Severe sepsis and septic shock: a prospective population-based study in Icelandic intensive care units

Background: The aims of our study were to describe the nationwide epidemiology of sepsis requiring intensive care during an entire year and to evaluate compliance with treatment guidelines. Methods: This was a prospective, observational study of all adult patients admitted to Icelandic intensive care units (ICUs), who were screened for the ACCP/SCCM criteria for severe sepsis or septic shock on admission. Data were collected from 1 April 2008 to 31 March 2009. Results: One thousand five hundred and twenty-four patients were admitted to the ICUs during the study year, 115 of them because of severe sepsis or septic shock. The incidence in Iceland was 0.48/1000 inhabitants >= 18 years per year [95% confidence intervals (CI) 0.42-0.55]. The mean APACHE II score was 20.7. Mortality was 24.6% (95% CI 17.5-33.3) at 28 days and 40.4% (95% CI 31.8-49.5) at 1 year. The main sources of infections were pulmonary (37%), abdominal (28%) and urinary tract (8%). Pathogens were gram-positive (39%), gram-negative (30%) and mixed (28%). No patient had sepsis caused by methicillin-resistant Staphylococcus aureus or a monomicrobial fungal infection. Pulmonary infections were an independent predictor of death. Compliance to the resuscitation goals of the Surviving Sepsis Campaign ranged from 60% to 72% and the 6-hour Sepsis Bundle was completed in 35% of patients. Conclusions: This nationwide study showed an incidence of 0.48/1000 inhabitants for severe sepsis and septic shock requiring intensive care therapy. The 28-day mortality rate of 25 % was in the lower range of previous reports but the compliance to resuscitation goals and sepsis bundles was similar.