Clinical paperImproving outcome after out-of-hospital cardiac arrest by strengthening weak links of the local Chain of Survival; quality of advanced life support and post-resuscitation care☆
Introduction
Guidelines for cardiopulmonary resuscitation are developed in order to improve survival after cardiac arrest. Despite evolving evidence-based guidelines for cardiopulmonary resuscitation (CPR),1, 2 survival rates after out-of-hospital cardiac arrest (OHCA) has not improved much.3, 4 The Chain of Survival concept of early access, early CPR, early defibrillation and good post-resuscitation care is the documented and recommended guide for improving outcome after OHCA.1, 2, 5 Documenting Utstein data for OHCA is a useful tool for evaluating and critically assessing the local Chain of Survival in an emergency medical service (EMS), identifying areas in need of improvement in order to increase survival after OHCA.6
In Oslo, Norway, survival to hospital discharge for OHCA of cardiac aetiology has been below 10% for the last 30 years.7, 8, 9 In the time period from 1996 to 1998 the ALS providers in the Oslo EMS were trained according to 1992 guidelines,10 resulting in poor ALS quality with long periods without vital organ perfusion and few shocks resulting in return of spontaneous circulation (ROSC).8 In 2001 the 2000 international guidelines11, 12 were implemented with a modification consisting of increased focus on chest compression quality including 3 min periods of CPR before and between defibrillations, based on findings from local ALS studies.8, 13 The main aim of these changes was to optimize vital organ perfusion by minimizing interruptions in chest compression and more reasonable timing of defibrillations,14 defined as improving the third link in our local Chain of Survival. A standardized post-resuscitation treatment protocol including therapeutic hypothermia and percutaneous coronary intervention (PCI) was implemented in 2003 to strengthen the last link.15
Through implementation of new and modified guidelines and evolving scientific evidence, our local Chain of Survival was thereby changed throughout this 9-year period, with special focus on the last two links. The first period (1996–1998) had poor ALS quality and post-resuscitation care, the second period (2001–2003) had good ALS quality but poor post-resuscitation care, and the third period (2004–2005) had both good ALS quality and post-resuscitation care. In the present study we wanted to evaluate if these temporal changes strengthened our local Chain of Survival and impacted on outcome after OHCA.
Section snippets
Description of Oslo
The city of Oslo covers 454 km2 and has 548,617 inhabitants (January 1st 2007) with 51% female population and 4.4% of the population over 80 years. Oslo has had a continuous population growth the last 20 years, mainly due to migration leading to a larger proportion of young adults 20–39 and lower proportion of children and adults >40 years compared to the rest of the country.16
Description of EMS and in-hospital treatment
The city of Oslo has a one-tiered community run EMS system. All acute care ambulances are manned with paramedics. On
Results
During the three study periods, altogether 1320 patients received ALS for OHCA. The Utstein style results from the three study periods are reported in Table 1.
Discussion
Despite an increase in negative prognostic factors such as more unwitnessed non-VF arrests and increased response intervals, outcome was significantly improved during our 9-year study period. The greatest improvements in survival were seen in bystander witnessed VF/VT arrests of cardiac origin, which may be considered the most homogenous and therefore easiest comparable group of patients within the cardiac arrest population.6 Continuous focus on the importance of a well functioning Chain of
Conclusion
The increasing proportion of survivors with favourable neurological outcome, both overall and for all sub-groups, indicates that the strengthening of the last two links in our local Chain of Survival has lead to significantly improved outcome for patients with out-of-hospital cardiac arrest.
Contributions
Lund-Kordahl and Olasveengen have full access to all generated data and take full responsibility for the integrity of the data and the accuracy of the data analysis. Olasveengen and Sunde have contributed to the concept and design of the study. Acquisition of data was performed by Wik, Lund-Kordahl and Lorem. Analysis and interpretation of the data were done by Lund-Kordahl, Olasveengen and Sunde. Lund-Kordahl, Olasveengen and Sunde have drafted the manuscript. Critical revision of the
Financial support
The study was supported by grants from Eastern Norway Regional Health Authority, Oslo University Hospital Ulleval, Norwegian Air Ambulance Foundation, Laerdal Foundation for Acute Medicine, Anders Jahres Fund.
Conflict of interest statement
Olasveengen has received honoraria from Medtronic (Oslo, Norway) and research support from Laerdal Medical Corporation (Stavanger, Norway). Wik is on a Medical Advisory Board for Physio-Control, has in the past consulted for Physio-Control, Zoll, Laerdal and Jolife, and is the principle investigator for a multi-centre mechanical chest compression device study sponsored by Zoll. Lund-Kordahl, Lorem, Samdal and Sunde have no conflicts to declare.
Acknowledgements
We thank all physicians and paramedics working in the Oslo EMS Service as well as Ståle Nygård for assistance with the statistics and Petter Andreas Steen for invaluable help in preparing the manuscript. The study was supported by grants from Eastern Norway Regional Health Authority, Ulleval University Hospital, Norwegian Air Ambulance Foundation, Laerdal Foundation for Acute Medicine, and Anders Jahres Fund.
References (35)
- et al.
An alternative approach to advancing resuscitation science
Resuscitation
(2005) - et al.
Cardiopulmonary resuscitation by lay people
Lancet
(1976) - et al.
Quality assessment of defribrillation and advanced life support using data from the medical control module of the defibrillator
Resuscitation
(1999) - et al.
Long term survival and costs per life year gained after out-of-hospital cardiac arrest
Resuscitation
(2004) - et al.
Effect of implementation of new resuscitation guidelines on quality of cardiopulmonary resuscitation and survival
Resuscitation
(2009) - et al.
Implementation of a standardised treatment protocol for post resuscitation care after out-of-hospital cardiac arrest
Resuscitation
(2007) - et al.
Ventricular fibrillation in King County, Washington: a 30-year perspective
Resuscitation
(2008) - et al.
Effects of compression depth and pre-shock pauses predict defibrillation failure during cardiac arrest
Resuscitation
(2006) - et al.
Quality of out-of-hospital cardiopulmonary resuscitation with real time automated feedback: a prospective interventional study
Resuscitation
(2006) - et al.
Is CPR quality improving? A retrospective study of out-of-hospital cardiac arrest
Resuscitation
(2007)
In-hospital factors associated with improved outcome after out-of-hospital cardiac arrest. A comparison between four regions in Norway
Resuscitation
Post resuscitation care: what are the therapeutic alternatives and what do we know?
Resuscitation
Inter-hospital variability in post-cardiac arrest mortality
Resuscitation
Variation in outcome in studies of out-of-hospital cardiac arrest: a review of studies conforming to the Utstein guidelines
Am J Emerg Med
Epidemiology, trends, and outcome of out-of-hospital cardiac arrest of non-cardiac origin
Resuscitation
Decrease in the occurrence of ventricular fibrillation as the initially observed arrhythmia after out-of-hospital cardiac arrest during 11 years in Sweden
Resuscitation
2005 American heart association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care
Circulation
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A Spanish translated version of the abstract of this article appears as Appendix in the final online version at doi:10.1016/j.resuscitation.2009.12.020.