RESUMO
The goal of surveillance is to identify hospital-acquired infections (HAI) and risk factors, to apply targeted interventions and to evaluate their effect in an ongoing system. Continuing active surveillance in a 270-bed acute-care hospital is being performed on clinical patients, excluding day-care. The period 1984-1997 is described here. Specific surveillance-based interventions included the introduction of antimicrobial prophylaxis in gynaecology patients with postoperative urinary tract catheters and inpatients scheduled for appendicectomy and hysterectomy. General measures included education, implementation of protocols, feedback of surgeon-specific infection rates. In total, 3545 HAI were found in 13 years of surveillance. The incidence was 4.7/100 admissions and 4. 5/1000 patient days. Age-specific incidences ranged from 1.3 in the age-category 1-14 years, to 10.2 in patients aged 75 years and above. If age-specific incidences had remained at their 1984 level, over 3000 additional infections would have occurred, affecting all age groups except those up to 14 years. The distribution of types of infections differed between services. Following the targeted interventions, the rate of infections in gynaecology decreased from 19.4 per 1000 patient days in 1984 to 2.4 per 1000 patient days in 1996. The rates of wound infection following appendicectomy and hysterectomy decreased by 69% and 82%, respectively, in the period following the institution of antimicrobial prophylaxis. Over 4000 micro-organisms were isolated from the HAI; multi-resistant strains were isolated sporadically. We conclude that hospital-wide surveillance of hospital-acquired infections provides appropriate targets for interventions tailored to the specific needs of the hospital. The impact of such interventions can readily be documented from the surveillance data.