommendation in current resuscitation guidelines. This study compared the outcomes of IHCA and out-of-hospital cardiac arrest (OHCA) patients treated with ECLS.

Methods

A total of 77 patients were treated with ECLS. Baselines characteristics and outcomes were compared for 38 IHCA and 39 OCHA patients.

Results

The time interval between collapse and starting ECLS was significantly shorter after IHCA than after OHCA (25 (21-43) min versus 59 (45-65) min, p < 0.001). The weaning rate from ECLS (61% versus 36%, p = 0.03) and 30-day survival (34% versus 13%, p = 0.03) were higher for IHCA compared with OHCA patients. IHCA patients had a higher rate of favourable neurological outcome compared to OHCA patients, but the difference was not statistically significant (26% versus 10%, p = 0.07). Kaplan-Meier analysis showed improved 30-day and 1-year survival for IHCA patients treated with ECLS compared to OHCA patients who had ECLS. However, multivariate stepwise Cox regression model analysis indicated no difference in 30-day (odds ratio 0.94 (95% confidence interval 0.68-1.27), p = 0.67) and 1-year survival (0.99 (0.73-1.33), p = 0.95).

Conclusion

CPR with ECLS led to more favourable patient outcomes after IHCA compared with OHCA in our patient group. The difference in outcomes for ECLS after IHCA and OHCA disappeared after adjusting for patient factors and the time delay in starting ECLS.     

Epidemiology and outcomes of poisoning-induced out-of-hospital cardiac arrest

Objectives

We aimed to describe and compare the epidemiologic features and outcomes among patients with poisoning-induced out-of-hospital cardiac arrests (POHCAs) according to causative agent groups.

Methods

We identified emergency medical service (EMS)-treated POHCA patients from a nationwide OHCA registry between 2006 and 2008, which was derived from EMS run sheets and followed by hospital record review. Utstein elements were collected and hospital outcomes (survival to admission and to discharge) were measured. We compared risk factors and outcomes according to the main poisons. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated from a multivariate logistic regression model for hospital outcomes.

Results

The total number of non-cardiac aetiology OHCAs was 20,536. Of these, the number of EMS-assessed and EMS-treated POHCAs was 900 (4.4%). For EMS-treated POHCAs, insecticides (n = 111, 15.5%) including organophosphate and carbamates; herbicides (n = 94, 13.2%); unknown pesticides (n = 142, 19.9%); non-pesticide drugs (n = 120, 16.8%); and unknown poisons (n = 247, 6%) were identified. The survival to admission rate was 22.5% for insecticides, 3.2% for herbicides, 16.2% for unknown pesticides, 16.7% for non-pesticides and 11.3% for the unknown group. The survival to discharge rates were 9.9% for insecticides, 0.0% for herbicides, 2.1% for unknown pesticides, 3.3% for non-pesticides and 3.2% for the unknown group. The adjusted OR for each group for survival to admission was significantly lower when compared with insecticides: herbicides (OR = 0.11, 95% CI = 0.03-0.44), non-pesticide drugs (OR = 0.28, 95% CI = 0.13-0.61) and unknown group (OR = 0.40, 95% CI = 0.21-0.76). The adjusted OR for each group for survival to discharge was significantly lower when compared with insecticides: herbicides (OR < 0.01, 95% CI < 0.01 or >99.9), unknown pesticides (OR = 0.23, 95% CI = 0.0.06-0.87), non-pesticide drugs (OR = 0.14, 95% CI = 0.04-0.54) and unknown group (OR = 0.30, 95% CI = 0.11-0.83).

Conclusion

Using a nationwide OHCA registry, we found that poisonings were responsible for 4.4% of OHCAs of a non-cardiac aetiology. Ingestion of insecticides including organophosphate and carbamate was associated with more favourable outcomes.     

Incidence and outcomes of out-of-hospital cardiac arrest with shock-resistant ventricular fibrillation: Data from a large population-based cohort

Background

The increasing survival rates after out-of-hospital cardiac arrests (OHCA) are due mainly to improvements in the first 3 steps of the chain of survival. The aim of this study was to describe the temporal trends of OHCA incidence and outcomes with shock-resistant ventricular fibrillation (VF) requiring advanced life support procedures.

Methods

All our subjects were persons aged 18 years or more who had suffered OHCA of presumed cardiac etiology, were witnessed by bystanders, treated by emergency medical service (EMS), and had VF as initial rhythm. Our study was conducted in Osaka Prefecture, Japan from May 1, 1998 through December 31, 2006. Data were collected by EMS personnel using an Utstein-style database. We evaluated the temporal trends of incidence and outcomes of shock-resistant VF.

Results

During the study period, there were 8782 witnessed OHCA cases of presumed cardiac etiology. Among them, 1733 had VF as an initial rhythm, 392 of whom were shock-resistant. While the age-adjusted annual incidence of witnessed VF increased from 2.0 to 3.3 per 100,000 inhabitants, that of shock-resistant VF underwent little change during the study period. The proportion of shock-resistant VF among witnessed VF decreased from 37.0% to 19.0%. Neurologically intact 1-month survival rates after shock-resistant VF remained low at 5.6% even in 2006.

Conclusion

The actual incidence of shock-resistant VF has remained unchanged, and their outcomes continue to be dismal. Further efforts are required to reduce the mortality rates of such shock-resistant VF to achieve improved survival after OHCA.     

Factors influencing the decision to ICD implantation in survivors of OHCA and its influence on long term survival

Background

Knowledge is insufficient of the long-term benefit of an implantable cardioverter defibrillator (ICD) after out of hospital cardiac arrest (OHCA).

Aim

To describe the use and factors of importance for outcome in relation to ICD use among survivors of ventricular fibrillation (VF).

Methods

In consecutive patients discharged alive after OHCA in Gothenburg between 1988 and 2008 the long-term prognosis was followed.

Results

In all, there were 5443 OHCAs of which 1489 (27%) were hospitalized alive. Of those, 495 (33%) were discharged alive, of which 390 (79%) had shockable rhythm. The use of ICDs increased, but only 58 of 390 (15%) had an ICD. Among patients who received an ICD, the 2-year mortality was 2%, versus 25% of those who did not (p < 0.0001).In follow-up (mean 5.5 years; maximum 10 years), the use of an ICD showed a borderline association with mortality (adjusted hazard ratio 0.49; 95% confidence interval, 024–1.01; p = 0.052).Patients who had ICD were younger and had better cerebral function compared with patients without. Predictors for mortality were cerebral function at discharge, age, history of heart failure and myocardial infarction and no coronary angiography during hospitalization.

Conclusion

Among survivors of OHCA caused by VT/VF who had ICD during hospitalization only 2% died during the subsequent 2 years. The use of ICDs was low but increasing. Factors of importance for mortality were cerebral function at the time of discharge, age, history of heart failure and myocardial infarction and no coronary angiography during hospitalization.     

Paediatric 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 paediatric traumatic OHCA.

Methods

The Victorian Ambulance Cardiac Arrest Registry (VACAR) was used to identify all trauma related cases of OHCA in patients aged less than 16 years of age. Cases were linked with their coronial findings.

Results

Between 2000 and 2009, EMS attended 33,722 OHCAs including 2187 adult traumatic OHCAs. There were 538 (1.6%) OHCAs in children less than 16 years of age of which n = 64 were due to trauma. The median age (IQR) of paediatric traumatic OHCA was 7 (4.5–13) years and 44 were male (69%). Bystander CPR was performed in 22 cases (34.4%). The first recorded rhythm by EMS was asystole seen in 42 (66%), PEA in 14 (22%) cases and VF in 2 cases (3%). Cardiac output was present in 7 (11%) cases who subsequently had an EMS witnessed OHCA. EMS attempted resuscitation in 35 (55%) patients of whom 7 (20%) achieved ROSC and were transported, and 1 (3%) survived to hospital discharge with severe neurological sequelae; 14(40%) were transported with CPR of whom none survived. Coronial cause of death was multiple injuries in 35%, head injury in 33%, head and neck injury in 10%, chest injuries in 10% and other causes (12%).

Conclusions

Traumatic aetiology of OHCA when compared to the incidence of adult traumatic OHCAs is uncommon. Resuscitation efforts are seldom effective and associated with poor neurological outcome.     

Impact of transport to critical care medical centers on outcomes after out-of-hospital cardiac arrest

Background

Post-resuscitation care has emerged as an important predictor of survival from out-of-hospital cardiac arrest (OHCA). In Japan, selected hospitals are certified as Critical Care Medical Centers (CCMCs) based on their ability and expertise.

Hypothesis

Outcome after OHCA is better in patients transported to a CCMC compared a non-critical care hospital (NCCH).

Materials and methods

Adults with OHCA of presumed cardiac etiology, treated by emergency medical services systems, and transported in Osaka from January 1, 2005 to December 31, 2007 were registered using a prospective Utstein style population cohort database. Primary outcome measure was 1 month neurologically favorable survival (CPC ≤ 2). Outcomes of patients transported to CCMC were compared with patients transported to NCCH using multiple logistic regressions and stratified on the basis of stratified field ROSC.

Results

10,383 cases were transported. Of these, 2881 were transported to CCMC and 7502 to NCCH. Neurologically favorable 1-month survival was greater in the CCMC group [6.7% versus 2.8%, P < 0.001]. Among patients who were transported to hospital without field ROSC, neurologically favorable outcome was greater in the CCMC group than the NCCH group [1.7% versus 0.5%; adjusted odds ratio (OR), 3.39; 95% confidence interval (CI), 2.17-5.29; P < 0.001]. In the presence of field ROSC, survival was similar between the groups [43% versus 41%; adjusted OR, 1.09; 95% CI, 0.82-1.45; P = 0.554].

Conclusions

Survival after OHCA of presumed cardiac etiology transported to CCMCs was better than those transported to NCCHs. For OHCA patients without field ROSC, transport to a CCMC was an independent predictor for a good neurological outcome.     

Prognostic indicators and outcome prediction model for patients with return of spontaneous circulation from cardiopulmonary arrest: the Utstein Osaka Project

Objective

To determine the most important indicators of prognosis in patients with return of spontaneous circulation (ROSC) following out-of-hospital cardiopulmonary arrest (OHCA) and to develop a best outcome prediction model.

Design and patients

All patients were prospectively recorded based on the Utstein Style in Osaka over a period of 3 years (2005-2007). Criteria for inclusion were a witnessed cardiac arrest, age greater than 17 years, presumed cardiac origin of the arrest, and successful ROSC. Multivariate logistic regression (MLR) analysis was used to develop the best prediction model. The dependent variables were favourable outcome (cerebral-performance category [CPC]: 1-2) and poor outcome (CPC: 3-5) at 1 month after the event. Eight explanatory pre-hospital variables were used concerning patient characteristics and resuscitation. External validation was performed on an independent set of Utstein data in 2007.

Results

Subjects comprised 285 patients in VF and 577 patients with pulseless electrical activity (PEA)/asystole. The percentage of favourable outcomes was 31.9% (91/285) in VF and 5.7% (33/577) in PEA/asystole. The most important prognostic indicators of favourable outcome found by MLR were age (p = 0.10), time from collapse to ROSC (TROSC) (p < 0.01), and presence of pre-hospital ROSC (PROSC) (p = 0.15) for VF and age (p = 0.03), TROSC (p < 0.01), PROSC (p < 0.01), and conversion to VF (p = 0.01) for PEA/asystole. For external validation data, areas under the receiver-operating characteristic curve were 0.867 for VF and 0.873 for PEA/asystole.

Conclusions

A model based on four selected indicators showed a high predictive value for favourable outcome in OHCA patients with ROSC.     

Nifekalant versus lidocaine for in-hospital shock-resistant ventricular fibrillation or tachycardia

Objective

To compare the efficacy and safety of nifekalant, a pure class III anti-arrhythmic drug, and lidocaine in patients with shock-resistant in-hospital ventricular fibrillation (VF) or ventricular tachycardia (VT).

Patients and methods

Between August 2005 and March 2008, we conducted a prospective, two-arm, cluster observational study, in which participating hospitals were pre-registered either to the nifekalant arm or the lidocaine arm. Patients were enrolled if they had in-hospital VF or VT resistant to at least two defibrillation shocks. Congenital or drug-induced long QT syndrome was excluded. The primary end-point was termination of VF or VT with/without additional shock. The secondary end-points were return of spontaneous circulation (ROSC), 1-month survival and survival to hospital discharge. We also assessed the frequency of adverse events, including asystole, pulseless electrical activity and torsade de pointes.

Results

In total, 55 patients were enrolled. After nifekalant, 22 of 27 patients showed termination of VF or VT, as compared with 15 of 28 patients treated with lidocaine with/without additional shock (odds ratio (OR): 3.8; 95% confidence interval (CI): 1.1-13.0; P = 0.03). Twenty-three of 27 patients given nifekalant showed ROSC, as compared with 15 of 28 patients given lidocaine (OR: 5.0; 95% CI: 1.4-18.2; P = 0.01). There was no difference in 1-month survival or survival to hospital discharge between the nifekalant and lidocaine arms. There was a higher incidence of asystole with lidocaine (7 of 28 patients) than with nifekalant (0 of 27 patients) (P = 0.005). Torsade de pointes was not observed.

Conclusion

Nifekalant was more effective than lidocaine for termination of arrhythmia and for ROSC in patients with shock-resistant in-hospital VF or VT (umin-CTR No. UMIN 000001781).     

Resuscitation of out-of-hospital cardiac arrests in residential aged care facilities in Melbourne, Australia

Introduction

CPR in patients in residential aged care facilities (RACF) deserves careful consideration. We examined the characteristics, management and outcomes of out-of-hospital cardiac arrest (OHCA) in RACF patients in Melbourne, Australia.

Methods

The Victorian Ambulance Cardiac Arrest Registry (VACAR) was searched for all OHCAs occurring in RACFs in Melbourne. The characteristics and outcomes were compared to non-RACF patients in the VACAR.

Results

Between 2000 and 2009 there were 30,006 OHCAs, 2350 (7.8%) occurring in a RACF.A shockable rhythm was present in 179 (7.6%) patients on arrival of paramedics of whom bystander CPR had been performed in 118 (66%); 173 (97%) received an EMS attempted resuscitation. ROSC was achieved in 71 (41%) patients and 15 (8.7%) patients survived to leave hospital. Non shockable rhythm was present in 2171 patients (92%) of whom 804 (37%) had an attempted resuscitation by paramedics. ROSC was achieved in 176 patients (22%) and 10 patients (1.2%) were discharged alive. Survival from OHCA occurring in a RACF was less than survival in those aged >70 years of age who suffered OHCA in their own homes (1.8% vs. 4.7%, p = 0.001). On multivariable analysis, witnessed OHCA (OR 3.0, 95% CI 2.4-3.7) and the presence of bystander CPR (OR 4.6, 95% CI 3.7-5.8) was associated with the paramedic decision to resuscitate.

Conclusion

Resuscitation of patients in RACF is not futile. However, informed decisions concerning resuscitation status should be made by patients and their families on entry to a RACF. Where it is appropriate to perform resuscitation, outcomes may be improved by the provision of BLS training and possibly AED equipment to RACF staff.     

Long-term changes in the incidence of out-of-hospital ventricular fibrillation

Aim of the study

To report the long-term changes in the incidence of out-of-hospital ventricular fibrillation (VF), and also to report concurrent changes in the possible explanatory factors for the change.

Methods

This was a retrospective observational study. All bystander-witnessed out-of-hospital cardiac arrests (with a known initial rhythm) in Helsinki, Finland during 1.1.1994-31.12.2007 were included in the study. High (years 1994-1996) and low (2002-2004) incidence periods for VF were defined and compared.

Results

There were 3131 bystander-witnessed out-of-hospital cardiac arrests of which 3118 (99.6%) had a known initial rhythm. During 2000-2007 the annual incidence of bystander witnessed ventricular fibrillation (VF) was 11.6 (95% CI 9.7-13.5) per 100,000 inhabitants. In 1994-1996 VF was 1.8 times more likely than in 2002-2004, after adjustment for several patient related factors and EMS related factors. Arrests with cardiac aetiology became less common, as 54.8% arrests had a cardiac cause in 1994-1996 compared to 45.2% in 2002-2004 (p < 0.001). Of cardiac arrests with cardiac aetiology, 60.6% presented with VF in 1994-1996 compared to 45.7% in 2002-2004 (p < 0.001). There were major changes in the possible explanatory factors during the study period.

Conclusion

The decline in the incidence of out-of-hospital VF seems to have ended, and the annual incidence of VF has stabilised to 11.6 (95% CI 9.7-13.5) per 100,000 inhabitants. During the period of lower incidence of VF, cardiac aetiology caused fewer arrests, and these arrests did not present with VF as often as previously.     

Reduced in-hospital survival rates of out-of-hospital cardiac arrest victims with obstructive pulmonary disease

Aim

Out-of-hospital cardiac arrest (OHCA) due to sustained ventricular tachycardia/fibrillation (VT/VF) is common and often lethal. Patient's co-morbidities may determine survival after OHCA, and be instrumental in post-resuscitation care, but are poorly studied. We aimed to study whether patients with obstructive pulmonary disease (OPD) have a lower survival rate after OHCA than non-OPD patients.

Methods

We performed a community-based cohort study of 1172 patients with non-traumatic OHCA with ECG-documented VT/VF between 2005 and 2008. We compared survival to Emergency Room (ER), to hospital admission, to hospital discharge, and at 30 days after OHCA, of OPD-patients and non-OPD patients, using logistic regression analysis. We also compared 30-day survival of patients who were admitted to hospital, using multivariate logistic regression analysis.

Results

OPD patients (n = 178) and non-OPD patients (n = 994) had comparable survival to ER (75% vs. 78%, OR 0.9 [95% CI: 0.6–1.3]) and to hospital admission (56% vs. 57%, OR 1.0 [0.7–1.4]). However, survival to hospital discharge was significantly lower among OPD patients (21% vs. 33%, OR 0.6 [0.4–0.9]). Multivariate regression analysis among patients who were admitted to hospital (OPD: n = 100, no OPD: n = 561) revealed that OPD was an independent determinant of reduced 30-day survival rate (39% vs. 59%, adjusted OR 0.6 [0.4–1.0, p = 0.035]).

Conclusion

OPD-patients had lower survival rates after OHCA than non-OPD patients. Survival to ER and to hospital admission was not different between both groups. However, among OHCA victims who survived to hospital admission, OPD was an independent determinant of reduced 30-day survival rate.     

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.