Sentinel system for nosocomial infections in The Netherlands: a pilot study.

Objective: To determine the feasibility of standardized surveillance of nosocomial infections (NI) in The Netherlands, using local data on patients with NI collected by infection control practitioners (ICPs) and denominator data on all patients under surveillance obtained from the Dutch National Medical Registry (LMR).

Design: A prospective, multicenter study.

Setting: Eight hospitals in the Utrecht region, and the National Institute of Public Health and the Environment.

Patients: ICPs traced NI in gynecological and orthopedic patients for 9 to 16 months. Denominator data on all patients under surveillance were obtained from the LMR.

Results: Data from 8,922 patients were collected; the ICPs registered 470 patients with 526 NI. Overall, the NI incidence was 5.9 per 100 patients, or 6.3 per 1,000 patient days. Urinary tract infections (UTI) were most frequent (3.3%), followed by surgical-wound infections (SWI; 2.0%) and bloodborne infections (0.12%). The incidence of both SWI and UTI differed markedly between hospitals, only partially on account of differences in patient mix (age, type of operations), antibiotic prophylaxis, and intensity of tracing methods for NI. Delay in the availability of denominator data hampered the timely feedback of incidence figures.

Conclusions: Surveillance of NI in a network of sentinel hospitals offered valuable information on the occurrence of NI and on factors influencing the incidence of NI. It revealed situations in which both NI surveillance and infection control methods in individual hospitals should be improved. Obtaining denominator data on all patients from electronically registered patient discharge data greatly reduces the workload of ICPs and enables surveillance on all types of NI (all body sites and all pathogens). For timely feedback, numerator and denominator data within hospitals must be linked.