Catheter caps cut CLABSIs

NorthShore University HealthSystem in Illinois reduced its infection rate by 52%.

Where: NorthShore University HealthSystem, a four-hospital, university-affiliated health system in the northern suburbs of Chicago.

The issue: Preventing central-line contamination and associated bloodstream infections.


Clinicians at NorthShore had been monitoring, and working on, their rates of central-line-associated bloodstream infections (CLABSIs) since 2007. By 2009, the rates were pretty good (1.45 per 1,000 line-days), but the health system's infection experts were still looking for further improvement.

“Most programs such as mine have vendors contacting us on a regular basis saying, ‘Hey, you really need to look at this [device].’ The problem is that it doesn't mean it actually works,” said Marc-Oliver Wright, MS, corporate director of infection control. But when a manufacturer contacted him about trying out a new catheter hub disinfection cap with a sponge saturated in 70% alcohol, he was interested.

“The actual design of a catheter hub with its corkscrew physique makes it hard to clean effectively,” he said. “You have to stop what you're doing [in the process of accessing the central line] and instead of giving the patient the drug, you have to stand there, and scrub, scrub, scrub for 15 seconds.”

To assess the effectiveness of this potential solution, Mr. Wright convinced the device manufacturer to let the health system conduct a three-phase trial of the caps.

How it works

The NorthShore team started their project by assessing current contamination rates in central lines to establish a baseline rate for comparison. After several months of monitoring, the new catheter caps, containing alcohol-soaked sponges, were threaded on to all central lines that were not actively in use. When a clinician wanted to use the line, he would remove and discard the cap. After the infusion was complete, a new cap was screwed on.

Each hospital had an education program about how to use the device itself, and continued to do quantitative blood cultures of the fluid in the line. Then, after about six months, the new caps were removed from one of the hospitals. This represented phase 3 of the effectiveness trial, intended to establish definitively whether the caps, not some confounder, were responsible for any improvements in contamination or infection rates. “We knew that once we took the device away and said to go back to scrubbing the hubs, if it was the device, we'd see an increase in infections,” said Mr. Wright.


NorthShore saw a drop in contamination and CLABSIs after implementation and a rise when the caps were taken away, according to results in the January American Journal of Infection Control. “Bacteria in the intraluminal space had dropped by about half and the organism density of samples that were positive was cut by 75%. We saw that the infection rate itself was cut by 52%. All of those findings were statistically significant,” said Mr. Wright.

A NorthShore cost-effectiveness analysis indicated that for about $60,000 per year in caps, the hospitals could make room for almost 13 more admissions per year, thanks to fewer extended stays for CLABSIs.

The intervention was also popular with clinicians. “You don't have to do anything before you access the line, except take it off and throw it away, which takes a half-second,” said Mr. Wright.


Because the device was so easy to use, forgetfulness and lack of education were the main challenges to consistent implementation. “We had to do a lot of compliance checks….Periodically, throughout the day, you might have someone come in there and draw a lab instead of contacting the [vascular access] team and forget to put a new cap on,” Mr. Wright said. “When we fell short, we did have to do some reinforcement, some re-education.”

Next steps and final thoughts

After seeing the results of the study, the health system's corporate infection control committee was convinced to make the caps part of the standard of care. “We had two of our hospitals go for more than a year without a single line infection,” said Mr. Wright. “Our line infection rate has stayed in the [range of] 0.5% of all patients with lines.”

It's possible that the caps don't prevent contamination or infections any better than thorough scrubbing would, said Mr. Wright. But if an intervention like this can make infection prevention substantially more convenient for clinicians, it can improve compliance enough to change outcomes.

“Many infection prevention activities—hand hygiene, putting on personal protective equipment, scrubbing the hub—they're all interrupters….It slows down a person's desired task,” he said.