Therapeutic hypothermia after cardiac arrest: implementation and outcome in Finnish intensive care units

Background: Therapeutic hypothermia (TH) has been shown to increase survival after out-of-hospital resuscitation. The aim of our study was to find out nationwide implementation and the actual utilization of TH after cardiac arrest in Finnish intensive care units (ICUs). We also determined the outcomes and describe demographic variables of the patients treated with TH. Methods: We analyzed a nationwide prospective database and included all adult patients (1555) treated in ICUs after cardiac arrest during 2004 and 2005. Results: During 2004 and 2005, 407 patients were treated with TH and TH was used in 19 out of the 20 ICUs. The proportion of cardiac arrest patients treated with TH had increased from 4% in 2002 to 28% in 2005. The incidence of cardiac arrest patients admitted to ICUs was 15/100,000 inhabitants/year. The use of TH varied in different areas of the country from 3.4 to 5.0/100,000 inhabitants/year. In-hospital mortality of TH patients was 32.7% and increased from 13.2% in age group < 45 years to 46.0% in age group > 75 years (P = 0.0002). Six-month survival was 55.3%. Median (interquartile range) length of stay in the ICU was 3.7 (2.7-5.3) days. Conclusion: In Finland, TH is implemented in almost all ICUs but it is applied only to a selected group of patients. Six months after cardiac arrest, more than half of the patients treated with TH were alive. Among patients treated with TH, younger patients had lower in-hospital mortality.