Public access defibrillation-

Results from the Victorian Ambulance Cardiac Arrest Registry (VACAR)

M Lijovic1,2, S Bernard1,2, Z Nehme1,2, T Walker1 and K Smith1,2,3, on behalf of the Victorian Ambulance Cardiac Arrest Registry Steering Committee

1Ambulance Victoria, 2Monash University, 3University of WA

This presentation will address:

• Burden of out-of-hospital cardiac arrest (OHCA)

• Emergency medical services, public access defibrillation (PAD) programs and automated external defibrillator (AED) locations in Victoria, Australia

• Victorian Ambulance Cardiac Arrest Registry (VACAR)

• OHCA is a significant public health problem

In Victoria, Australia, the annual incidence of adult OHCA attended by ambulance is 120.8 events per 100,000 population (Victorian Ambulance Cardiac Arrest Registry Annual Report 2013/14. 2014, Ambulance Victoria).

• For every minute delay in response time, survival decreases by 9%

(95% CI, 4-14%) Cardiac arrests of presumed cardiac aetiology, presenting in VF/VT and

where resuscitation is attempted by emergency medical services (EMS) (Fridman et al. Resuscitation 2007)

• Improved survival rates are possible, in spite of increasing response times, if bystanders perform CPR and defibrillate using an automated external defibrillator (AED)

Burden of out-of-hospital cardiac arrest

Public access defibrillation programs

• The AHA, ERC and Australian and New Zealand Resuscitation Councils advocate defibrillation through PAD programs (Weisfeldt et al. Circulation, 1995; Australian and New Zealand Resuscitation Councils, 2011; Nolan et al. Resuscitation, 2010) AEDs in the community, particularly in locations with high incidence of

arrests, to facilitate rapid defibrillation by laypersons prior to EMS arrival • Public AED programs have effectively been used in communities

Survival to discharge: 31 - 69% (Hallstrom et al. NEJM, 2004; Kitamura et al. NEJM, 2010; Eckstein et al, Resuscitation, 2012; Nielsen et al. Resuscitation, 2013)

AED application before EMS arrival increased likelihood of survival to discharge (AOR 1.75; 95% CI, 1.23-2.50) (Weisfeldt et al. J Am Coll Cardiol 2010)

Bystander CPR+defib (30 survivors/128), bystander CPR (15 survivors/107) CPR+defib = More survivors (RR 2.0; 95% CI, 1.07-3.77) (Hallstrom et al)

Limited Australian data

• To date, one small study assessing impact of public AEDs in limited sites in Victoria showed its potential to improve patient survival (Wassertheil et al. 2000) St John first aid volunteers using AEDs at two public locations Of 28 patients, 24 (86%) survived ‘at scene’ & 20 (71%) discharged home

• No population-based studies assessing impact of PAD in Victoria

AIM • Retrospective analysis of adults suffering an OHCA using a

population-based registry in Victoria

• Assess the impact of first defibrillation by a bystander with a public AED compared to first defibrillation by EMS on survival-related outcomes

STUDY SETTING

• Ambulance Victoria is the major provider of emergency ambulance services in Victoria

5.7 million (population); 227,416 km2 (area) Follow Australian Resus Council guidelines

• Victorian emergency medical services (EMS):

AV (Advanced Life Support & MICA paramedics) Fire-fighters co-respond metro Melbourne & sections of outer Melbourne Community Emergency Response Teams (CERTs) in rural areas

Emergency medical services in Victoria

• In 2002, the Victorian State Government announced it would fund a PAD program with Metropolitan Ambulance Service & Rural Ambulance Victoria (now Ambulance Victoria, AV)

AV provides annual training at each site, ongoing support/ education,

clinical debriefing and peer support following significant events & ‘skills refresher’ follow-up visits every 2 months

AV PAD program in Victoria

AV PAD sites

Metropolitan region Rural region

AV PAD Program No. AEDs AV PAD Program No. AEDsMelbourne Airport 34 Otway Fly 1

Wyndham Leisure Centre 1 Queenscliff Ferry 2Ashburton Recreational Centre 1 Avalon Airport 3

Croydon Leisure Centre 2 Sovereign Hill 3Federation Square 1 Mildura Airport 1

Kew Recreational Centre 1 Phillip IslandMetro Trains (4 city stations) 9 >> Penguin Parade 2

NGV Aust- Fed Square 1 >> Seal Rock 1NGV Inter- St Kilda Rd 2 >> Koala Park 1

Ringwood Aquatic Centre -- >> Churchill Island 1Shrine 3 TOTAL Rural 15

Werribee Zoo 2Healesville Sanctuary 2

Melbourne Zoo 2Southern Cross Station 5

Chadstone Shopping Centre 10TOTAL Metro 76 TOTAL Metro and Rural 91

• Since mid 2002, AV has allocated and maintained 91 AEDs in 25 areas of high public attendance and/or site of arrests around Victoria

• AV also maintains a record of AED locations within the community “Opt in” AED registry The location of 1500 AEDs in the community have been registered with

AV by the owner(s) of these AEDs via the website: http://www.registermyaed.com.au/

• AED locations are entered into the computer aided dispatch system so that ‘000’ callers can be alerted to a defibrillator located nearby Locations include businesses, sports clubs, community groups, other

public venues (e.g. casino)

• At some public sites, volunteer first-aid agencies have AEDs for use

by trained staff

Other AED locations in Victoria

VACAR

• Data on all OHCA patients attended by ambulance in Victoria Data collection since 1999 (> 75,000 cases)

Information such as whether a patient is defibrillated by a member of the public with an AED is included in the VACAR

VACAR

AV Patient Care

Records

Fire, CERT PCRs

Fire, CERT, AV PAD

ECG

AV ECG

Computer Aided Dispatch

response data

Event Register

QOL survey

Hospital/ coroners

data

Audit Death Registry

RESULTS

Study population

Definition of bystander defibrillation

• ‘First defibrillated by a bystander with a public AED’: Bystander using a public AED at a site maintained by the local EMS or maintained by another organisation or St John first aid volunteers using an AED at a public event

• Of 153 patients first defibrillated by a bystander with a public AED, 25 cases AV-maintained PAD site 26 cases Public event (by a first-aid volunteer) 102 cases Site not maintained by AV

Common sites where public AED used

• Most common locations of arrest where individual first defibrillated with a public AED’: International airport in the capital city Melbourne (n=18, 12%) 2 sporting venues in Melbourne with large public events attended by

St John first aid volunteers (n=18, 12%) Casino in the capital city (n=4, 2.5%)

Remaining cases defibrillated at other sites around state (n=113, 74%)

Public sites where individuals were defibrillated

Location

Street / car park / public road / motor vehicle 1167 ( 55% ) 33 ( 22% )

Recreation/ sporting complex 386 ( 18% ) 76 ( 50% )

Workplace 296 ( 14% ) 13 ( 8% )

Airport 0 ( 0% ) 18 ( 12% )

All other public places 268 ( 14% ) 13 ( 8% )

First shocked by EMS

(n=2,117)

First shocked by bystander with

public AED (n=153)

Frequency (%) Frequency (%)

Population characteristics

P valueAge, years (median, IQR) 0.246 Unknown, n (%)Male gender, n (%) 1860 ( 88% ) 138 ( 88% ) 0.390Cardiac precipitating event, n (%) 2058 ( 97% ) 148 ( 97% ) 0.729Bystander witnessed, n (%) 1765 ( 84% ) 134 ( 88% ) 0.214 Unknown, n (%)Bystander CPR, n (%) 1571 ( 74% ) 146 ( 95% ) <0.001EMS Response time, mins (median, IQR) 0.017 Unknown, n (%)Time to first shock, mins (median, IQR) <0.001 Unknown, n (%)Survival to hospital, n (%) 1059 ( 51% ) 99 ( 66% ) <0.001 Unknown, n (%)Survival to hospital discharge, n (%) 637 ( 31% ) 66 ( 45% ) 0.001 Unknown, n (%)Percentages exclude unknown values.^ Median time to first shock for patients first defibrillated with a public AED includes 41 cases (27%) where time to first shock was estimated from event chronology and applying an average time difference between being at the patient/ commencing CPR and first defibrillation. Excluding these 41 shock time estimates gives rise to a median (IQR) time to first shock of 5.4 (4.0-8.0) which is not significantly different from the estimate shown in the table.

63 (53, 74)Frequency (%) Frequency (%)

63 (52, 71)

60 (3% ) 13 (8% )

26 (1% ) 2 (1% )

73 (3% ) 6 (4% )

First shocked by EMS

(n=2,117)

First shocked by bystander with

public AED (n=153)

7.3 (5.8, 10.0) 8.0 (6.1, 10.9)

10.0 (8.0, 13.0) 5.2 (4.0, 8.0)^

4 (0.2%) 0 (0%)

10 (0.5% ) 0 (0% )

38 (2% ) 6 (4% )

PAD outcomes in Victoria vs other PAD studies

Non-traumatic cases shocked with public AED, nSurvival to hospital discharge, n (%)

Bystander witnessed & cardiac cause, nSurvival to hospital discharge, n (%)

Bystander witnessed, nSurvival to hospital discharge, n (%)

Presumed cardiac origin, nSurvival to hospital discharge, n (%)

Cases defibrillated at airport, nSurvival to hospital discharge, n (%)

Eckstein et al. Resuscitation 2012;83(11):1411-2. Valenzuela et al. N Engl J Med 2000;343(17):1206-9.Weisfeldt et al. J Am Coll Cardiol 2010;55(16):1713-20. Nielsen et al. Resuscitation 2013;84(4):430-4.Kitamura et al. N Engl J Med 2010;362(11):994-1004. Caffrey et al. N Engl J Med 2002;347(16):1242-7.

188 of 17 (47% ) 11 of 18 (61%)

Caffrey et al.

56 of 124 (45%)

148 Nielsen et al. 27 of 55 (49%)

63 of 142 (44%) 20 of 29 (69%)30-day neurol-intact surv

If shock after >3 mins,

Weisfeldt et al.64 of 170 (38%)Kitamura et al.

146 of 462 (32%)

First shocked by bystander with

public AED (n=153)

Comparator PAD study

58 of 128 (45%) 53 of 90 (59%)

66 of 153 (45%) 27 of 29 (69%)

30-day neurol-intact surv

130

"

Valenzuela et al.134

153Frequency (%) Frequency (%)

Eckstein et al.

Logistic regression- Survival to discharge

Predictor variable Odds ratio 95% CI P value

Age 0.98 0.97 - 0.98 <0.001

EMS response time 0.87 0.85 - 0.90 <0.001

Bystander CPR 2.52 1.96 - 3.24 <0.001

Public witnessed 1.32 1.01 - 1.72 0.045

Excluded from model:Male gender, cardiac precipitating event n.sTime to first shock

First defibrillation by bystander with public AED 1.62 1.12 - 2.34 0.010

First defibrillation with a public AED associated with improved odds for survival to hospital discharge, compared to first defibrillation by EMS 62% increase in chance of survival to hospital discharge

[ Adjusted odds ratio 1.75 (95% CI, 1.23-2.50) Weisfeldt et al. ]

Limitations • Retrospective study design

• Unable to quantify the number of arrests where a public AED may

have been at the location but was not used

• For cases defibrillated by a bystander using a public AED, initial rhythm was verified if AED readings were made available to VACAR Presence of VF/VT was assumed on the basis that the public AED

provided defibrillation

• Completeness of AV AED registry relies upon voluntary registration of installed AEDs by members of the community via website Only one-fifth of AEDs were in the AV-AED Registry

Conclusions & Recommendations

Conclusions

• Survival to hospital discharge is improved in patients first defibrillated using a public AED prior to the arrival of EMS in Victoria, Australia

Recommendations • Increasing PAD programs in additional sites

• Increasing awareness of AV AED registry, so that more AEDs are

registered with the EMS, may improve AED accessibility Lijovic et al. Public access defibrillation — results from the Victorian Ambulance Cardiac Arrest Registry. Resuscitation. 2014 Dec;85(12):1739-44.

Acknowledgements

• VACAR team: Karen Smith Resmi Nair Vanessa Barnes Marian Lodder Davina Vaughan Kerri Anastasopoulos

• AV paramedics, EMR and CERT teams

Dr Marijana Lijovic marijana.lijovic@ambulance.vic.gov.au

VACAR Senior Research Fellow Research and Evaluation, Ambulance Victoria

Phone +61 3 9896 6090