S. Bernard

Epidemiology of paediatric out-of-hospital cardiac arrest in Melbourne, Australia

BACKGROUNDnPrevious studies of paediatric cardiac arrest have reported a low survival rate but there is limited data from Australia. We sought to determine the characteristics and outcomes of paediatric out-of-hospital cardiac arrest in Melbourne, Australia.nnnMETHODSnBetween October 1999 and June 2007, all cases of out-of-hospital cardiac arrest attended by emergency medical services in Melbourne, Australia were entered into a database (the Victorian Ambulance Cardiac Arrest Registry). Data on patients aged less than 16 years in cardiac arrest on arrival of ambulance paramedics was analysed.nnnRESULTSnThere were 209 children in cardiac arrest on arrival of paramedics during the study period. Of these, resuscitation was not attempted in 16 children due to signs of definite death. Of the 193 children who had attempted resuscitation, 143 (74%) had an initial cardiac rhythm of asystole, 36 (18%) were in pulseless electrical activity and 14 (7%) were in ventricular fibrillation. There were 49 patients (25%) with return of spontaneous circulation at arrival to hospital of whom 14 (7%) survived to hospital discharge. Of 138 patients without return of a circulation, 120 were transported to hospital with continuing resuscitation and one survived (0.9%). Survival was higher in patients with an initial cardiac rhythm of ventricular fibrillation (5/14; 35%) compared with other rhythms (10/179; 4%), OR 9.38, 95% CI 2.64-33.2.nnnCONCLUSIONSnOverall, 7.7% of paediatric patients with out-of-hospital cardiac arrest survive to leave hospital. Increased survival was seen if the initial cardiac rhythm was ventricular fibrillation. Survival was very rare (<1%) unless there was return of spontaneous circulation prior to hospital arrival.

Out-of-hospital cardiac arrests in young adults in Melbourne, Australia-Adding coronial data to a cardiac arrest registry

AIMnWe aim to describe the coronial findings of young adults where the out-of-hospital cardiac arrest (OHCA) aetiology was presumed cardiac.nnnMETHODSnPresumed cardiac aetiology OHCAs occurring in young adults aged 16-39 years were identified using the Victorian Ambulance Cardiac Arrest Registry (VACAR) and available coronial findings reviewed.nnnRESULTSnWe identified 841 young adult OHCAs where the Utstein aetiology was presumed cardiac. Of these 740 died and 572 (77%) OHCAs were matched to coroners findings. On review of the coroners cause of death, 230 (40.2%) had a confirmed cardiac aetiology, 221 (38.6%) were proven non-cardiac, 97 (17%) were inconclusive and 24 (4.2%) cases remained open. Confirmed cardiac causes of OHCA were ischemic heart disease (n=126, 55%), cardiomegaly (n=26, 11.3%), cardiomyopathy (n=25, 11%), congenital heart disease (n=15, 6.5%), cardiac tamponade due to dissecting thoracic aorta aneurysm (n=10, 4.3%), myocarditis (n=8, 3.5%), arrhythmia (n=7, 3%), others (n=13, 5.7%). Non-cardiac causes of OHCA were epilepsy/sudden unexplained death in epilepsy (SUDEP) (n=56, 25%), pulmonary embolism (n=29, 13%), subarachnoid haemorrhage (n=17, 7.7%), other intracranial bleed (n=7, 3.2%), pneumonia (n=17, 7.7%), DKA (n=16, 7.2%), other complications of diabetes mellitus (n=8, 3.6%), complications of obesity (n=9, 4%), haemorrhage (n=12, 5.4%), sepsis (n=8, 3.6%), peritonitis (n=6, 2.7%), aspiration (n=6, 2.7%), renal failure (n=5, 2.3%), asthma (n=5, 2.3%), complications of anorexia (n=3) and alcohol abuse (n=2), thyrotoxicosis (n=2), meningitis (n=1) and others (n=12). Compared with coroners diagnosed non-cardiac OHCAs, confirmed cardiac were more likely to be witnessed (41% vs 23%, p≤0.01), receive bystander CPR (35% vs 20%, p≤0.001), have a shockable rhythm (27% vs 6.3%, p<0.001) and have EMS attempted resuscitation (62% vs 44%, p<0.001).nnnDISCUSSIONnLinking OHCA registries with coronial databases for aetiology of the arrest will improve the quality of the data and should be considered by all OHCA registries, particularly for young adult OHCA.

Paediatric traumatic out-of-hospital cardiac arrests in Melbourne, Australia

INTRODUCTIONnMany 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.nnnMETHODSnThe 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.nnnRESULTSnBetween 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%).nnnCONCLUSIONSnTraumatic 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.

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

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

Paediatric hanging associated out of hospital cardiac arrest in Melbourne, Australia: characteristics and outcomes

Introduction Hanging is a rare but devastating cause of out of hospital cardiac arrest (OHCA). The characteristics and outcomes of hanging associated OHCA in the paediatric age group are described. Methods The Victorian Ambulance Cardiac Arrest Registry was searched for patients aged less than 18u2005years where the precipitant cause of OHCA was hanging. Results were cross checked with the coronial database. Results During the years 2000–2009, there were 680 paediatric cardiac arrests of which 53 (7.8%) were precipitated by hanging with an incidence of 4.4 per million paediatric patients (<18u2005years) per year. Median age was 16 (IQR 14–17)u2005years and 58.5% were males. Five were unintentional hangings; median age 3 (IQR 2–4)u2005years. The youngest deliberate hanging associated OHCA was aged 10u2005years. Most hangings occurred in a house (85%) and bystander cardiopulmonary resuscitation (CPR) was performed in 30%. Asystole was the most common initial cardiac arrest rhythm seen in 50 cases (94%) while three patients had pulseless electrical activity. The emergency medical services (EMS) attempted resuscitation in 18 patients (34%), inserting an endotracheal tube in 13 patients. The majority (n=41) were not transported; seven patients were transported with return of spontaneous circulation (ROSC) and five patients were transported with ongoing CPR. Victims who had bystander CPR were more likely to have EMS attempted resuscitation (p<0.001). Only patients who had received bystander CPR achieved ROSC (p<0.001). Three patients survived to hospital discharge; two survivors suffered severe neurological injury (Cerebral Performance Category Scale 3–4). Conclusion Non-intentional hanging is rare but deliberate hanging with suicidal intent represents a significant proportion of OHCAs in patients under 18u2005years of age. A focus on prevention is key, as outcomes are poor, with survivors likely to suffer a severe neurological insult.

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

BACKGROUNDnSuccess rates from cardiopulmonary resuscitation (CPR) are often quantified by Utstein-style outcome reports in populations who receive an attempted resuscitation. In some cases, evidence of futility is ascertained after a partial resuscitation attempt has been administered, and these cases reduce the overall effectiveness of CPR. We examine the impact of partial resuscitation attempts on the reported outcomes of out-of-hospital cardiac arrest (OHCA) in Victoria, Australia.nnnMETHODSnBetween 2002 and 2012, 34,849 adult OHCA cases of presumed cardiac aetiology were included from the Victorian Ambulance Cardiac Arrest Registry. Resuscitation attempts lasting ≤10min in cases which died on scene were defined as a partial resuscitation. We used logistic regression to identify factors associated with a partial resuscitation attempt in the emergency medical service (EMS) treated population. Survival outcomes with and without partial resuscitations were compared across included years.nnnRESULTSnThe proportion of partial resuscitations in the overall EMS treated population increased significantly from 8.6% in 2002 to 18.8% in 2012 (p for trend<0.001), and were largely supported by documented evidence of irreversible death. Partial resuscitations were independently associated with older age, female gender, initial non-shockable rhythm, prolonged downtime, and lower skill level of EMS personnel. Selectively excluding partial resuscitations increased event survival by 7.6% (95% CI 4.1-11.2%), and survival to hospital discharge increased by 3.1% (95% CI 0.5-5.7%) in 2012 (p<0.001 for both).nnnCONCLUSIONnIn our EMS system, evidence of futility was often identified after the commencement of a partial resuscitation attempt. Excluding these events from OHCA outcome reports may better reflect the overall effectiveness of CPR.

Early ECPR for out-of-hospital cardiac arrest: Best practice in 2018

Extracorporeal CPR is a second line treatment for refractory cardiac arrest, as written in the latest International Guidelines. Optimal timing, patient selection, location and method of implementation vary across the world. The objective here is to present an international consensus on the pillars of an ECPR program. The major aspect the group agrees on in that ECPR should be implemented within 60 minutes of collapse. With this in mind, the program should be built according to local resources knowing that the optimal team will require pre-established specific roles with personnel dedicated to resuscitation and others to ECPR.

48 Trends in the incidence and outcome of paediatric out-of-hospital cardiac arrest in victoria, australia

Aim System-based improvements to the chain of survival have yielded significant increases in survival from out-of-hospital cardiac arrest (OHCA) in adults. Comparatively little is known about the long-term trends in incidence and survival following paediatric OHCA. Method Between 2000 and 2016, we included paediatrics aged ≤16 years who suffered a non-traumatic OHCA in the state of Victoria, Australia. Trends in incidence and unadjusted outcomes were assessed using linear regression. Adjusted trends in event survival and survival to hospital discharge were assessed using multivariable logistic regression. Results Of the 1301 paediatric OHCA attended by emergency medical services (EMS), 948 (72.9%) received an attempted resuscitation. The overall incidence of EMS-attended OHCA was 6.7 cases per 1u200900u2009000 person-years, with no significant change over time. Although median EMS response times increased over time, the proportion of cases with OHCA identified in the call and receiving bystander cardiopulmonary resuscitation (CPR) also increased. Unadjusted event survival rose from 23.3% in 2000 to 33.3% in 2016 (p trend=0.007). Over the same period, survival to hospital discharge rose from 9.4% to 17.7% (p trend=0.04). After multivariable adjustment, the odds of event survival and survival to hospital discharge increased independently of arrest factors, by 7% (OR 1.07, 95%u2009CI: 1.03, 1.12; p=0.001) and 8% (OR 1.08, 95%u2009CI: 1.01, 1.15; p=0.02) respectively. Bystander CPR and OHCA identification in the call were not associated with survival. Conclusion In our region, survival following paediatric OHCA increased significantly over a 17u2009year period. However, the factors contributing to this improvement require further investigation. Conflict of interest None Funding ZN is funded by a National Health and Medical Research Council (NHMRC) Early Career Fellowship (#1146809).

6 Characteristics of thunderstorm asthma EMS attendances in victoria, australia

Aim Thunderstorm Asthma (TA) occurs when a dangerous mix of pollen and severe weather trigger acute respiratory distress symptoms in people with allergic rhinitis and asthma. We sought to describe the characteristics of patients attended by emergency medical services (EMS) during the largest global epidemic of TA which occurred in Melbourne on 21/11/2016. Methods A retrospective observational study of electronic EMS patient care records was conducted for all cases occurring during TA, between 1800hrs on 21/11/2016 and 2359u2009hours on 22/11/2016 (30 hours). Results were compared with a standard comparator period defined as the seven days prior to the event (14/11/2016 to 20/11/2016). Results EMS responded to 3631 cases during the TA event, compared with an average of 2419 cases per 30u2009hours during the comparator period. During TA, the final paramedic diagnosis was acute respiratory distress in 28.3% of patients (Asthma=18.0%, Shortness of Breath=10.3%), compared with 3.6% of patients during the comparator period (Asthma=0.6%, Shortness of Breath=3.0%, p<0.001). Whilst there was an absolute increase in the number of time-critical cases, the proportion of acute respiratory illness patients considered time-critical after initial paramedic assessment remained stable between the two periods (42.0% vs. 43.5%, p=0.6). However, a 50% increase in the rate of out-of-hospital cardiac arrest was observed during TA. In the cohort of Asthma patients, 74.9% reported a history of asthma during TA compared with 91.1% during the comparator period (p=0.006). The most common paramedic intervention for patients with acute respiratory distress was administration of salbutamol (72.5%) while 8.0% of patients received adrenaline. Conclusion The TA event in Melbourne was associated with a significant increase in EMS attendances to patients with acute respiratory illnesses and cardiac arrest. Conflict of interest None declared. Funding None declared.

35 Manual versus semi-automatic rhythm analysis and defibrillation for out-of-hospital cardiac arrest

Aim Although manual and semi-automatic external defibrillation (SAED) are commonly used in the management of cardiac arrest, the optimal strategy is not known. We hypothesised that SAED would reduce the time to first shock and increase survival compared to a manual strategy. Methods Between 2005 and 2015, we included adult out-of-hospital cardiac arrests (OHCA) of presumed cardiac aetiology. On October 2012, a treatment protocol utilising SAED was introduced following years of manual defibrillation by paramedics. The effect of SAED implementation on patient outcomes was assessed using adjusted interrupted time series models. Results Of the 14u2009776 cases, 10u2009224 (69.2%) and 4552 (30.8%) occurred during the manual and SAED protocols, respectively. After adjustment for arrest confounders and temporal trend, the odds of delivering the first shock within 2u2009min of arrival increased under the SAED protocol (adjusted odds ratio [AOR] 1.72, 95%u2009CI: 1.32, 2.26; p<0.001). Despite this, the SAED protocol was associated with a reduction in return of spontaneous circulation (AOR 0.81, 95%u2009CI: 0.68, 0.96; p=0.01), event survival (AOR 0.74, 95%u2009CI: 0.62, 0.88; p=0.001) and survival to hospital discharge (AOR 0.71, 95%u2009CI: 0.55, 0.92; p=0.009) when compared with the manual protocol. Although SAED reduced the time to first shock, there was no improvement in the rate of successful first shock cardioversion (AOR 0.73, 95%u2009CI: 0.51, 1.06; p=0.10). Conclusion Although SAED improved the time to first shock, this did not translate into higher rates of successful cardioversion or survival for OHCA patients. Advanced life support providers should be trained in a manual defibrillation protocol. Conflict of interest None declared. Funding None declared.