Denominator Matters When Reporting CAUTIs, Researchers Say

Researchers who evaluated two different methods of measuring catheter-associated urinary tract infection (CAUTI) rates in the setting of a quality improvement initiative aimed at reducing device utilization conclude that using device-days as a method of risk adjustment to calculate device-associated infection rates may mask the impact of a successful quality improvement program and reward programs not actively engaged in reducing device usage.

Marc-Oliver Wright, MS, CIC, of the Department of Infection Control at NorthShore University HealthSystem in Evanston, Ill., and colleagues, compared CAUTI measurements in the context of a before-after trial of acute care adult admissions to a multicentered healthcare system. The researchers identified CAUTIs with an automated surveillance system, and device-days were measured through an electronic health record. Traditional surveillance measures of CAUTI rates per 1,000 device-days (R1) were compared with CAUTI rates per 10,000 patient-days (R2) before (T1) and after (T2) an intervention aimed at reducing catheter utilization.

Wright, et al. report that the device-utilization ratio declined from 0.36 to 0.28 between T1 and T2 (), while infection rates were significantly lower when measured by R2 (28.2 vs 23.2, ). When measured by R1, however, infection rates trended upward by 6 percent (7.79 vs. 8.28, ), and at the nursing unit level, reduction in device utilization was significantly associated with increases in infection rate. Their research was published inthe July issue of Infection Control and Hospital Epidemiology.

Reference: Wright MO, Kharasch M, Beaumont JL, Peterson LR and Robicsek A. Reporting Catheter-Associated Urinary Tract Infections: Denominator Matters. Infect Control Hospital Epidem. Vol. 32, No. 7. July 2011.