Characteristics and outcomes of patients admitted to Spanish ICU: A prospective observational study from the ENVIN-HELICS registry (2006–2011)

Abstract Objective To describe the case-mix of patients admitted to intensive care units (ICUs) in Spain during the period 2006–2011 and to assess changes in ICU mortality according to severity level. Design Secondary analysis of data obtained from the ENVN-HELICS registry. Observational prospective study. Setting Spanish ICU. Patients Patients admitted for over 24 h. Interventions None. Variables Data for each of the participating hospitals and ICUs were recorded, as well as data that allowed to knowing the case-mix and the individual outcome of each patient. The study period was divided into two intervals, from 2006 to 2008 (period 1) and from 2009 to 2011 (period 2). Multilevel and multivariate models were used for the analysis of mortality and were performed in each stratum of severity level. Results The study population included 142,859 patients admitted to 188 adult ICUs. There was an increase in the mean age of the patients and in the percentage of patients >79 years (11.2% vs. 12.7%, P P vs. 11.6%, odds ratio = 0.931, 95% CI 0.883–0.982; P  = 0.008). Conclusion This study provides observational longitudinal data on case-mix of patients admitted to Spanish ICUs. A slight reduction in ICU mortality rate was observed among patients with intermediate severity level.