The Burden of Nosocomial Infection in the Intensive Care Unit: Effects on Organ Failure, Mortality and Costs. A Nested Case-Control Study

BackgroundNosocomial infections increase mortality and costs in the intensive care units; however, few studies have addressed organ failure that developed in infected patients and their overall costs. The goal of this study was to measure the frequency of organ failure in nosocomial infection and the mortality and costs of these in critical care areas.MethodsThis was a nested 1:2 case-control study in a cohort of all consecutively hospitalized patients comparing those with and without nosocomial infections over a year in an institutional intensive care unit (ICU). Those patients who acquired an infection during hospitalization were considered cases. Controls were matched by hospital stay at least as long as the cases' time acquisition of nosocomial infection, age ±5 years and APACHE II ±5 points.ResultsForty-three patients developed at least one nosocomial infection event (cases). The matching success was about 94%. Higher frequency and duration of organ failures was observed in the cases, as well as the number of devices and procedures (p <0.05). Attributable mortality was 16.3% (p <0.001). Attributable total cost of a nosocomial infection acquired in the ICU was $12,155.ConclusionsNosocomial infection acquired in the ICU increases length of stay, frequency and duration of organ failures, mortality, and costs.