A model of survival following pre-hospital cardiac arrest based on the Victorian Ambulance Cardiac Arrest Register

Incidence and Outcomes After Out-of-Hospital Cardiac Arrest at Train Stations in Denmark

BACKGROUND

Following international guidelines, communities have deployed automated external defibrillators at train stations without substantive evidence.

METHODS AND RESULTS

We geocoded public out-of-hospital cardiac arrests (OHCAs) (2016-2020), automated external defibrillators, and train stations. The stations were divided into the following groups according to passenger flow: 1 (0-499), 2 (500-4999), 3 (5000-9999), and 4 (>10 000) passengers per day. Risk ratios (RRs) were calculated using Poisson regression of rates, and odds ratios (ORs) were analyzed through logistic regression. OHCAs at train stations accounted for 102 (2.3%) of 4467 public OHCAs. The incidence rate (IR) and RR for OHCAs were for group 1: IR, 0.02 OHCA per station per year, RR, 1.0 (reference); group 2: IR, 0.07, RR, 4.1 (95% CI, 2.3-7.3); group 3: IR, 0.25, RR, 12.7 (95% CI, 6.2-25.9); and group 4: IR, 0.34, RR, 16.3 (95% CI, 8.6-30.9). Compared with other public OHCAs, OHCAs at train stations were just as likely to receive bystander cardiopulmonary resuscitation (OR, 1.13 [95% CI, 0.60-2.12]). However, they had higher odds of bystander defibrillation (OR, 1.66 [95% CI, 1.06-2.58]), were more likely to achieve return of spontaneous circulation (OR, 1.88 [95% CI, 1.24-2.85]), and survive 30 days (OR, 2.37 [95% CI, 1.57-3.59]).

CONCLUSIONS

The incidence of OHCAs at train stations was associated with passenger flow, with the busiest stations having a 16-fold higher risk of OHCAs than the lowest. OHCAs at train stations had better outcomes compared with other public OHCAs.

Association Between Delays in Time to Bystander CPR and Survival for Witnessed Cardiac Arrest in the United States

BACKGROUND

Prompt initiation of bystander cardiopulmonary resuscitation (CPR) is critical to survival for out-of-hospital cardiac arrest (OHCA). However, the association between delays in bystander CPR and OHCA survival is poorly understood.

METHODS

In this observational study using a nationally representative US registry, we identified patients who received bystander CPR from a layperson for a witnessed OHCA from 2013 to 2021. Hierarchical logistic regression was used to estimate the association between time to CPR (<1 minute versus 2-3, 4-5, 6-7, 8-9, and ≥10-minute intervals) and survival to hospital discharge and favorable neurological survival (survival to discharge with cerebral performance category of 1 or 2 [ie, without severe neurological disability]).

RESULTS

Of 78 048 patients with a witnessed OHCA treated with bystander CPR, the mean age was 63.5±15.7 years and 25, 197 (32.3%) were women. The median time to bystander CPR was 2 (1-5) minutes, with 10% of patients having a≥10-minute delay before initiation of CPR. Overall, 15 000 (19.2%) patients survived to hospital discharge and 13 159 (16.9%) had favorable neurological survival. There was a graded inverse relationship between time to bystander CPR and survival to hospital discharge (P for trend <0.001). Compared with patients who received CPR within 1 minute, those with a time to CPR of 2 to 3 minutes were 9% less likely to survive to discharge (adjusted odds ratio, 0.91 [95% CI, 0.87-0.95]) and those with a time to CPR 4 to 5 minutes were 27% less likely to survive (adjusted odds ratio, 0.73 [95% CI, 0.68-0.77]). A similar graded inverse relationship was found between time to bystander CPR and favorable neurological survival (P for trend <0.001).

CONCLUSIONS

Among patients with witnessed OHCA, there was a dose-response relationship between delays in bystander initiation of CPR and lower survival rates.

A study protocol for a cluster-randomised controlled trial of smartphone-activated first responders with ultraportable defibrillators in out-of-hospital cardiac arrest: The First Responder Shock Trial (FIRST)

Objective

To describe the First Responder Shock Trial (FIRST), which aims to determine whether equipping frequently responding, smartphone-activated (GoodSAM) first responders with an ultraportable AED can increase 30-day survival rates in OHCA.

Methods

The FIRST trial is an investigator-initiated, bi-national (Victoria, Australia and New Zealand), registry-nested cluster-randomised controlled trial where the unit of randomisation is the smartphone-activated (GoodSAM) first responder. High-frequency GoodSAM responders are randomised 1:1 to receive an ultraportable, single-use AED or standard alert procedures using the GoodSAM app.The primary outcome is survival to 30 days. The secondary outcome measures (shockable rhythm, return of spontaneous circulation, event survival, and time to first shock delivery) are routinely collected by OHCA registries in both regions. The trial was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR) (Registration: ACTRN12622000448741) on 22 March 2022.

Results

The trial started in November 2022 and the last patient is expected to be enrolled in November 2024. We aim to detect a 7% increase in the proportion of 30-day survivors, from 9% in patients attended by control responders to 16% in patients attended by responders randomised to the ultraportable AED intervention arm. With 80% power, an alpha of 0.05, a cluster size of 1.5 and a coefficient of variation for cluster sizes of 1, the sample size required to detect this difference is 714 (357 per arm).

Conclusion

The FIRST study will increase our understanding of the potential role of portable AED use by smartphone-activated community responders and their impact on survival outcomes.

Public Out-of-Hospital Cardiac Arrest in Residential Neighborhoods

BACKGROUND

Although one-half of all public out-of-hospital cardiac arrests (OHCAs) occur outside private homes in residential neighborhoods, their characteristics and outcomes remain unexplored.

OBJECTIVES

The authors assessed interventions before ambulance arrival and survival for public OHCA patients in residential neighborhoods.

METHODS

Public OHCAs from Vienna (2018-2021) and Copenhagen (2016-2020) were designated residential neighborhoods or nonresidential areas. Interventions (cardiopulmonary resuscitation [CPR], automated external defibrillator [AED] attached, and defibrillation) and 30-day survival were compared using a generalized estimation equation model adjusted for age and time of day and presented as ORs.

RESULTS

We included 1,052 and 654 public OHCAs from Vienna and Copenhagen, respectively, and 68% and 55% occurred in residential neighborhoods, respectively. The likelihood of CPR, defibrillation, and survival in residential neighborhoods vs nonresidential areas (reference) were as follows: CPR Vienna, 73% vs 78%, OR: 0.78 (95% CI: 0.57-1.06), CPR Copenhagen, 83% vs 90%, OR: 0.54 (95% CI: 0.34-0.88), and CPR combined, 76% vs 84%, OR: 0.70 (95% CI: 0.53-0.90); AED attached Vienna, 36% vs 44%, OR: 0.69 (95% CI: 0.53-0.90), AED attached Copenhagen, 21% vs 43%, OR: 0.33 (95% CI: 0.24-0.48), and AED attached combined, 31% vs 44%, OR: 0.53 (95% CI: 0.42-0.65); defibrillation Vienna, 14% vs 20%, OR: 0.61 (95% CI: 0.43-0.87), defibrillation Copenhagen, 16% vs 36%, OR: 0.35 (95% CI: 0.24-0.51), and defibrillation combined, 15% vs 27%, OR: 0.46 (95% CI: 0.36-0.61); and 30-day survival rate Vienna, 21% vs 26%, OR: 0.84 (95% CI: 0.58-1.20), 30-day survival rate Copenhagen, 33% vs 44%, OR: 0.65 (95% CI: 0.47-0.90), and 30-day survival rate combined, 25% vs 36%, OR: 0.73 (95% CI: 0.58-0.93).

CONCLUSIONS

Two-thirds of public OHCAs occurred in residential neighborhoods with fewer resuscitative efforts before ambulance arrival and lower survival than in nonresidential areas. Targeted efforts to improve early CPR and defibrillation for public OHCA patients in residential neighborhoods are needed.

Telephone-Cardiopulmonary Resuscitation Guided by a Telecommunicator: Design of a Guiding Algorithm for Telecommunicators

BACKGROUND

Out-of-hospital cardiac arrest is considered a global problem. In the last few years, there has been a growing interest in telephone-cardiopulmonary resuscitation guided by a telecommunicator. Indeed, several studies have demonstrated that it increases the chances of survival rate. This study focuses on the key points the operator should follow when performing telephone-cardiopulmonary resuscitation. The main objective of this paper is to design an algorithm to improve the telephone-cardiopulmonary resuscitation response protocol.

METHODS

The available evidence and the areas of uncertainty that have not been previously mentioned in the literature are discussed. All the information has been analyzed by two discussion groups. Later, a consensus was reached among all members. Finally, a response algorithm was designed and implemented in clinical simulation.

RESULTS

All the witnesses were able to recognize the OHCA, call for emergency assistance, follow all the operator's instructions, move the victim, and place their hands in the correct position to perform CPR.

DISCUSSION

The results of the pilot study provide us a basis for further experimental studies using randomization and experimental and control groups.

CONCLUSIONS

No standardized recommendations exist for the operator to perform telephone-guided CPR. For this reason, a response algorithm was designed.

One-year quality-of-life outcomes of cardiac arrest survivors by initial defibrillation provider

OBJECTIVE

To assess the long-term functional and health-related quality-of-life (HRQoL) outcomes for out-of-hospital cardiac arrest (OHCA) survivors stratified by initial defibrillation provider.

METHODS

This retrospective study included adult non-traumatic OHCA with initial shockable rhythms between 2010 and 2019. Survivors at 12 months after arrest were invited to participate in structured telephone interviews. Outcomes were identified using the Glasgow Outcome Scale-Extended (GOS-E), EuroQol-5 Dimension (EQ-5D), 12-Item Short Form Health Survey and living and work status-related questions.

RESULTS

6050 patients had initial shockable rhythms, 3211 (53.1%) had a pulse on hospital arrival, while 1879 (31.1%) were discharged alive. Bystander defibrillation using the closest automated external defibrillator had the highest survival rate (52.8%), followed by dispatched first responders (36.7%) and paramedics (27.9%). 1802 (29.8%) patients survived to 12-month postarrest; of these 1520 (84.4%) were interviewed. 1088 (71.6%) were initially shocked by paramedics, 271 (17.8%) by first responders and 161 (10.6%) by bystanders. Bystander-shocked survivors reported higher rates of living at home without care (87.5%, 75.2%, 77.0%, p<0.001), upper good recovery (GOS-E=8) (41.7%, 30.4%, 30.6%, p=0.002) and EQ-5D visual analogue scale (VAS) ≥80 (64.9%, 55.9%, 52.9%, p=0.003) compared with first responder and paramedics, respectively. After adjustment, initial bystander defibrillation was associated with higher odds of EQ-5D VAS ≥80 (adjusted OR (AOR) 1.56, 95% CI 1.15-2.10; p=0.004), good functional recovery (GOS-E ≥7) (AOR 1.53, 95% CI 1.12-2.11; p=0.009), living at home without care (AOR 1.77, 95% CI 1.16-2.71; p=0.009) and returning to work (AOR 1.72, 95% CI 1.05-2.81; p=0.031) compared with paramedic defibrillation.

CONCLUSION

Survivors receiving initial bystander defibrillation reported better functional and HRQoL outcomes at 12 months after arrest compared with those initially defibrillated by paramedics.

The Impact of Prehospital and Hospital Care on Clinical Outcomes in Out-of-Hospital Cardiac Arrest

Background: In recent years, several actions have been made to shorten the chain of survival in out-of-hospital cardiac arrest (OHCA). These include placing defibrillators in public places, training first responders, and providing dispatcher-assisted CPR (DA-CPR). In this work, we aimed to evaluate the impact of these changes on patients' outcomes, including achieving return of spontaneous circulation (ROSC), survival to discharge, and survival with favorable neurological function. Methods: We retrospectively retrieved data of all calls to the national emergency medical service in Ashdod city, Israel, of individuals who underwent OHCA at the age of 18 and older between the years 2018 and 2021. Data was collected on prehospital and hospital interventions. The association between pre-hospital and hospital interventions to ROSC, survival to discharge, and neurological outcomes was evaluated. Logistic regression was used for multivariable analysis. Results: During the years 2018-2021, there were 1253 OHCA cases in the city of Ashdod. ROSC was achieved in 207 cases (32%), survival to discharge was attained in 48 cases (7.4%), and survival with favorable neurological function was obtained in 26 cases (4%). Factors significantly associated with good prognosis were shockable rhythm, witnessed arrest, DA-CPR, use of AED, and treatment for STEMI. All patients that failed to achieve ROSC outside of the hospital setting had a poor prognosis. Conclusions: This study demonstrates the prognostic role of the initial rhythm and the use of AED in OHCA. Hospital management, including STEMI documentation and catheterization, was also an important prognostication factors. Additionally, when ROSC is not achieved in the field, hospital transfer should be considered.

Risk prediction models for out-of-hospital cardiac arrest outcomes in England

AIMS

The out-of-hospital cardiac arrest (OHCA) outcomes project is a national research registry. One of its aims is to explore sources of variation in OHCA survival outcomes. This study reports the development and validation of risk prediction models for return of spontaneous circulation (ROSC) at hospital handover and survival to hospital discharge.

METHODS AND RESULTS

The study included OHCA patients who were treated during 2014 and 2015 by emergency medical services (EMS) from seven English National Health Service ambulance services. The 2014 data were used to identify important variables and to develop the risk prediction models, which were validated using the 2015 data. Model prediction was measured by area under the curve (AUC), Hosmer-Lemeshow test, Cox calibration regression, and Brier score. All analyses were conducted using mixed-effects logistic regression models. Important factors included age, gender, witness/bystander cardiopulmonary resuscitation (CPR) combined, aetiology, and initial rhythm. Interaction effects between witness/bystander CPR with gender, aetiology and initial rhythm and between aetiology and initial rhythm were significant in both models. The survival model achieved better discrimination and overall accuracy compared with the ROSC model (AUC = 0.86 vs. 0.67, Brier score = 0.072 vs. 0.194, respectively). Calibration tests showed over- and under-estimation for the ROSC and survival models, respectively. A sensitivity analysis individually assessing Index of Multiple Deprivation scores and location in the final models substantially improved overall accuracy with inconsistent impact on discrimination.

CONCLUSION

Our risk prediction models identified and quantified important pre-EMS intervention factors determining survival outcomes in England. The survival model had excellent discrimination.

Comparison of Out-of-Hospital Cardiac Arrests Occurring in Schools and Other Public Locations: A 12-Year Retrospective Study

Objective: Out-of-hospital cardiac arrests (OHCA) in schools and universities are uncommon. However, these institutions must plan and prepare for such events to ensure the best outcomes. To evaluate their preparedness we assessed baseline characteristics, survival outcomes and 12-year trends for OHCA in schools/universities compared to other public locations.Methods: We conducted a retrospective analysis of OHCA in schools/universities and public locations between 2008 and 2019 using Victorian Ambulance Cardiac Arrest Registry data.Results: We included 9,037 EMS attended cases, 131 occurred in schools/universities and 8,906 in public locations. Compared to public locations, a significantly higher proportion of EMS treated cases in schools/universities received bystander cardiopulmonary resuscitation (CPR) (95.5% vs. 78.5%, p < 0.001), public access defibrillation (PAD) (26.1% vs. 9.9%, p < 0.001) and presented in shockable rhythms (69.4% vs. 50.9%, p < 0.001). Unadjusted survival to hospital discharge rates were also significantly higher in schools/universities (39.6% vs. 24.2%, p < 0.001). The long-term unadjusted trends for bystander CPR in schools/universities increased from 91.7% (2008-10) to 100% (2017-19) (p-trend = 0.025), for PAD from 4.2% (2008-10) to 47.5% (2017-19) (p-trend < 0.001) and for survival to hospital discharge from 16.7% (2008-10) to 57.5% (2017-19) (p-trend = 0.004). However, after adjustment for favorable cardiac arrest factors, such as younger age, bystander CPR and PAD, survival was similar between schools/universities and public locations.Conclusion: The majority of OHCA in schools and universities were witnessed and received bystander CPR, however less than half received PAD. Developing site-specific cardiac emergency response plans and providing age appropriate CPR training to primary, secondary and university students would help improve PAD rates.

Effect of gender on out-of-hospital cardiac arrest survival: a registry-based study

OBJECTIVE

The aim of the study was to compare outcomes after out-of-hospital cardiac arrest (OHCA) between comparable female and male OHCA cohorts in a large nationwide registry.

METHODS

This was a national multicentre retrospective, case-control propensity score-matched study based on French National Cardiac Arrest Registry data from 1 July 2011 to 21 September 2017. Female and male survival rates at D30 were compared.

RESULTS

At baseline 66 395 OHCA victims were included, of which 34.3% were women. At hospital admission, survival was 18.2% for female patients and 20.2% for male patients [odds ratio (OR), 1.138 (1.092-1.185)]; at 30 days, survival was 4.3 and 5.9%, respectively [OR, 1.290 (1.191-1.500)]. After matching (14 051 patients within each group), female patients received less advanced life support by mobile medical team (MMT), they also had a longer no-flow duration and shorter resuscitation effort by MMT than male patients. However, 15.3% of female patients vs. 9.1% of male patients were alive at hospital admission [OR, 0.557 (0.517-0.599)] and 3.2 vs. 2.6% at D30 [OR, 0.801 (0.697-0.921)], with no statistically significant difference in neurological outcome [OR, 0.966 (0.664-1.407)].

CONCLUSIONS

In this large nationwide matched OHCA study, female patients had a better chance of survival with no significant difference in neurological outcome. We also noticed that female patients received delayed care with a shorter resuscitation effort compared to men; these complex issues warrant further specific investigation. Encouraging bystanders to act as quickly as possible and medical teams to care for female patients in the same way as male patients should increase survival rates.

Temporal Trends in the Incidence, Characteristics, and Outcomes of Hanging-Related Out-of-Hospital Cardiac Arrest

Aim: The aim of this study was to describe temporal trends in the incidence, characteristics, and outcomes of hanging-related out-of-hospital cardiac arrest (OHCA). Method: A retrospective study of all hanging-related OHCA in Victoria, Australia, between 2000 and 2017 was conducted. Trends in incidence, characteristics, and outcomes were assessed using linear regression and a non-parametric test for trend, as appropriate. Predictors of survival to hospital discharge were identified using multivariable logistic regression. Results: Between 2000 and 2017, emergency medical services (EMS)-attended 3,891 cases of hanging-related OHCA, of which 876 cases (23%) received an attempted resuscitation. The overall incidence rate of EMS-attended cases was 3.8 cases per 100,000 person-years increasing from 2.3 cases per 100,000 person-years in 2000 to 4.7 cases in 2017 (p for trend <0.001). Incidence rates increased approximately two-fold in young adults (18-44 years) and three-fold in middle aged adults (45-64 years). Despite improvement in the rate of bystander cardiopulmonary resuscitation (from 49% in 2000-2005 to 75% in 2012-2017), the survival to hospital discharge rate remained unchanged (3% overall). Among adult survivors with 12-month follow-up (n = 10), five patients responded to telephone interviews. Of those, three (60%) reported severe functional disability. Five patients responded to telephone interviews, of which 3 patients reported severe functional disability. An initial shockable rhythm (OR 23.17, 95% CI: 5.75, 93.36) or pulseless electrical activity (OR 13.14, 95% CI: 4.79, 36.03) were associated with survival. Conclusion: The incidence of hanging-related OHCA doubled over the 18 year period with no change to survival rates. New preventative strategies are needed to reduce the community burden of these events.

Coles and Woolworths have installed public access defibrillators in all their stores: It is time other Australian businesses followed their lead

We welcome the recent announcement by Coles and Woolworths that public access defibrillators (PADs) are now available in their stores, as early defibrillation with PADs is associated with significantly increased survival from out-of-hospital cardiac arrests (OHCAs). From 2008 to 2018 there were 120 OHCAs in Victorian supermarkets, overall 26.6% survived; however, when defibrillated by a PAD 66.6% survived. For all OHCA in Victoria, survival for defibrillation by a PAD was also higher at 55.5%, compared to 28.8% for paramedic defibrillation. Using this state-wide PAD survival rate, we estimate an additional 12 patients could have survived had PADs been available in all supermarkets. In Victoria last year there were 421 potentially viable OHCAs in public locations, of these 132 patients survived; however, had PADs been available an additional 101 patients could have survived. We therefore strongly encourage local businesses to install PADs, to safeguard the well-being of their employees, customers and local communities.

Trends in survival from out-of-hospital cardiac arrests defibrillated by paramedics, first responders and bystanders

BACKGROUND

Although survival from out-of-hospital cardiac arrest (OHCA) is increasing, little is known about the long-term trends in survival for patients defibrillated by first responders and bystanders.

METHODS

Between 2000 and 2017, we included adult non-traumatic OHCA with an initial shockable rhythm from the Victorian Ambulance Cardiac Arrest Registry. Adjusted logistic regression analyses were used to assess trends in survival to hospital discharge according to whether the patient was initially shocked by paramedics, first responders or bystanders.

RESULTS

Of the 10,451 initial shockable arrests, 796 (7.6%) and 526 (5.0%) were initially shocked by first responders and bystanders, respectively. Between 2000-02 and 2015-17, the proportion of cases initially shocked by first responders and bystanders increased from 3.8% to 8.2% and from 2.0% to 11.2%, respectively. Over the same period, survival to hospital discharge increased from 11.6% to 28.8% for cases initially shocked by paramedics, from 10.5% to 37.8% for cases initially shocked by first responders, and from 6.7% to 55.5% for cases initially shocked by bystanders (p trend <0.001 for all). In the adjusted analyses, patients initially shocked by first responders (AOR 1.40, 95% CI: 1.18, 1.67; p < 0.001) and bystanders (AOR 2.11, 95% CI: 1.72, 2.59; p < 0.001) were more likely to survive to hospital discharge than those initially shocked by paramedics. The odds of survival increased year-on-year by 8.1% for patients shocked by paramedics (p < 0.001), 6.1% for patients shocked by first responders (p = 0.004), and 11.8% for patients shocked by bystanders (p < 0.001).

CONCLUSION

OHCA patients initially defibrillated by bystanders yielded the largest improvements in survival over time.

Keeping Bystanders Active: Resuscitating Resuscitation Skills

Introduction: Sufficient CPR skills in the general population are essential to make them active bystanders and contribute to an effective chain of survival in cardiac arrest emergencies. However, having a large proportion of the population regularly retrained is practically infeasible.

Objective: The aim of this study was to assess and retrain cardiopulmonary resuscitation (CPR) skills of individuals who received (limited) CPR training several months to years prior.

Method: Ninety-nine German adults in a possession of a driver's license were asked to perform CPR on a Laerdal Resusci Anne^® QCPR manikin (Laerdal, Stavanger, Norway). After initial assessment, participants watched an instructional video and completed short, isolated compression, and ventilation practice with live feedback. CPR competency was assessed again after retraining and after a retention interval of 45 min.

Results: Our results indicate that only 2% of participants managed to reach the performance criteria set by the European Resuscitation Council Guidelines, with most failing to reach even the lowest levels of performance. This corroborates earlier observations that CPR skills have deteriorated almost completely after a long retention interval, calling into question “one-and-done” certification of this basic life-saving. However, we also demonstrated that performance strikingly increased after watching a 6-min instructional video and a short opportunity for isolated practice. This increase in performance was stable over 45 min with 96% of participants meeting performance levels specified in the Guidelines. Closer inspection of the isolated compression practice data suggests that performance was very high at the start of the practice already, indicating that short refresher videos might suffice to change bystanders that would not have initiated CPR due to lack of knowledge into active first responders.

Conclusion: We suggest that short refresher trainings could be an effective and affordable means of improving basic lifesaving skills to increase the effective contribution of bystanders during emergencies.

Factors determining level of hospital care and its association with outcome after resuscitation from pre-hospital pulseless electrical activity

Background

Patients resuscitated from out-of-hospital cardiac arrest (OHCA) with pulseless electrical activity (PEA) as initial cardiac rhythm are not always treated in intensive care units (ICUs): some are admitted to high dependency units with various level of care, others to ordinary wards. Aim of this study was to describe the factors determining level of hospital care after OHCA with PEA, post-resuscitation care and survival.

Methods

Adult OHCA patients with PEA (n = 221), who were resuscitated in southern Finland between 2010 and 2013 were included, provided patient survived to hospital admission. The patients were divided into four groups according to the level of hospital care provided: ordinary ward and Level 1–3 ICUs. Differences in patient characteristics, post-resuscitation care and survival were compared between the groups.

Results

Most patients (62.4%) were treated at Level 2 ICUs. Longer time to ROSC and advanced age decreased admission rate to Level 2 or 3 post-resuscitation care, whereas good pre-arrest CPC (1–2) increased the admission rate to Level 2/3 ICUs independently. Treatment with targeted temperature management (TTM) (4.1%) or early coronary angiography (3.2%) were very rare. Prognostic decisions were made earlier in the lower treatment intensity groups (p < 0.01). One-year survival rate was 24.0, 17.1% survived with good neurological outcome. Neurological outcome was better with more intensive care. After adjustment, level of care was not independent predictor for outcome: only return of spontaneous circulation (ROSC) time, cardiac arrest cause and pre-arrest performance affected independently to 1-year survival, age and ROSC for neurologic outcome.

Conclusions

PEA are usually admitted to Level 2 ICUs for post-resuscitation care in the capital area of Finland. Age, ROSC and pre-arrest CPC were independent predictors for level of post-resuscitation care. TTM and early CAG were rare and provided only for Level 3 ICU patients. Prognostication was earlier in lower level of care units. Good neurologic survival was more common with more intensive level of post-resuscitation care. After adjustment, level of care was not independent predictor for survival or neurologic outcome: only ROSC, cardiac arrest cause and pre-arrest performance predicted 1-year survival; age and ROSC neurologic outcome.

'Tell me exactly what's happened': When linguistic choices affect the efficiency of emergency calls for cardiac arrest

BACKGROUND

Clear and efficient communication between emergency caller and call-taker is crucial to timely ambulance dispatch. We aimed to explore the impact of linguistic variation in the delivery of the prompt "okay, tell me exactly what happened" on the way callers describe the emergency in the Medical Priority Dispatch System^®.

METHODS

We analysed 188 emergency calls for cases of paramedic-confirmed out-of-hospital cardiac arrest. We investigated the linguistic features of the prompt "okay, tell me exactly what happened" in relation to the format (report vs. narrative) of the caller's response. In addition, we compared calls with report vs. narrative responses in the length of response and time to dispatch.

RESULTS

Callers were more likely to respond with a report format when call-takers used the present perfect ("what's happened") rather than the simple past ("what happened") (Adjusted Odds Ratio [AOR] 4.07; 95% Confidence Interval [95%CI] 2.05-8.28, p<0.001). Reports were significantly shorter than narrative responses (9s vs. 18s, p<0.001), and were associated with less time to dispatch (50s vs. 58s, p=0.002).

CONCLUSION

These results suggest that linguistic variations in the way the scripted sentences of a protocol are delivered can have an impact on the efficiency with which call-takers process emergency calls. A better understanding of interactional dynamics between caller and call-taker may translate into improvements of dispatch performance.

Regions With Low Rates of Bystander Cardiopulmonary Resuscitation (CPR) Have Lower Rates of CPR Training in Victoria, Australia

Background

Bystander cardiopulmonary resuscitation (CPR) more than doubles the chance of surviving an out‐of‐hospital cardiac arrest. Recent data have shown considerable regional variation in bystander CPR rates across the Australian state of Victoria. This study aims to determine whether there is associated regional variation in rates of CPR training and willingness to perform CPR in these communities.

Methods and Results

We categorized each Victorian postcode as either a low or high bystander CPR region using data on adult, bystander‐witnessed, out‐of‐hospital cardiac arrests of presumed cardiac etiology (n=7175) from the Victorian Ambulance Cardiac Arrest Registry. We then surveyed adult Victorians (n=404) and compared CPR training data of the respondents from low and high bystander CPR regions. Of the 404 adults surveyed, 223 (55%) resided in regions with low bystander CPR. Compared with respondents from high bystander CPR regions, respondents residing in regions with low bystander CPR had lower rates of CPR training (62% versus 75%, P=0.009) and lower self‐ratings for their overall knowledge of CPR (76% versus 84%, P=0.04). There were no differences between the regions in their reasons for not having undergone CPR training or in their willingness to perform CPR. Rates of survival for bystander‐witnessed, out‐of‐hospital cardiac arrests were significantly lower in low bystander CPR regions (15.7% versus 17.0%, P<0.001).

Conclusions

This study found lower rates of CPR training and lower survival in regions with lower rates of bystander CPR in Victoria, Australia. Targeting these regions with CPR training programs may improve bystander CPR rates and out‐of‐hospital cardiac arrest outcomes.

Early predictors of poor outcome after out-of-hospital cardiac arrest

Background

Early identification of predictors for a poor long-term outcome in patients who survive the initial phase of out-of-hospital cardiac arrest (OHCA) may facilitate future clinical research, the process of care and information provided to relatives. The aim of this study was to determine the association between variables available from the patient’s history and status at intensive care admission with outcome in unconscious survivors of OHCA.

Methods

Using the cohort of the Target Temperature Management trial, we performed a post hoc analysis of 933 unconscious patients with OHCA of presumed cardiac cause who had a complete 6-month follow-up. Outcomes were survival and neurological function as defined by the Cerebral Performance Category (CPC) scale at 6 months after OHCA. After multiple imputations to compensate for missing data, backward stepwise multivariable logistic regression was applied to identify factors independently predictive of a poor outcome (CPC 3–5). On the basis of these factors, a risk score for poor outcome was constructed.

Results

We identified ten independent predictors of a poor outcome: older age, cardiac arrest occurring at home, initial rhythm other than ventricular fibrillation/tachycardia, longer duration of no flow, longer duration of low flow, administration of adrenaline, bilateral absence of corneal and pupillary reflexes, Glasgow Coma Scale motor response 1, lower pH and a partial pressure of carbon dioxide in arterial blood value lower than 4.5 kPa at hospital admission. A risk score based on the impact of each of these variables in the model yielded a median (range) AUC of 0.842 (0.840–0.845) and good calibration. Internal validation of the score using bootstrapping yielded a median (range) AUC corrected for optimism of 0.818 (0.816–0.821).

Conclusions

Among variables available at admission to intensive care, we identified ten independent predictors of a poor outcome at 6 months for initial survivors of OHCA. They reflected pre-hospital circumstances (six variables) and patient status on hospital admission (four variables). By using a simple and easy-to-use risk scoring system based on these variables, patients at high risk for a poor outcome after OHCA may be identified early.

Teaching school children basic life support improves teaching and basic life support skills of medical students: A randomised, controlled trial

BACKGROUND

The "kids save lives" joint-statement highlights the effectiveness of training all school children worldwide in cardiopulmonary resuscitation (CPR) to improve survival after cardiac arrest. The personnel requirement to implement this statement is high. Until now, no randomised controlled trial investigated if medical students benefit from their engagement in the BLS-education of school children regarding their later roles as physicians. The objective of the present study is to evaluate if medical students improve their teaching behaviour and CPR-skills by teaching school children in basic life support.

METHODS

The study is a randomised, single blind, controlled trial carried out with medical students during their final year. In total, 80 participants were allocated alternately to either the intervention or the control group. The intervention group participated in a CPR-instructor-course consisting of a 4h-preparatory seminar and a teaching-session in BLS for school children. The primary endpoints were effectiveness of teaching in an objective teaching examination and pass-rates in a simulated BLS-scenario.

RESULTS

The 28 students who completed the CPR-instructor-course had significantly higher scores for effective teaching in five of eight dimensions and passed the BLS-assessment significantly more often than the 25 students of the control group (Odds Ratio (OR): 10.0; 95%-CI: 1.9-54.0; p=0.007).

CONCLUSIONS

Active teaching of BLS improves teaching behaviour and resuscitation skills of students. Teaching school children in BLS may prepare medical students for their future role as a clinical teacher and support the implementation of the "kids save lives" statement on training all school children worldwide in BLS at the same time.

Prognostic factors associated with hospital survival in comatose survivors of cardiac arrest

AIM: To identify patient, cardiac arrest and management factors associated with hospital survival in comatose survivors of cardiac arrest.

METHODS: A retrospective, single centre study of comatose patients admitted to our intensive care unit (ICU) following cardiac arrest during the twenty year period between 1993 and 2012. This study was deemed by the Human Research Ethics Committee (HREC) of Monash Health to be a quality assurance exercise, and thus did not require submission to the Monash Health HREC (Research Project Application, No. 13290Q). The study population included all patients admitted to our ICU between 1993 and 2012, with a discharge diagnosis including “cardiac arrest”. Patients were excluded if they did not have a cardiac arrest prior to ICU admission (i.e., if their primary arrest was during their admission to ICU), or were not comatose on arrival to ICU. Our primary outcome measure was survival to hospital discharge. Secondary outcome measures were ICU and hospital length of stay (LOS), and factors associated with survival to hospital discharge.

RESULTS: Five hundred and eighty-two comatose patients were admitted to our ICU following cardiac arrest, with 35% surviving to hospital discharge. The median ICU and hospital LOS was 3 and 5 d respectively. There was no survival difference between in-hospital and out-of-hospital cardiac arrests. Males made up 62% of our cardiac arrest population, were more likely to have a shockable rhythm (56% vs 37%, P < 0.001), and were more likely to survive to hospital discharge (40% vs 28%, P = 0.006). On univariate analysis, therapeutic hypothermia, regardless of method used (e.g., rapid infusion of ice cold fluids, topical ice, “Arctic Sun”, passive rewarming, “Bair Hugger”) and location initiated (e.g., pre-hospital, emergency department, intensive care) was associated with increased survival. There was however no difference in survival associated with target temperature, time at target temperature, location of initial cooling, method of initiating cooling, method of maintaining cooling or method of rewarming. Patients that survived were more likely to have a shockable rhythm (P < 0.001), shorter time to return of spontaneous circulation (P < 0.001), receive therapeutic hypothermia (P = 0.03), be of male gender (P = 0.006) and have a lower APACHE II score (P < 0.001). After multivariate analysis, only a shockable initial rhythm (OR = 6.4, 95%CI: 3.95-10.4; P < 0.01) and a shorter time to return of spontaneous circulation (OR = 0.95, 95%CI: 0.93-0.97; P < 0.01) was found to be independently associated with survival to hospital discharge.

CONCLUSION: In comatose survivors of cardiac arrest, shockable rhythm and shorter time to return of spontaneous circulation were independently associated with increased survival to hospital discharge.

Public access defibrillation—results from the Victorian Ambulance Cardiac Arrest Registry

AIM

To assess the impact of automated external defibrillator (AED) use by bystanders in Victoria, Australia on survival of adults suffering an out-of-hospital cardiac arrest (OHCA) in a public place compared to those first defibrillated by emergency medical services (EMS).

METHODS

We analysed data from the Victorian Ambulance Cardiac Arrest Registry for individuals aged >15 years who were defibrillated in a public place between 1 July 2002 and 30 June 2013, excluding events due to trauma or witnessed by EMS.

RESULTS

Of 2270 OHCA cases who arrested in a public place, 2117 (93.4%) were first defibrillated by EMS and 153 (6.7%) were first defibrillated by a bystander using a public AED. Use of public AEDs increased almost 11-fold between 2002/2003 and 2012/2013, from 1.7% to 18.5%, respectively (p < 0.001). First defibrillation occurred sooner in bystander defibrillation (5.2 versus 10.0 min, p < 0.001). Unadjusted survival to hospital discharge for bystander defibrillated patients was significantly higher than for those first defibrillated by EMS (45% versus 31%, p < 0.05). Multivariable logistic regression analysis showed that first defibrillation by a bystander using an AED was associated with a 62% increase in the odds of survival to hospital discharge (adjusted odds ratio 1.62, 95% CI: 1.12–2.34, p = 0.010) compared to first defibrillation by EMS.

CONCLUSION

Survival to hospital discharge is improved in patients first defibrillated using a public AED prior to EMS arrival in Victoria, Australia. Encouragingly, bystander AED use in Victoria has increased over time. More widespread availability of AEDs may further improve outcomes of OHCA in public places.

Prevalence of emergency medical service utilisation in patients with out-of-hospital cardiac arrest in Thailand

BACKGROUND

Most patients with out-of-hospital cardiac arrest (OHCA) have grave outcomes. The efficacy of emergency medical services (EMS) may affect outcomes. However, no data exists in Thailand.

OBJECTIVES

To ascertain the prevalence of EMS utilisation in patients with OHCA transferred to Siriraj Hospital and also to elucidate the rates of return of spontaneous circulation (ROSC), hospital admission and survival to hospital discharge.

METHODS

This prospective cohort study was conducted in patients with OHCA at a university hospital in Bangkok, Thailand from May 2011 to February 2013. The data was gathered by interviewing bystanders. Data about the mode of transportation, reasons for EMS usage, response time, ROSC and 30-day mortality were collected. Patients with rigour mortis or livor mortis were excluded. The factors affecting ROSC and survival rate were determined by univariate analysis.

RESULTS

One hundred and fifty-two patients were included. The prevalence of EMS usage was 14.5% (95% CI 9.3 to 21.0). The most common cause of non-usage of EMS was not knowing or forgetting an EMS number (49.2%). The proportion of bystanders having known an EMS number and using EMS was 34%. The ROSC and 30-day survival rates were 53.3% and 10.5%, respectively. Non-cardiac causes and witnessed arrests were associated with ROSC (p<0.05).

CONCLUSIONS

The prevalence of EMS utilisation in OHCA at Siriraj Hospital was very low. This may affect the outcomes of patients with OHCA. Improving the EMS system by publicity to increase public awareness and providing life-support education nationwide may improve outcomes of patients with OHCA in Thailand.

Forest Fire Smoke Exposures and Out-of-Hospital Cardiac Arrests in Melbourne, Australia: A Case-Crossover Study

BACKGROUND

Millions of people can potentially be exposed to smoke from forest fires, making this an important public health problem in many countries.

OBJECTIVE

In this study we aimed to measure the association between out-of-hospital cardiac arrest (OHCA) and forest fire smoke exposures in a large city during a severe forest fire season, and estimate the number of excess OHCAs due to the fire smoke.

METHODS

We investigated the association between particulate matter (PM) and other air pollutants and OHCA using a case-crossover study of adults (≥ 35 years of age) in Melbourne, Australia. Conditional logistic regression models were used to derive estimates of the percent change in the rate of OHCA associated with an interquartile range (IQR) increase in exposure. From July 2006 through June 2007, OHCA data were collected from the Victorian Ambulance Cardiac Arrest Registry. Hourly air pollution concentrations and meteorological data were obtained from a central monitoring site.

RESULTS

There were 2,046 OHCAs with presumed cardiac etiology during our study period. Among men during the fire season, greater increases in OHCA were observed with IQR increases in the 48-hr lagged PM with diameter ≤ 2.5 μm (PM2.5) (8.05%; 95% CI: 2.30, 14.13%; IQR = 6.1 μg/m(3)) or ≤ 10 μm (PM10) (11.1%; 95% CI: 1.55, 21.48%; IQR = 13.7 μg/m(3)) and carbon monoxide (35.7%; 95% CI: 8.98, 68.92%; IQR = 0.3 ppm). There was no significant association between the rate of OHCA and air pollutants among women. One hundred seventy-four "fire-hours" (i.e., hours in which Melbourne's air quality was affected by forest fire smoke) were identified during 12 days of the 2006/2007 fire season, and 23.9 (95% CI: 3.1, 40.2) excess OHCAs were estimated to occur due to elevations in PM2.5 during these fire-hours.

CONCLUSIONS

This study found an association between exposure to forest fire smoke and an increase in the rate of OHCA. These findings have implications for public health messages to raise community awareness and for planning of emergency services during forest fire seasons.

Using a cardiac arrest registry to measure the quality of emergency medical service care: decade of findings from the Victorian Ambulance Cardiac Arrest Registry

BACKGROUND

Although the value of clinical registries has been well recognized in developed countries, their use for measuring the quality of emergency medical service care remains relatively unknown. We report the methodology and findings of a statewide emergency medical service surveillance initiative, which is used to measure the quality of systems of care for patients with out-of-hospital cardiac arrest.

METHODS AND RESULTS

Between July 1, 2002, and June 30, 2012, data for adult out-of-hospital cardiac arrest cases of presumed cardiac cause occurring in the Australian Southeastern state of Victoria were extracted from the Victorian Ambulance Cardiac Arrest Registry. Regional and temporal trends in bystander cardiopulmonary resuscitation, event survival, and survival to hospital discharge were analyzed using logistic regression and multilevel modeling. A total of 32,097 out-of-hospital cardiac arrest cases were identified, of whom 14,083 (43.9%) received treatment by the emergency medical service. The risk-adjusted odds of receiving bystander cardiopulmonary resuscitation (odds ratio [OR], 2.96; 95% confidence interval, 2.62-3.33), event survival (OR, 1.55; 95% confidence interval, 1.30-1.85), and survival to hospital discharge (OR, 2.81; 95% confidence interval, 2.07-3.82) were significantly improved by 2011 to 2012 compared with baseline. Significant variation in rates of bystander cardiopulmonary resuscitation and survival were observed across regions, with arrests in rural regions less likely to survive to hospital discharge. The median OR for interhospital variability in survival to hospital discharge outcome was 70% (median OR, 1.70).

CONCLUSIONS

Between 2002 and 2012, there have been significant improvements in bystander cardiopulmonary resuscitation and survival outcome for out-of-hospital cardiac arrest patients in Victoria, Australia. However, regional survival disparities and interhospital variability in outcomes pose significant challenges for future improvements in care.

Impact of Fine Particulate Matter (PM2.5) Exposure During Wildfires on Cardiovascular Health Outcomes

Background

Epidemiological studies investigating the role of fine particulate matter (PM_2.5; aerodynamic diameter <2.5 μm) in triggering acute coronary events, including out-of-hospital cardiac arrests and ischemic heart disease (IHD), during wildfires have been inconclusive.

Methods and Results

We examined the associations of out-of-hospital cardiac arrests, IHD, acute myocardial infarction, and angina (hospital admissions and emergency department attendance) with PM_2.5 concentrations during the 2006–2007 wildfires in Victoria, Australia, using a time-stratified case-crossover study design. Health data were obtained from comprehensive health-based administrative registries for the study period (December 2006 to January 2007). Modeled and validated air exposure data from wildfire smoke emissions (daily average PM_2.5, temperature, relative humidity) were also estimated for this period. There were 457 out-of-hospital cardiac arrests, 2106 emergency department visits, and 3274 hospital admissions for IHD. After adjusting for temperature and relative humidity, an increase in interquartile range of 9.04 μg/m³ in PM_2.5 over 2 days moving average (lag 0-1) was associated with a 6.98% (95% CI 1.03% to 13.29%) increase in risk of out-of-hospital cardiac arrests, with strong association shown by men (9.05%,95%CI 1.63% to 17.02%) and by older adults (aged ≥65 years) (7.25%, 95% CI 0.24% to 14.75%). Increase in risk was (2.07%, 95% CI 0.09% to 4.09%) for IHD-related emergency department attendance and (1.86%, 95% CI: 0.35% to 3.4%) for IHD-related hospital admissions at lag 2 days, with strong associations shown by women (3.21%, 95% CI 0.81% to 5.67%) and by older adults (2.41%, 95% CI 0.82% to 5.67%).

Conclusion

PM_2.5 exposure was associated with increased risk of out-of-hospital cardiac arrests and IHD during the 2006–2007 wildfires in Victoria. This evidence indicates that PM_2.5 may act as a triggering factor for acute coronary events during wildfire episodes.

The significance of pre-arrest factors in out-of-hospital cardiac arrests witnessed by emergency medical services: a report from the Victorian Ambulance Cardiac Arrest Registry

BACKGROUND

The significance of pre-arrest factors in out-of-hospital cardiac arrests (OHCA) witnessed by emergency medical services (EMS) is not well established. The purpose of this study was to assess the association between prodromal symptoms and pre-arrest clinical observations on the arresting rhythm and survival in EMS witnessed OHCA.

METHODS

Between 1st January 2003 and 31st December 2011, 1056 adult EMS witnessed arrests of a presumed cardiac aetiology were identified from the Victorian Ambulance Cardiac Arrest Registry. Pre-arrest prodromal features and clinical characteristics were extracted from the patient care record. Backward elimination logistic regression was used to identify pre-arrest factors associated with an initial shockable rhythm and survival to hospital discharge.

RESULTS

The median age was 73.0 years, 690 (65.3%) were male, and the rhythm of arrest was shockable in 465 (44.0%) cases. The most commonly reported prodromal symptoms prior to arrest were chest pain (48.8%), dyspnoea (41.8%) and altered consciousness (37.8%). An unrecordable systolic blood pressure was observed in 34.4%, a respiratory rate <13 or >24min(-1) was present in 43.1%, and 45.5% had a Glasgow coma score <15. In the multivariable analysis, the following pre-arrest factors were significantly associated with survival: age, public location, aged care facility, chest pain, arm or shoulder pain, dyspnoea, dizziness, vomiting, ventricular tachycardia, pulse rate, systolic blood pressure, respiratory rate, Glasgow coma score, aspirin and inotrope administration.

CONCLUSION

Pre-arrest factors are strongly associated with the arresting rhythm and survival following EMS witnessed OHCA. Potential opportunities to improve outcomes exist by way of early recognition and management of patients at risk of OHCA.

Quality of life and functional outcomes 12 months after out-of-hospital cardiac arrest

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) is a significant global health problem. There has been considerable investment in improving the emergency medical response to OHCA, with associated improvements in survival. However, concern remains that survivors have a poor quality of life. This study describes the quality of life of OHCA survivors at 1-year postarrest in Victoria, Australia.

METHODS AND RESULTS

Adult OHCA patients who arrested between 2010 and 2012 were identified from the Victorian Ambulance Cardiac Arrest Registry. Paramedics attended 15 113 OHCA patients of which 46.3% received an attempted resuscitation. Nine hundred and twenty-seven (13.2%) survived to hospital discharge of which 76 (8.2%) died within 12 months. Interviews were conducted with 697 (80.7%) patients or proxies, who were followed-up via telephone interview, including the Glasgow Outcome Scale-Extended, the 12-item short form health survey, and the EuroQol. The majority (55.6%) of respondents had a good recovery via the Glasgow Outcome Scale-Extended≥7 (41.1% if patients who died postdischarge were included and nonrespondents were assumed to have poor recovery). The mean EuroQol index score for respondents was 0.82 (standard deviation, 0.19), which compared favorably with an adjusted population norm of 0.81 (standard deviation, 0.34). The mean 12-item short form Mental Component Summary score for patients was 53.0 (standard deviation, 10.2), whereas the mean Physical Component Summary score was 46.1 (standard deviation, 11.2).

CONCLUSIONS

This is the largest published study assessing the quality of life of OHCA survivors. It provides good evidence that many survivors have an acceptable quality of life 12 months postarrest, particularly in comparison with population norms.

Improved outcome in Sweden after out-of-hospital cardiac arrest and possible association with improvements in every link in the chain of survival

AIMS

To describe out-of-hospital cardiac arrest (OHCA) in Sweden from a long-term perspective in terms of changes in outcome and circumstances at resuscitation.

METHODS AND RESULTS

All cases of OHCA (n = 59,926) reported to the Swedish Cardiac Arrest Register from 1992 to 2011 were included. The number of cases reported (n/100,000 person-years) increased from 27 (1992) to 52 (2011). Crew-witnessed cases, cardiopulmonary resuscitation prior to the arrival of the emergency medical service (EMS), and EMS response time increased (P < 0.0001). There was a decrease in the delay from collapse to calling for the EMS in all patients and from collapse to defibrillation among patients found in ventricular fibrillation (P < 0.0001). The proportion of patients found in ventricular fibrillation decreased from 35 to 25% (P < 0.0001). Thirty-day survival increased from 4.8 (1992) to 10.7% (2011) (P < 0.0001), particularly among patients found in a shockable rhythm and patients with return of spontaneous circulation (ROSC) at hospital admission. Among patients hospitalized with ROSC in 2008-2011, 41% underwent therapeutic hypothermia and 28% underwent percutaneous coronary intervention. Among 30-day survivors in 2008-2011, 94% had a cerebral performance category score of 1 or 2 at discharge from hospital and the results were even better if patients were found in a shockable rhythm.

CONCLUSION

From a long-term perspective, 30-day survival after OHCA in Sweden more than doubled. The increase in survival was most marked among patients found in a shockable rhythm and those hospitalized with ROSC. There were improvements in all four links in the chain of survival, which might explain the improved outcome.

The association between systolic blood pressure on arrival at hospital and outcome in adults surviving from out-of-hospital cardiac arrests of presumed cardiac aetiology

BACKGROUND

The optimal blood pressure target following successful resuscitation from out-of-hospital cardiac arrest (OHCA) is uncertain. This study aimed to explore the association between level of systolic blood pressure (SBP) on arrival at hospital and survival to hospital discharge.

METHODS

We analysed eligible OHCAs occurring between January 2003 and December 2011 from the Victorian Ambulance Cardiac Arrest Register (VACAR). Inclusion criteria were: adults (≥18 years), presumed cardiac aetiology, not paramedic witnessed, and ROSC at hospital arrival. Multivariate logistic regression models were performed by initial rhythm (shockable/non-shockable) to examine the relationship between SBP at hospital arrival in 10 mmHg increments and survival to hospital discharge. Models were adjusted for known predictors of survival, including duration of arrest.

RESULTS

Of 3620 eligible cases, 14% were hypotensive (SBP<90 mmHg) on hospital arrival (10% shockable and 19% non-shockable). For patients in shockable rhythms, discharge survival was maximal at 120-129 mmHg (54%), and in the adjusted model (≥120 mmHg as reference) SBP decrements below 90 mmHg were associated with lower survival: 80-89 mmHg AOR=0.49 (95% CI: 0.24-0.95); <80 mmHg AOR=0.24 (95% CI: 0.10-0.61); unrecordable AOR=0.10 (95% CI: 0.04-0.30). In patients found in non-shockable rhythms, SBP was not significant associated with discharge survival (AOR=1.01, 95% CI: 0.89-1.15).

CONCLUSIONS

In an EMS system using intravenous adrenaline and fluids to maintain post-resuscitation SBP at 120 mmHg, hypotension on hospital arrival was relatively uncommon. However, in presumed cardiac OHCA patients with an initial shockable rhythm, SBPs below 90 mmHg was associated with significant lower odds of survival to hospital discharge. This level of hypotension may indicate patients who require more aggressive post-resuscitation blood pressure management.

An automated CPR device compared with standard chest compressions for out-of-hospital resuscitation

Background

Effective cardiopulmonary resuscitation and increased coronary perfusion pressures have been linked to improved survival from cardiac arrest. This study aimed to compare the rates of survival between conventional cardiopulmonary resuscitation (C-CPR) and automated CPR (A-CPR) using AutoPulse™ in adults following out-of-hospital cardiac arrest (OHCA).

Methods

This was a retrospective study using a matched case–control design across three regional study sites in Victoria, Australia. Each case was matched to at least two (maximum four) controls using age, gender, response time, presenting cardiac rhythm and bystander CPR, and analysed using conditional fixed-effects logistic regression.

Results

During the period 1 October 2006 to 30 April 2010 there were 66 OHCA cases using A-CPR. These were matched to 220 cases of OHCA involving the administration of C-CPR only (controls). Survival to hospital was achieved in 26% (17/66) of cases receiving A-CPR compared with 20% (43/220) of controls receiving C-CPR and the propensity score adjusted odds ratio [AOR (95% CI)] was 1.69 (0.79, 3.63). Results were similar using only bystander witnessed OHCA cases with presumed cardiac aetiology. Survival to hospital was achieved for 29% (14/48) of cases receiving A-CPR compared with 18% (21/116) of those receiving C-CPR [AOR = 1.80 (0.78, 4.11)].

Conclusions

The use of A-CPR resulted in a higher rate of survival to hospital compared with C-CPR, yet a tendency for a lower rate of survival to hospital discharge, however these associations did not reach statistical significance. Further research is warranted which is prospective in nature, involves randomisation and larger number of cases to investigate potential sub-group benefits of A-CPR including survival to hospital discharge.

Design of the RINSE trial: the rapid infusion of cold normal saline by paramedics during CPR

Background

The International Liaison Committee on Resuscitation (ILCOR) now recommends therapeutic hypothermia (TH) (33°C for 12-24 hours) as soon as possible for patients who remain comatose after resuscitation from shockable rhythm in out-of-hospital cardiac arrest and that it be considered for non shockable rhythms. The optimal timing of TH is still uncertain. Laboratory data have suggested that there is significantly decreased neurological injury if cooling is initiated during CPR. In addition, peri-arrest cooling may increase the rate of successful defibrillation. This study aims to determine whether paramedic cooling during CPR improves outcome compared standard treatment in patients who are being resuscitated from out-of-hospital cardiac arrest.

Methods/Design

This paper describes the methodology for a definitive multi-centre, randomised, controlled trial of paramedic cooling during CPR compared with standard treatment. Paramedic cooling during CPR will be achieved using a rapid infusion of large volume (20-40 mL/kg to a maximum of 2 litres) ice-cold (4°C) normal saline.

The primary outcome measure is survival at hospital discharge. Secondary outcome measures are rates of return of spontaneous circulation, rate of survival to hospital admission, temperature on arrival at hospital, and 12 month quality of life of survivors.

Discussion

This trial will test the effect of the administration of ice cold saline during CPR on survival outcomes. If this simple treatment is found to improve outcomes, it will have generalisability to prehospital services globally.

Trial Registration

ClinicalTrials.gov: NCT01172678