¿Es aplicable el sistema de vigilancia epidemiológica de las infecciones intrahospitalarias que recomienda el CDC-americano (sistema NNIS) en un hospital chileno? / Application of the national nosocomial infections surveillance system recommended by the CDC, in a Chilean hospital

ABSTRACT

Background: The National Nosocomial Infections Surveillance System (NNIS system) is the method for surveying nosocomial infections used by the Centers for Disease Control (CDC). This strategy allows the comparison of different hospitals, using rate adjustments. In Chile, this system is not used. Aim: To report the application of this system in a tertiary reference hospital in Chile. Materials and methods: We performed a six months prospective cohort study. The active surveillance was carried out by using the intensive care unit and surgery components of the NNIS system. Tabulation and analysis of the data were done according to the NNIS system. In a parallel prevalence study, we determined the NNIS system sensitivity to detect nosocomial infections. Results: A total of 492 patients were followed with a global nosocomial infection rate of 14 per cent, for discharged patients. The calculated sensitivity and specificity of the system was 84.2 and 97 per cent respectively. In the intensive care unit, 45 of 169 patients had nosocomial infections, with an adjusted rate of 2.8 per cent for mean hospitalization time and severity of illness. In the cardiovascular and thoracic surgical units, 216 and 107 procedures were surveyed, respectively. The global rates of nosocomial infections were 7.4 and 7.5 per cent, respectively. The adjusted rates according to risk factors were 0.9 and 2.3 per cent, respectively. Conclusions: These data indicate that the surgical units had surgical site infections rates similar to those reported by the CDC. Nosocomial infections rates in Chile can be compared with rates observed in other countries. The epidemiological data collected can be useful to focus intervention or preventive strategies