Bladder Pressure Measurements Are an Independent Predictor of Urinary Tract Infection in Trauma Patients

Abstract

To determine the risk factors for urinary tract infections (UTIs) specific to trauma patients in order to assist in the development of infection control protocols. Data were collected prospectively from January 2003 until December 2005 by an epidemiology nurse and combined with registry data from our Level 1 trauma center. The trauma patients admitted to the Surgery and Trauma Intensive Care Unit (STICU)(n = 938) who did and did not have UTIs were compared for demographics, Injury Severity Score (ISS), and epidemiologic data, including use of Foley catheters and bladder pressure measurements (BPMs). An open system was used for the measurements in which the catheter was disconnected from the bag to instill 50 mL of saline into the bladder, and an 18-gauge needle was inserted into the catheter to measure the pressure. A total of 50 patients had no Foley catheter or UTIs. Among the 836 patients with catheters but no BPMs, there were 36 UTIs (4.31%), whereas the 52 patients with catheters and BPMs had 12 UTIs (23.08%)(p < 0.0001). Patients with UTIs were more severely injured older females (mean age 40.1 ± 18.6 years with no UTI vs. 48.5 ± 20.8 with UTIs; p = 0.0083; percent female 26.4 no UTI vs. 45.8 UTI; p = 0.007; ISS 19.3 ± 11.3 no UTI vs. 26.2 ± 11.6; p < 0.0001). Using logistic regression, BPM was an independent predictor of UTI, with infection being seven times more likely in the patients having the measurements (odds ratio [OR] 6.99; 95% confidence-interval [CI] 3.087-15.827). Along with age (OR 1.039; CI 1.024-1.054) and ISS (OR 1.081; CI 1.056-1.106), having BPMs was an independent predictor of death (OR 2.475; CI 1.191-6.328). This is the first study that demonstrates a greater risk of UTI with BPM using the open technique independent of patient gender or degree of injury. Given these findings and a previous trial demonstrating no difference in UTI rates with a closed circuit for BPM, our institution has incorporated a closed circuit technique into its infection control protocol.