ARTICLE IN PRESS Resuscitation xxx (2011) xxx xxx

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Resuscitation

j o u r n a l h o m e p a g e :w w w . e l s e v i e r . c o m / l o c a t e / r e s u s c i t a t i o n

Clinical paper

Quality management in resuscitation – Towards a European Cardiac Arrest

Registry (EuReCa)

夽

J.T. Gräsner

_{, J. Herlitz}

_{, R.W. Koster}

_{, F. Rosell-Ortiz}

_{, L. Stamatakis}

_{, L. Bossaert}

c_{afd. Cardiologie, Kamer F3-239, Academisch Medisch Centrum, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands} d_{Empresa Pública de Emergencias (Public Utility for Health Emergencies), Sanitarias, Almería, Spain}

e_{Department of Emergency Medicine CHU Tivoli, ULB, La Louvière, Belgium}

f_{University of Antwerp, Faculty of Medicine Universitetisplein 1, B2610 Antwerp, Belgium}

a r t i c l e i n f o

Article history:

Received 1 December 2010

Received in revised form 20 February 2011 Accepted 23 February 2011 Available online xxx Keywords: Resuscitation Cardiac arrest Registry Register Quality management ERC

a b s t r a c t

Background:Knowledge about the epidemiology of cardiac arrest in Europe is inadequate.

Aim:To describe the first attempt to build up a Common European Registry of out-of-hospital cardiac arrest, called EuReCa.

Methods:After approaching key persons in participating countries of the European Resuscitation Council, five countries or areas within countries (Belgium, Germany, Andalusia, North Holland, Sweden) agreed to participate. A standardized questionnaire including 28 items, that identified various aspects of resus-citation, was developed to explore the nature of the regional/national registries. This comprises inclusion criteria, data sources, and core data, as well as technical details of the structure of the databases. Results:The participating registers represent a population of 35 million inhabitants in Europe. During 2008, 12,446 cardiac arrests were recorded. The structure as well as the level of complexity varied markedly between the 5 regional/national registries. The incidence of attempted resuscitation ranged between registers from 17 to 53 per 100,000 inhabitants each year whilst the number of patients admit-ted to hospital alive ranged from 5 to 18 per 100,000 inhabitants each year. Bystander CPR varied 3-fold from 20% to 60%.

Conclusion:Five countries agreed to participate in an attempt to build up a common European Registry for out-of-hospital cardiac arrest. These regional/national registries show a marked difference in terms of structure and complexity. A marked variation was found between countries in the number of reported resuscitation attempts, the number of patients brought to hospital alive, and the proportion that received bystander CPR. At present, we are unable to explain the reason for the variability but our first findings could be a ‘wake-up-call’ for building up a high quality registry that could provide answers to this and other key questions in relation to the management of out-of-hospital cardiac arrest.

© 2011 Elsevier Ireland Ltd. All rights reserved.

1. Introduction

In 2008, the European Resuscitation Council (ERC) set up a working group with the objective of creating a uniform European Registry of Cardiac Arrests (EuReCa), based on the existing expe-riences from member countries. It must encompass variations in EMS structure, organisation, and interventions, whilst including the involvement of diverse participants including bystanders, ambu-lance personnel, and critical care specialists. Reports will reflect the

夽_{A Spanish translated version of the summary of this article appears as Appendix}

in the final online version atdoi:10.1016/j.resuscitation.2011.02.047.

∗_{Corresponding author. Tel.: +49 431 597 2971; fax: +49 431 597 3002.}

E-mail address:graesner@anaesthesie.uni-kiel.de(J.T. Gräsner).

use of international guidelines that define current resuscitation and provide recommendations for optimal emergency care.1–7_{In 1991,} the Utstein Style for uniform reporting on cardiac arrest and resus-citation was developed to permit the collection of comparable data. It has been used for numerous registries, studies, and analyses of out-of-hospital cardiac arrest.8–14_{However, an up to date system} to provide a European overview and monitoring of cardiac arrest and resuscitation is not yet available.

1.1. International resuscitation registries, registries of cardiac arrest, and quality management systems

Large registries of out-of-hospital and in-hospital cardiac arrest already exist. In North America, at least three are in place. The Resuscitation Outcomes Consortium (ROC) Epistry Cardiac Arrest 0300-9572/$ – see front matter© 2011 Elsevier Ireland Ltd. All rights reserved.

gency Medical Services (EMS) in eight US and three Canadian regions.15–17_{The American Heart Association’s National Registry of} CardioPulmonary Resuscitation (NRCPR) is a multicentre registry of in-hospital cardiac arrests.18,19_{The third one is the Cardiac Arrest} Registry to Enhance Survival (CARES) which was created to provide communities with a means to identify cases of out-of-hospital car-diac arrest, measure how well emergency medical services (EMS) perform key elements of emergency cardiac care, and determine outcomes through hospital discharge.20

These three registries in selected high-quality sites benefit from a standardized EMS system and a uniform legislation that allows valid comparison between sites.

1.2. EMS and registries in Europe

A distinction may be made between the term “register” (refer-ring to the regional/national database of individual records) and the term “registry” (referring to the anonimised collection of regional/national registers for global analysis). In the interest of simplicity, the term “registry” is used to describe both.

The ERC defines Europe as the European continent according to the definition by the Council of Europe, with 47 countries and 823 million inhabitants.21

The situation in Europe is different from that in North Amer-ica: individual countries have EMS systems of varying types and legislation, making a unified registry a more complex issue.22_EMS is organised either as a single or as a two-tiered system following national customs and laws for BLS and ALS. ALS may be performed by paramedics, specialised nurses, or physicians. The registries that had previously been set up in Europe are therefore local, covering services of a similar nature.

1.3. Variations in outcome: real or artefactual?

Systematic reviews of literature emphasised that results differ substantially between and within countries and regions.23–25_{In the} past 2 decades, several investigators have emphasised how differ-ences in EMS organisation may influence comparative studies.22–25 They will also be affected by non-uniform definitions. However, the observation that outcome may vary by a factor of 3 requires an analysis of the individual steps in emergency care.26

1.4. Aims of EuReCa

The primary purpose of the ERC is to improve the quality and outcome of resuscitation applied to cardiac arrest victims in Europe.

EuReCa can facilitate that goal because it will permit:

•Identification of differences in interpretation of definitions so that they may be more uniformly applied;

•Valid comparison of process and outcome between regions and countries;

•Identification of weak local, regional, or national links in the chain of survival and assistance in improvement;

•Evaluation of potential improvements in procedures;

•Evaluation of changes in guidelines;

•Generation of convincing evidence to encourage financial support for evaluation and improvement of organisation and process;

•Creation of a network for national and international scientific cooperation in the field of cardiopulmonary resuscitation.

2.1. Study group

Participants from five existing European registries agreed to be included after a call to all member councils of the ERC: Andalusia (Spain), Belgium, Germany, North-Holland (the Netherlands) and Sweden.

2.2. Inclusion criteria

Existing and active registries collecting data on resuscitation attempts for out-of-hospital cardiac arrest, regardless of age. 2.3. Data collection

In order to describe the participating registries, EuReCa devel-oped a standardized questionnaire (Supplement 1) including 28 items, to explore details of the region, the dissemination and scope of the respective registry, the data sources used, the inclusion cri-teria, the participants, the core data, and time intervals. In addition, technical details of the structure of the databases were collected. The questionnaires were completed by the national or regional coordinators of the respective registries and were refined by inter-views during site visits.

Core data and time intervals were defined and recorded in accor-dance with to the Utstein-Style protocol.12,13

2.4. Site visits

In addition to submitting their questionnaires, the five partic-ipating registration centres were visited and their coordinators interviewed by the same investigator (JTG). The questionnaire was used as a framework for the interview.

3. Results

3.1. Participating registries and population represented

Overall, the participating registries represent a population of 34.9 million inhabitants. Two registries (Belgium and Andalu-sia) record all EMS interventions or resuscitation attempts at the national or regional level and thus provide a complete coverage. Two registries (Sweden and North-Holland) cover fully a defined part/region of the country. German resuscitation registry records data on a national level, but participating centres represent only 9% of the total population.

3.2. Description of the registries 3.2.1. Belgium

This registry is organised by the Ministry of Health; it records resuscitation attempts by the EMS system for all the 11 million inhabitants of Belgium. Since participation is mandatory, documen-tation should be complete. Case record forms are completed by the EMS team; data are then transferred to a central database. Informa-tion from the admitting hospitals is also collected centrally with a delay of up to 18 months.

3.2.2. Germany

The German Resuscitation Registry represents 4.5 million citi-zens (total population of Germany 85 million) and collects data on out- and in-hospital resuscitation attempts throughout the coun-try. Participation is voluntary. Currently, 150 emergency centres record data on resuscitation attempts. These centres are an inte-gral part of public EMS systems; they are staffed by physicians from

Data sources.

Data sources Belgium Germany Andalusia North-Holland Sweden

Dispatch centre Yes Yes Yes Yes Yes

Ambulance defib No Sometimes No Yes Yes

AED No Sometimes Yes Yes Yes

Run sheet EMS Yes Yes Yes Yes Yes

Emergency department No Sometimes Yes Yes Yes

Hospital departments No Sometimes Yes Yes Yes

Discharge information No Sometimes Yes Yes Yes

Vital status at discharge No Sometimes Yes Yes Yes

Vital status after 3 months No Sometimes Yes Yes No

Vital status after 6 months No Sometimes Yes Yes No

Vital status after 12 months No Sometimes Yes Yes No

several medical disciplines (predominantly anaesthesia, surgery, internal medicine) with additional training in emergency medicine. The inclusion rate was reported to be 60–100%. The registry is organised and financed by the national Society of Anaesthesiology (Deutsche Gesellschaft für Anästhesiologie und Intensivmedizin DGAI).27,28,38

3.2.3. Andalusia

This registry is a quality management system in a defined part of the country with 8 million inhabitants (total population of Spain 46.9 million). All EMS responses for out-of-hospital cardiac arrest are recorded. The registry is organised by the public health organi-sation. Financing forms part of the general reimbursement of EMS costs. Data for the registry are collected online electronically by the dispatching centre and linked appropriately. Information from the admitting hospitals is also collected centrally and recorded in the database. Quality control is under the supervision of a dedicated working group.

3.2.4. North Holland

This regional cardiac arrest registry is part of a scientific project to study resuscitation care and outcome in a defined part of the country with 2.4 million inhabitants (total population of the Netherlands 16.5 million). The inclusion rate is >90%. The registry is organised from an academic centre and is financed by industrial sponsors and scientific organisations. Data from suspected cardiac arrest are telephoned by the paramedic to the coordinating cen-tre that records the response details, emergency protocols, and follow-up information to hospital discharge, as well as data stored electronically from the AED/defibrillator including ECG rhythms, timestamps, number of shocks, etc. There is a rigid quality control.29 3.2.5. Sweden

This national resuscitation registry covers the population of Sweden (9 million). Participation is voluntary. Based on the expe-rience over more than 20 years, the register recorded 70–100% of all resuscitation attempts throughout the country in 2009.

Organ-isation is in the hands of the National Resuscitation Council. Data are recorded online. In addition, the coordination centre receives information from the admitting hospital—including discharge sta-tus enabling completion of those variables needed for analysing outcome data.14,30,31

3.3. Initial results

The five selected registries recorded 12,446 attempted resusci-tations in one year. The incidence varied among the registries from 17 to 53/100,000 inhabitants/year; the numbers achieving ROSC from 5 to 18/100,000 inhabitants/year; and the rate of admission to hospital also from 5 to 18/100,000 inhabitants/year (Table 3). The number with arrests of presumed cardiac cause varied from 13 to 44/100,000 inhabitants/year with ROSC in this group ranging from 3 to 14/100,000 inhabitants/year.

All five registries have defined the inclusion criteria required for opening a data set. None has age limits. Belgium and Andalu-sia record all emergency cases attended by the EMS. The cause of the arrest is recorded in all registries. Andalusia and North-Holland require a reason for “do not attempt resuscitation”. Andalusia, North-Holland and Sweden use set criteria for termination of resus-citation (TOR).

3.4. Data collection and data sources (Table 1)

Data relating to resuscitation attempts are available from obtaining timestamps (dispatch centre), treatment information (run sheets, reports from emergency departments and hospi-tals, discharge information), real-time records of clinical variables (AED/defibrillator), or information about outcome at discharge at three, six or 12 months after resuscitation.

‘Admission to hospital’ is recorded in all registries, whereas only Andalusia, North-Holland and Sweden record hospital discharge data. Andalusia and North-Holland also report survival to one year. The registry in Belgium has access to information from run sheets only but a link to outcome data is planned.

Table 2

EMS process and time points.

EMS process Belgium Germany Andalusia North-Holland Sweden

Witnessed collapse recorded? No Yes Yes Yes Yes

Bystander CPR recorded ? No Yes Yes Yes Yes

Therapeutic hypothermia recorded No Yes Yes Yes Yes

Time points

Moment of alert Yes Yes Yes Yes Yes

Moment of dispatch Yes Yes Yes Yes Yes

Vehicle arrives at site Yes Yes Yes Yes Yes

Arrival at the patient’s side No Yes Sometimes Yes Yes

Defibrilator connection No No Sometimes Yes Yes

First shock No Yes Sometimes Yes Yes

Incidence and results.

Belgium Germany Andalusia North-Holland Sweden

Reported year 2009 2008 2008 2008 2008

Total population in the reported Region (Millions) 10.7 4.5 5.6 2.4 9

OHCA for which EMS is called 10,533 1566

Incidence of EMS called for OHCA/100,000 98 65

OHCA considered for resuscitation 5671 1048 1116

Incidence of OHCA considered for resuscitation/100,000 53 19 47

Resuscitation started 5671 1882 955 1116 2822

Incidence of started resuscitation/100,000 53.0 41.8 17.1 46.5 31.4

Cardiac causes 4682 1515 737 1006 1711

Incidence of started resuscitation in cardiac causes/100,000 44 34 13 42 19

non cardiac causes 989 659 214 110 1111

Incidence of started resuscitation in non cardiac causes/100,000 9 14.6 3.8 4.6 12.3

Any ROSC (all causes) 829 261 732

Incidence any ROSC (all causes)/100,000 18.4 4.7 8.1

ROSC CC 642 187

Incidence of ROSC CC/100,000 14.3 3.3

ROSC nCC 170 73

Incidence of ROSC nCC/100,000 3.8 1.30

Admitted to hospital (all causes) 1875 669 255 444 690

Incidence of admitted to hospital (all causes)/100,000 17.5 14.9 4.6 18.5 7.7

Admitted to hospital CC 1525 507 162 376 435

Incidence admitted to hospital CC/100,000 14.3 11.3 2.9 15.7 4.8

Admitted to hospital nCC 350 162 69 68 238

Incidence admitted to hospital nCC/100,000 3.3 3.6 1.2 2.8 2.6

Discharged from hospital (all causes) 235 242

Incidence from discharged from hospital (all causes)/100,000 9.9 2.6

Discharged from hospital CC 221 180

In addition to the raw number of cases, results are also expressed per 100,000 inhabitants/year for the purpose of comparison. *No data = no information about this aspect.

Core data of the process and time points are shown inTable 2. Core data on incidence and outcome after OHCA is shown in Table 3.

4. Discussion

The five registries selected for this study represent nearly 35 million European citizens out of the 830 million. They describe different areas of care in varying detail, ranging from limited information about the resuscitation process to registries includ-ing comprehensive physiological parameters and access to further databases—residents registers, registers of death, health insurance registers, and hospital information.

This initial survey reveals the potential for a Europe-wide com-parison, but it also identifies the limitations. Several reasons could explain the reluctance of other countries to cooperate at present with EuReCa. We assume that many have not yet started to build up a cardiac arrest register. Some countries have started but may feel that their register is not representative enough for submission to a European survey. Some colleagues may feel uncertain that it is appropriate to send their data outside their own country. Some countries might withhold their data for ‘protective’ reasons. Finally, some colleagues might feel that they are unable to find time for this type of collaboration.

All European resuscitation organisations and councils should assume responsibility to report the massive burden of cardiac arrest, the resuscitation process, and outcome within their areas. This is possible only with registration of key variables and using a uniform style of reporting that can permit identification and con-sequences of differences in the systems of care within Europe. 4.1. Cardiac arrest registry vs. resuscitation registry

The information submitted to date has come from dedicated resuscitation registries (Germany and Sweden), cardiac arrest reg-istries (North-Holland) and components of general EMS regreg-istries (Belgium and Andalusia). Thus, a direct comparison of data is

difficult, since dedicated resuscitation registries may not pro-vide information on cardiac arrests for which resuscitation is not attempted, thus potentially concealing an unintended selection bias. The number of cases per 100,000 inhabitants/year was calcu-lated as a surrogate to support the validity of direct comparisons; this is not completely reliable because in most systems some patients are also treated by other medical facilities that may not liaise with the EMS. A complete record of resuscitations that are managed by the EMS should be available with reliable methods to avoid inclusion bias. If resuscitation or cardiac arrest data are collected on an EMS documentation system, a complete record is guaranteed, as occurs in Belgium and Andalusia.

The EuReCa registry will initially focus on resuscitation attempts by the EMS, provided it can be related to the size of the popula-tion of the registry. The data basis for a European registry should, however, not be established on the lowest common denomina-tor. On the other hand a comprehensive system with a wealth of detailed information (North-Holland) must not be taken as the benchmark for the minimum standard. Publications reporting the resuscitation process and the Utstein definitions clearly describe the minimum number of variables necessary12,13,32–36_{that includes} the initial rhythm, whether the event was witnessed or not, 1-month survival (ideally with neurological status), and time from call to EMS intervention and to the first defibrillator shock; the group of patients with witnessed collapse and initial VF provide a comparator group.30,32

Not all of the five participating registries could provide full data because legal constraints limit the sharing of information between pre-hospital and in-hospital care systems especially with regard to discharge statistics. Therefore, the integrated ID-sensitive infor-mation of pre-hospital, in-hospital, and discharge data should be collected by the local registry in an anonymous form for inclusion in the EuReCa database.

For describing processes, certain additional time points in the chain of care are of the utmost importance.

The 1991 Utstein style version concentrated on comprehensive epidemiological aspects, whereas later updates put forward

pro-show, exactly as the European ones, deviations with regard to the recommendations on the complexity of the Utstein protocol. For epidemiological questions other data are needed than for detailed descriptions of medical care. Where required, a re-definition of the Utstein protocol might be useful, taking into account these different questions. At this stage, however, the Utstein protocols already per-mit flexible use. Maybe that interpretations of Utstein definitions are based on uncertainties concerning handling the protocols. Cur-rently, due to its complexity Utstein may cover nearly any problem, however, on the other hand the complexity may demand too much of interested centres. Selecting data fields according to the focus of own analyses may help, but if fields from the Utstein portfolio are selected for the own database they have to be consistent with the specified Utstein definitions. New definitions of one’s own, devi-ating from Utstein, would hamper or even make impossible the comparability with other registries.

The time of arrival at the patient side, important for assessing the no-flow time, cannot be recorded reliably. In case of bystander CPR the no-flow-time would also be difficult to describe due to time information that is difficult to obtain.37_{The time of the first} defibrillator shock, however, is a core variable. When an AED is used by a lay rescuer, the interval between the alert and the arrival of the EMS is also relevant.

4.2. Treatment procedures and description of process

The resuscitation record provides a common basis for analysing causes of OHCA, ECG rhythms, bystander interventions, and treat-ment measures including post-resuscitation managetreat-ment. Four of the five registries provide the required data sets. For subsequent investigations, however, more detailed analyses of data definitions are needed. The fact that the rate of bystander CPR differs among the participating registries by more than a factor of three (15% in Andalusia compared with 60% in North-Holland and Sweden) may be artefactual because of underreporting or reflect real differ-ences in education and implementation. Artefactual discrepancies must be excluded through the use of unambiguous definitions and complete reporting.

4.3. The future of EuReCa

EuReCa may develop into a central tool for quality management in resuscitation and may eventually include countries and regions that up to now have not set up registries of their own. Thus, apart from its role as a European registry, EuReCa could serve as a tool for a national registry for new participants.

All registries included in EuReCa must be checked in detail and if necessary modified in order to ensure comparability of data.

One of the greatest challenges is the application of unambiguous definitions. This can be met by close co-operation of those respon-sible for the national registries within the EuReCa consortium, to ensure that throughout Europe the data can be truly comparable. This necessitates both careful quality control with the use of uni-form definitions and valid data sources in all contributing countries and groups.

Experience has shown that combining pre-hospital and in-hospital data may be problematical. Local structures have to be taken into account and legal requirements observed. Since legal regulations are not uniform throughout Europe, EuReCa will include only anonymous data approved by national or regional registries in accordance with respective national data protec-tion regulaprotec-tions. The collecprotec-tion of long-term survival data also requires local or regional solutions to achieve linkage between care providers.

Five countries or areas within countries accepted an invitation to contribute to an attempt to build up a common European Reg-istry for out of hospital cardiac arrest. These registries show marked differences in terms of structure and complexity. Considerable vari-ation was found between countries in the number of registered CPR attempts, number of patients brought to hospital alive, and the proportion of bystander attempts. At present, the reasons for this variability cannot be explained adequately.

Conflict of interest statement

None of the authors have declared a conflict of interest.

Appendix A. Supplementary data

Supplementary data associated with this article can be found, in the online version, atdoi:10.1016/j.resuscitation.2011.02.047.

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