TOPLINE

Clean catheterization was noninferior to sterile catheterization in rates of suspected catheter-associated urinary tract infections (UTIs). The clean technique reduced the carbon footprint of catheterization sets by more than 70% compared with sterile methods.

METHODOLOGY

• Researchers conducted a retrospective noninferiority study of 3293 patients at a medical center in Netherlands to compare the rates of catheter-associated UTIs between a sterile catheterization phase (2023-2024) and a clean catheterization phase (2024-2025).
• The clean catheterization protocol utilized nonsterile gloves, nonsterile gauze, anesthetic gel, and tap water, replacing the sterile technique that included sterile gloves, gauze, drapes, and an antiseptic solution. Split into two groups (mean age, 62.5 years; 49.5% women), roughly equal halves were treated with sterile or standard protocols.
• Patients were considered to have a suspected catheter-associated UTI if they had an indwelling catheter, had a positive urine culture, and received antibiotic treatment from 2 days after catheter insertion through 7 days after removal.
• Researchers established noninferiority if the upper bound of the 95% CI did not exceed the noninferiority margin of 0.5 percentage points.
• They evaluated time trends in UTI occurrence using interrupted time series analysis and assessed the proportion of positive urine cultures, cultured microorganisms, and the carbon footprint of catheterization sets.

TAKEAWAY

• Suspected UTIs occurred in 3.8% vs 3.3% of patients during the sterile phase vs during the clean phase, with an adjusted risk difference of -0.44% (95% CI, -1.4% to 0.5%), meeting the noninferiority criteria.
• Interrupted time series analysis showed no significant preintervention or postintervention trends. Positive urine cultures were identified in 13.1% of patients in both phases.
• Escherichia coli was the most frequently cultured organism in both groups (31.6% vs 27.2%), followed by mixed flora and Klebsiella pneumoniae.
• The carbon footprint of the clean set was 70.7% and 82.3% lower than that of sterile sets used in emergency rooms and operating rooms, respectively, equivalent to an estimated annual reduction in carbon footprint of approximately 1300 kg carbon dioxide equivalent based on 3293 catheterizations.

IN PRACTICE

“Given the absence of increased catheter-associated urinary tract infection risk and the substantial reduction in carbon footprint, routine sterile catheterization for standard in-hospital urinary catheter placement may represent low-value care. Our findings suggest that clean catheterization may be considered as a safe alternative default practice,” the authors of the study wrote.

SOURCE

The study was led by Stijn Bluiminck, Radboud University Medical Center, Nijmegen, Netherlands. It was published online on July 2, 2026, in BMJ Open.

LIMITATIONS

Relying on a case definition on the basis of clinical and laboratory data could have resulted in misclassifications, including in patients with asymptomatic bacteriuria. The analysis only included each patient’s first catheter-associated UTI episode. Immunocompromised patients or those needing guidewire catheterization could not be identified and excluded.

DISCLOSURES

The study received support from Betaalbaar beter and VGZ. No specific author conflicts of interest were detailed in the study.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.