Infección nosocomial y mortalidad en el paciente anciano en una unidad de críticos polivalentes

Objective: to analyze the relation between age, mortality and nosocomial infection (NI) in a multipurpose critical care unit (CCU). Material and methods: we performed a prospective cohort study in 652 consecutive patients admitted to a CCU from January 1, 1996 to December 31, 2001 with a length of stay longer than 48 hours. The variables analyzed were age, incidence of NI, nosocomial pneumonia (NP), bacteraemia (NB), urinary tract infection (UTI), surgical wound infection (SWI), length of stay, and mortality. Multivariate analysis was used to estimate variables independently related to the risk of infection and mortality (p < .05, 95% confidence infernal). Results: the mean age was 51.5 years and 25% of the patients were older than 70 years. A total of 67.8% were male. The most frequent NI was NP. There were 134 patients with one NI (20.5% of admissions), 108 with two (16.5%) and 80 with three or more (12.2%). More than one NI was found in 58.4% of infected patients. NI was more frequent in younger patients in all locations except SWI. Overall mortality was 40.1% and mortality in elderly patients was 54%. The mortality risk increased 1.02 for each year of life. The risk of NP, NB and UTI increased 0.98, 0.98 and 0.97 for each year of life. The risk of SWI increased 1.01 for each year of life. Conclusions: age is a risk factor for mortality in the CCU, but reduces the risk of NI, probably because of the lower use of invasive techniques.