Device associated nosocomial infection: a surveillance in an intensive care unit

ABSTRACT

This study was carried out in The Intensive Care Unit [ICU] at Menoufiya University Hospital from January 1997 to April 1998 to study the device-associated infection rate as an extrinsic risk factor for nosocomial infection in ICU and to compare this rate with infection rate based on patient admission and patient days in the unit. All intensive care patients were surveyed daily and all cases were examined clinically and with laboratory investigations including sputum, blood and urine cultures in the clinical pathology laboratory of the unit. Data were recorded on the National Nosocomial Infection Surveillance [NNIS] component form. The results revealed that the patient admission infection rate was 16.5% [140 cases out of 870 patients]. When the patient days were used as denominator, the infection rate was 46.35/1000 patient days. On the other hand, when device days were used as denominator, the device-associated infection rate was 31.63/1000 device days. These rates vary by type of patient in ICU and type of device utilized, the surgical ICU patients [SICU] had significantly higher pneumonia rate compared to medical ICU [MICU] [91.8 versus 54.7/1000 ventilator days, p <0.05]. Also, central intravenous-associated bacteremia rate was significantly higher in SICU compared to MICU [33.64 versus 12.93/1000 intravenous catheter days, p<0.05]. While urinary tract infection rate was significantly higher among patients in MICU compared to surgical one [32.18 versus 19.5/1000 urinary catheter days, p <0.001], which may be attributed to the prophylactic use of antibiotics among surgical patients. As regard sputum, blood, urine cultures. Gram-negative bacteria were found to be the most common organism recovered from ventilator-associated pneumonia, central intravenous catheter-associated bacteremia and catheter-related urinary tract infection [54.5%, 54.2%, 47.9% respectively]. It was found that perfect and effective hand washing significantly reduced catheter-associated intravenous bacteremia from 26.6 to 8.2/1000 catheter days and urinary tract infection rate from 25.3 to 10/1000 catheter days. So, we recommend urgent establishment of nosocomial infection control committee in Menoufiya University Hospital and more emphasis on the effective technique of hand washing as it is proved to be the simplest measure in controlling device-associated nosocomial infection in ICU. In the meantime, sterilization of equipments should be stressed with every step and each manipulation