Catheter-associated urinary tract infections (CAUTIs) can have a significant impact on U.S. healthcare organizations. One study showed a mean extra cost of $589 per CAUTI due to diagnostic and medication expenses.1
Given the frequency of these infections, costs can add up quickly. Hospital-acquired urinary tract infections are the most common hospital-acquired infections in the Untied States, says Sanjay Saint, MD, MPH, associate professor of internal medicine at the University of Michigan Medical School, and acting chief of medicine at the VA Ann Arbor Healthcare System. It has been reported that more than 1 million cases of CAUTI occur each year in U.S. hospitals and nursing homes.2
CAUTIs are likely to resolve spontaneously with the removal of the catheter.3 Occasionally, an infection can lead to complications such as prostatitis, epididymitis, cystitis, pyelonephritis, and gram-negative bacteremia, particularly in high-risk patients. Gram-negative bacteremia is associated with significant mortality, but only occurs in less than 1 percent of catheterized patients.
Fortunately, most patients with a hospital-acquired urinary tract infection will be asymptomatic, Saint comments. However, in up to 20 percent of patients, there will be symptoms of a urinary tract infection, and up to 3 percent of patients will develop bloodstream infection, or bacteremia. Most patients with hospital-acquired urinary tract infections have some type of urinary catheter, and one in every four patients hospitalized in the Untied States has an indwelling catheter sometime during their stay. In aggregate, catheter-related urinary tract infections remain an important cause of morbidity and economic cost in the United States.
Saint explains that infections will generally occur in one of three ways. First, at the time of indwelling catheter insertion, and thats why proper technique is so important. Once the catheter is in place, it will occur either by intraluminal spread, where the drainage bag gets colonized and then bacteria spreads intraluminally into the bladder, or finally with colonization on the outside portion of the catheter, with migration of bacteria into the bladder via an extraluminal route.
An investigation of the pathogenesis of new-onset CAUTIs and the importance of each possible mechanism of infection discovered that the majority of cases (66 percent) were extraluminally acquired.4 The study found that 34 percent of the infections were caused by intraluminal contaminants. Gram-positive cocci, such as enterococci and staphylococci, and yeasts were much more likely to be acquired extraluminally than gram-negative bacilli. Gram-negative bacilli caused CAUTIs via both routes of infection. Another interesting finding from this study was that the pathogenic mechanisms were not found to be significantly different between men and women.
In terms of risk factors for bacteriuria, studies have found that patients who are older are at higher risk, women are at higher risk, and some studies have found that patients with diabetes mellitus are at higher risk, Saint points out. Patients on systemic antimicrobials appear to have a lower risk of bacteriuria, and we have recently found that there are also risk factors for bacteremia in those who are already bacteriuric. Some of those risk factors for bacteremia in patients who are already bacteriuric include patients who are receiving immunosuppressant medications, patients with known malignancy, and patients who smoke cigarettes. We are hoping to do a larger study to confirm some of these findings.
The discussion about preventing CAUTIs must begin with proper hand hygiene and adherence to general infection prevention and control recommendations, Saint asserts. In terms of factors that are more specific to nosocomial UTI, the most important thing is to only catheterize patients who absolutely need an indwelling catheter, and once the catheter is in place, remove it as soon as possible as soon as the indication for a catheter is no longer present, he continues. Because that is easier said than done, there are ways of systematizing that approach; one of them is having a computerized physician order entry (CPOE) system that reminds the physician when a patient has an indwelling catheter for example, for two days and will automatically remove the catheter unless the physician re-orders it. That has been studied at the Seattle VA Medical Center.
Saint notes that similar options do exist for facilities without a CPOE system. We at the University of Michigan, because we dont yet have computerized physician order entry, have studied a written reminder placed on the medical chart that reminds physicians that their patients have indwelling catheters and then they can either continue it or discontinue it. We also found that this simple approach reduced urinary catheterization. Finally, a recent study found that a nurse-based reminder system, where nurses remove the catheter when its no longer needed, also reduced urinary catheterizations and reduced UTIs. There are many different approaches a hospital can decide to take.
At the Yale-New Haven Hospital, a program was designed to address CAUTIs.5 The first step was to increase physician awareness that an indwelling urinary catheter had been placed in patients by the emergency department (ED), and to encourage physicians to minimize the duration of catheter use. This was done using the facilitys CPOE system. Documentation of catheter insertion in the ED was added to the floor nursing report, and an alert was sent via CPOE to the physician as part of the admission orders. The physician would then be prompted to discontinue the device, maintain the catheter for 48 hours, or maintain the device chronically.
Another important component of this effort involved the development of a nurse-driven protocol that gave nurses the ability to discontinue a catheter, independent of a physicians order, when a patient no longer met established criteria for catheter use. Nurses were educated on alternatives to indwelling catheters, including intermittent catheterization, bedside commode use, condom catheters, and/or voiding trials for incontinent patients. Additionally, nurses were able to use bladder scanners to non-invasively determine whether or not urinary retention was present.
Six months after these interventions were established, a 51 percent reduction in patients admitted with indwelling catheters was seen, and device days decreased by 42 percent compared to baseline data. The percentage of catheters placed that did not meet criteria for appropriate use decreased from 24 percent to 14.8 percent. In terms of CAUTI incidence, a 47 percent decrease was realized. The authors cite the collaboration among physicians and nurses as a vital component of their success. Shared accountability and responsibility between the two groups was consciously promoted, rather than falling into the pattern of assessing blame for inappropriate catheter use.
Another study showed that simply providing nursing staff members with a quarterly report detailing CAUTI rates was effective in combating the infections.6 In this case, 32 infections occurred in 1,000 catheter-patient-days during the first quarter of the pre-intervention period. In the 18 months that followed the intervention, the mean UTI rate decreased to 17.4 per 1,000 catheter-patient-days, which resulted in an estimated a cost savings of $403,000.
The use of anti-infective urinary catheters is another tactic that hospitals may employ to decrease CAUTI rates. If a hospital is still having a high infection rate after doing some of the things Ive already discussed proper hand hygiene, general infection control principles, early removal of urinary catheterization then anti-infective catheters are another method to consider, especially in patients who are at high risk for infection, Saint says.
A systematic review of the effectiveness of antimicrobial urinary catheters in preventing CAUTIs showed that these devices can prevent bacteriuria in hospitalized patients during short-term periods of catheterization, depending on variables such as antimicrobial coating.7
Nitrofurazone-coated silicone or silver-coated latex catheters were compared to silicone or latex catheters. The authors noted that the study was limited by a lack of trials comparing nitrofurazone-coated catheters to silver alloy-coated catheters.
Saint points out that the use of devices other than indwelling catheters can be beneficial in some circumstances. In men who require urinary collection and in whom an external or condom catheter would be appropriate, it seems like the risk of infection is lower if that individual does not have cognitive impairment, he says. The consideration should be made to use condom catheters in men who are not cognitively impaired. The reason is that cognitively impaired individuals are more likely to remove their catheter unnecessarily, and that frequent manipulation may in fact increase the risk of infection.
Future research into methods of CAUTI prevention will be based on large-scale, randomized, controlled trials occurring at multiple hospitals in which clinical efficacy and cost effectiveness are determined, according to Saint. Many of the interventions involve new products that are more costly, therefore both efficacy and efficiency need to be considered by decision makers, he adds. Also, I think that well see studies on how new innovations diffuse throughout the healthcare system. Why is it that one hospital is doing everything that is recommended while another hospital is not? What are the facilitators and barriers of translating research findings into practice? I think this will be true not only of nosocomial UTIs, but hospital-acquired infections in general, including ventilator-associated pneumonia and vascular catheter-related infections.
A Case Study
At Barnes-Jewish Hospital, which is a 1,400- bed facility based in St. Louis, a simple intervention made a big difference in preventing CAUTIs in a post-intensive care rehabilitation unit. These are basically patients who have been in the hospital for months or even years, says Loie Ruhl, RN, BS, CIC, infection control specialist at Barnes-Jewish Hospital. Theyre vented, and they usually have catheters if theyre not getting dialysis. When she took over the unit, Ruhl looked into the UTI rates. She recalls that the first month she looked at showed a rate of approximately 27 infections per 1,000 catheter days. I then went back and looked at the whole year, I did a retrospective review, and the mean was 22.7, with a range from 11.6 to 46.5.
Because the unit is rather unusual, Ruhl had no national benchmark to compare the rates to, but she still knew that a mean of 22.7 was very high. At a staff meeting in the second half of 2003, she initiated a discussion about the problem and potential ways to address it. We did some brainstorming at this staff meeting, and wondered what would happen if we decided to increase perineal care for these people. Of course, everybody usually wants to look at the newest, highest technology, antimicrobial devices that are on the market, but we thought we would start with something simple that we could do that nobody would even have to be aware of.
The decision was made to focus on perineal care; it would now be performed three times per day. Ruhl says the pay-off was almost immediate. The rates dropped dramatically we went from a mean of 22.7 to a mean of 7.3, she notes. We have continued to do this and have sustained the results for two years. We used the silver catheters already, and they do a lot, but theres only so much they can do, especially when these people have the catheters in for months at a time. This effort is something that started out innocently enough, but the success has just been remarkable. With any intervention, usually you can sustain rates for six months, and then you see the old habits come back, but I worked with the staff and made sure they remembered to do this. They also made it a part of new employee orientation, so they are very aware of catheter-associated urinary tract infections. In fact, one month they called me before I had even calculated rates (the month wasnt over yet), and said, Our rates are up you need to come back up to teach everybody again and remind us about this. They have taken ownership of this intervention and made it a part of their daily practice, and have sustained tremendous results.
Ruhl made a point of making the initiative a collaborative affair in her initial educational effort. I think its important when youre doing something like this to include staff in the decisions, because if you just go up there and say, You need to do this, then its probably not going to happen, she says. Because they were part of the decision, they basically said, Lets try this, and if it doesnt work we can move on and try something else. After the first month that we tried it, the rate dropped from 17.9 to 13. The following month, we had zero, so they could really see that this was doing something. In 2004 our mean was 7.3, in 2005 it was 8, and now its 5 so far for 2006. They have sustained it and its become common practice its just what we do. When they could see immediate results, it made a huge difference.
While perineal care has made a significant impact, Ruhl stresses the need for a continuous focus on the basics as well. We obviously make sure that catheters are inserted using aseptic technique and that the system remains closed, and we use the silver catheters, but those are things we were already doing, she says. Thats the standard of care. This was something that was very simple with no cost involved, not high-tech at all, yet the staff was able to see such dramatic results with it that they wanted to do it. Recognition of the units success and of the efforts of staff members in this respect by the rest of the hospital has also been rewarding. It did a lot for morale as well, because theres a lot of difference in terms of how people look at the various units in the hospital. We all sort of stumbled through this together and it just blossomed and became such a wonderful thing, and to see the lower rates on the floor and to see the staff so aware of it and taking such ownership of it has been great.
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