Benchmarking of urinary tract infection rates: experiences from the intensive care unit component of the German national nosocomial infections surveillance system

https://doi.org/10.1016/j.jhin.2011.01.021Get rights and content

Summary

The aim of this study was to investigate whether surveillance of symptomatic catheter-associated urinary tract infections (CAUTI) in intensive care units (ICUs) leads to reduced CAUTI rates. Data from the German national nosocomial infection surveillance system (KISS: Krankenhaus Infektions Surveillance Systems) from three starter periods were used for the analysis (1997–2000, 2001/2002, 2003 or later). For each period data from the first and third years of participation were compared. Pooled CAUTI rates were calculated by month of participation and a linear regression model was adapted. A total of 547 ICUs provided data to the KISS ICU component from January 1997 to June 2008. According to the study protocol 1966 symptomatic CAUTI cases from 267 ICUs were included in the analysis. When comparing the symptomatic CAUTI rates in the third and first years, the overall relative risk was 0.86 (0.77–0.96). A much smaller surveillance effect for CAUTI was observed compared with similar data for ventilator-associated pneumonia and primary bloodstream infections. A lack of awareness by many intensivists for CAUTI compared with the other two infection types may be responsible. Reducing symptomatic CAUTI is also possible however and including CAUTI in the overall ICU surveillance activities does not create a significant additional workload.

Introduction

Healthcare-associated infections are often responsible for morbidity, mortality, significantly prolonged hospital stays and increased costs. It can be expected that about 500 000 patients develop nosocomial infections annually in Germany, about 60 000–80 000 of them in German intensive care units (ICUs).1 In accordance with German law, many hospitals have started surveillance activities for patient groups at risk for nosocomial infections,2 but they have not been able to judge their infection rates without data comparison. The German National Reference Centre for surveillance of nosocomial infections was started in 1997 to create a nationwide surveillance system giving all hospitals the opportunity to perform surveillance of the most important nosocomial infections according to the same definitions and identical methods and to calculate comparable infection rates. It was called the Krankenhaus Infektions Surveillance System (KISS).3

The methods and definitions of the American National Nosocomial Infections Surveillance (NNIS) System4, 5 were used when creating the system, because it was already well established at this time in many US hospitals and in use in some European countries. The definitions of the US Centers for Disease Control and Prevention (CDC) for diagnosing nosocomial infections were translated into German and the NNIS methods were used as the basis for surveillance in ICUs.

Meanwhile the number of hospitals and departments participating increased from year to year. At the end of 2009, 614 ICUs from 418 hospitals were providing data for ICU KISS.

However, surveillance is time-intensive and there has been some debate as to whether the time spent on surveillance has been invested wisely. In the past we have shown a significant reduction effect for primary bloodstream infections (BSIs)6, 7 and ventilator-associated pneumonia (VAP)7, 8 by ongoing surveillance and feedback in ICU patients. Meanwhile we have an overview of about 12 years of ICU surveillance and are able to demonstrate reproducibility of this surveillance effect for central venous catheter (CVC) BSI and VAP.9 Because the surveillance effect has not been shown in the past for catheter-associated urinary tract infections (CAUTI) we wanted to investigate the development over time of this infection type, using the same methodology as applied in a recent reproducibility study.9

Section snippets

Methods

The goal of this analysis was the comparison of rates of symptomatic CAUTI according to CDC definitions in the ICU component of KISS. Because the CDC definitions for symptomatic CAUTI have changed during the study, we present the definitions used for patients aged >1 year:5

Results

A total of 547 ICUs provided data to ICU KISS from January 1997 to June 2008. Data from 1.9 million patients and 6.8 million patient-days were collected during this period. A total of 5243 symptomatic CAUTI was recorded. According to the study protocol which excludes all data from ICUs with ongoing participation after their first three surveillance years, 1966 symptomatic CAUTI cases (37.5%) were included in the analysis. Table I shows catheter utilisation rates and symptomatic CAUTI rates in

Discussion

Combining the data from all starter periods, we were able to show a significant reduction in CAUTI between the first and third years of participation. Compared with earlier data involving CVC-BSI and VAP investigated during the same surveillance period, the overall surveillance effect was highest for VAP (20% reduction) followed by CVC-BSI (17% reduction) and CAUTI (14% reduction).9 For the first two types of infection, significant reduction effects were also found in most of the individual

Conflict of interest statement

None declared.

Funding sources

None.

Cited by (0)

View full text