An extra step to reduce urine cultures

New containers allowed clinicians time to think before culturing.


Background

At Michael Garron Hospital, nurses can order urine cultures under a medical directive, which was leading some patients to receive antibiotic treatment for asymptomatic bacteriuria. “Nurses were getting a urine specimen and automatically ordering a culture, and then when the culture would come back a day or two later positive, even if the diagnosis by the admitting doctor was, let's say, worsening confusion, failure to thrive, dementia . . . it would be hard for that physician not to start antibiotics,” said Maureen T. Taylor, BHSc, a physician assistant in the hospital's division of infectious diseases.

In the past, the hospital tried many different ways of educating nurses about when to order a urine culture, she said. “But studies show . . . that those educational attempts have all failed, and we have not been able to reduce the number of urine cultures ordered,” Ms. Taylor said. For its next attempt, the hospital implemented a two-step ordering process for urine cultures and switched to a new type of specimen container.

How it works

Under the two-step process, nurses could still collect urine cultures based on clinical symptoms, but samples would not be sent to the laboratory for testing until the treating physician concurred and entered a separate order. Urine cultures were held at room temperature for up to 48 hours, which was made possible through a preservative in the new specimen container.

The team leading the project educated physicians and nurses about the new ordering process, but not specifically about indications for ordering urine cultures. “We had to tell physicians, ‘Don't automatically assume that you're going to have the results of the urine culture the day after the patients are admitted anymore, because you personally have to go in and make that happen with a second click of the button,’” Ms. Taylor said.

Results

The new system was initially applied in the ED, where it was associated with reductions in the number of urine cultures sent for processing, she reported. It was next tested on inpatients and was associated with a nearly 50% reduction in the number of processed urine cultures (2.29 vs. 1.17 per 100 patient-days), according to results published as a research letter in February by JAMA Network Open. It was also associated with a reduction in the detection of asymptomatic bacteriuria and candiduria. There were no changes in antimicrobial use from the preintervention period to the postintervention period, according to Ms. Taylor, who was lead author of the study.

Anecdotally, Ms. Taylor said she has noticed that more nurses are realizing when their orders don't make it to step two. “And now, we're noticing less [ordering]. They're using more clinical judgment as well, because they don't want to order something that's never going to go anywhere,” she said. “Just because there is a test doesn't mean we have to do it, and there are harms to the patient when we do it unnecessarily.”

Challenges

One of the tricky parts of the intervention was making sure not to reduce nurses' autonomy. The researchers thought it was important not to remove their ability to send for a culture altogether, Ms. Taylor said. “We didn't want nurses to feel that this was a criticism of their clinical judgment,” she said.

Words of wisdom

The absence of a reduction in antibiotic use is likely due to the hospital's focus on not treating asymptomatic bacteriuria over the past few years, Ms. Taylor noted. “In hospitals that don't have a great antimicrobial stewardship team, they may actually be able to show a reduction in antibiotic use,” she said, “because you would think that there are physicians ordering antibiotics for asymptomatic bacteriuria. If you had this kind of two-step program, it would force those physicians to really think twice before even sending it for culture.”

Next steps

The two-step ordering process is still in effect, and the hospital continues to use the special urine containers, Ms. Taylor said. (The company that makes the containers did not provide funding or assist with the design of the study.) “We know we're saving the hospital money by not having those urine cultures processed, and so we're using [the process] in the emergency department and throughout the hospital,” she said.