Infection Control Today - 04/2004: Mechanical Reduction

April 1, 2004

Mechanical Reduction of Catheter-Associated Urinary Tract
Infection Risk

By Maureen Carignan, RN

Urinary catheterization is a known
source of bacterial infections, which in the worst-case scenario can lead to
death. Numerous antimicrobial technologies have been utilized to reduce the
incidence of such infections, with varying rates of success. Somewhat overlooked is the contribution made by improved
mechanical securement of Foley catheters. In fact, preliminary evidence suggests
that securement methods, not antimicrobials, may be the most effective solution
to urinary tract infection. In addition, clinicians and institutions should note
that proper securement has no downside, a claim that cannot always be made for
antimicrobial catheter coatings. In sum, while more research is needed, superior
securement has shown such impressive potential for reducing catheter-associated
urinary tract infection (CAUTI) risk that institutions should make it central to
their strategy for addressing the issue.

Dimensions of the CAUTI Problem

Despite modest advances in controlling this problem, CAUTIs
remain a frustratingly frequent consequence of urinary catheterization. More
than 5 million patients every year will be catheterized in American acute-care
hospitals and nursing homes.1 Of those patients catheterized for more than seven
days, up to 25 percent will develop a CAUTI.1 Indeed, CAUTIs constitute the most
common nosocomial infection, comprising more than 40 percent of all
hospital-acquired infections.1

Beyond their ubiquity, CAUTIs are also dangerous and costly.
The second most common cause of nosocomial bloodstream infection, they have been
shown to nearly triple the risk of death at an institution.2 While these
infections do not extend hospitalization in most cases, they add roughly $500 to
$1,000 to direct, acute-care hospitalization costs.1 This may seem like a
relatively minor amount, but the large number of CAUTI cases multiplies the
impact tremendously.

Finally, patients with asymptomatic CAUTIs, who constitute the
majority of infected patients, are commonly treated with antimicrobial drugs.
While this strategy fights infection, it also selects for drug-resistant
pathogens. These bacteria are in turn the source of most nosocomial CAUTIs.1

Antimicrobial Prevention

Besides antimicrobial drugs, numerous antimicrobial practices
and technologies have been studied since the mid-1970s. The most effective of
these appears to be a silverhydrogel catheter, the Bardex I.C. Foley (Bard
Medical, Covington, Ga.). In studies with small sample populations, the Bardex
I.C. reduced CAUTIs by 26 percent, without causing antimicrobial resistance.1
While an important development, this technology clearly cannot eliminate a large
percentage of CAUTIs.

In small studies, two other medicated catheters both
significantly reduced CAUTIs, but the benefit was undercut by the selection of
bacteria resistant to the medications used.1

Research has been unable to establish benefit for several
other novel technologies, including a sealed junction between the catheter and
the collection tubing, and a catheter coated with silver oxide.1 Some other
anti-infective practices have also failed to prove their efficacy. Catheters have been soaked in
anti-infective solutions and antimicrobial lubricants have been used during
insertion. Anti-infective creams and ointments have been applied. Catheterized
patients have had their bladders irrigated with antimicrobial solutions, or had
anti-infective solutions added to their collection cases. There is logic to each
of these ideas, but none of them have demonstrated value.1

The Securement Solution

In contrast to the aforementioned approaches, the
effectiveness of one securement technology, StatLock Foley (Venetec
International, San Diego, Calif.), may offer dramatic results, according to
preliminary research and anecdotal reports. The device consists of a patented,
releasable locking mechanism that swivels. The mechanism is affixed to an
adhesive foam pad placed on the patients skin. Among the reports of its
effectiveness:

  • A continuing care facility in Northern California
    conducted a sixweek clinical trial of StatLock in an attempt to reduce its CAUTI
    rate. The facilitys CAUTI rate had averaged 3.46 percent in the
    four months preceding the trial. Administration viewed this as an unacceptably
    high level, considering that it occurred despite use of the above-mentioned
    Bardex I.C. Foley catheter. For the six-week trial period, all patients with
    Foley catheters (23 males and females) had their catheters secured with
    StatLock. No CAUTIs occurred in the StatLock-secured patients. Following the
    trial, the facility returned to its original practice of not securing Foley
    catheters. The CAUTI problem reappeared; for the two-week period after the
    trial, the rate was 4.93 percent.3
  • At the Clark-Morrison Childrens Urological center at
    UCLA, Foley catheters were secured with tape prior to adoption of StatLock. Staff suspected tape securement was contributing to the centers
    CAUTI problem because the sticky surfaces of the tape tended to accumulate
    contaminants that were difficult to remove, exposing patients to infection risk.
    In addition, tape-secured catheters almost inevitably dislodged, and made it
    difficult for patients to ambulate after surgery without the catheters pulling
    on their bladders. StatLock dramatically improved each of these situations. It
    made it easy to clean catheters and eliminated the problem of tape
    contamination. Catheter dislodgements ceased, and catheterized patients were
    able to move more freely because the device was engineered to move with them.4
  • These results must be viewed in proper context. The
    evaluation at the Northern California facility was a preliminary study with a
    small patient sample. The results at the Clark-Morrison center are anecdotal. While suggestive, these data are not definitive. They point to
    the need for a prospective, randomized, multi-center trial that would
    conclusively determine whether a Foley-specific adhesive anchor device could
    reduce CAUTI risk.
  • Given the importance of cost control in todays
    competitive health marketplace, it would also be helpful to determine the
    financial benefit, if any, that adequate securement can provide institutions. Again, preliminary data suggests that the impact can be
    substantial if CAUTIs can be completely or nearly eliminated. Compare the cost
    of the StatLock device ($2.99) to the cost of treating CAUTIs (see Dimensions
    of the CAUTI Problem above), and then consider the prevalence of infections.
    The potential for large savings is obvious.

Other Benefits of Proper Securement

When clinicians consider whether to alter protocols to include
Foley catheter securement devices, they should note the additional benefits that
these devices can confer. For example, eliminating tape securement helps protect
healthcare workers. A study reported in The American Journal of
Anesthesiology
has established that tearing tape creates microtears in latex
gloves.5 Tears expose workers to infection risk.

The StatLock device has also been shown to help prevent
Carignans Syndrome, as described by the current author and Linda Nelson, RN,
BSN. This dangerous syndrome occurs post-operatively when patients
with inadequately secured in-dwelling urinary catheters wake from anesthesia. Traction on the catheter causes the catheter to slip into the
bladder neck during surgery, causing extreme pain and agitation, high blood
pressure, accelerated heart rate, occasional aberrant heart beats, and
aggressive behavior. First identified at Royal Columbian Hospital (New
Westminster, British Columbia), the syndrome vanished when staff implemented
StatLock in conjunction with hooking the urinary drainage bag to the OR table.6

Finally, the selection of an appropriate, effective device
like StatLock avoids the complications caused by less effective or problematic
securement methods. Some of the problems of tape securement have already been
mentioned. In addition, tape allows painful movements and traction because it
deteriorates over the course of just a few hours. Those same movements and
tensions can also cause tissue trauma. Finally, tape can cause local skin
reactions and is painful to remove. Elderly patients, who comprise by far the
greatest proportion of Foley-catheterized patients, are particularly vulnerable
to tape-related pain and trauma because of their more fragile tissues.

Other securement devices have been developed, but none has
proven adequate and some may themselves be sources of complications. For
example, circumferential leg straps and fasteners can essentially act as
tourniquets that can restrict venous and lymphatic flow. This means that
patients who already suffer from impaired lower-extremity circulation or are at
risk of same will be put at further risk if a leg tourniquet is used on them.
The literature accompanying the Dale strap acknowledges this, warning Not for
use on patients with phlebitis, poor circulation or advanced diabetes.7
Possible complications of constrictive devices such as these include pulmonary
embolism and deep venous thrombosis (DVT).

Among other securement options, some devices employ Velcro
fasteners in combination with a tape base. However, their superiority to simple
adhesive tape has not been proven, and in some areas for instance, adherence
and prevention of catheter movement they appear to offer no real benefit
over tape.

A Reasonable Approach to Preventing CAUTIs

It is true that the literature has yet to point to a clear
protocol for preventing CAUTIs. But that is no reason for inaction. The
prevalence and potential dangers of CAUTIs demand that clinicians and
institutions take certain appropriate steps now, based on current knowledge. It
should be obvious, for example, that because of their complication potential,
urinary catheters should only be used when no other alternative exists, and
should be removed as soon as they are no longer necessary.

Beyond this, urinary catheters should be secured with a
Foley-specific device that has a documented record of successful use. Currently,
the StatLock device fits this description, and others may eventually be proven
effective. Proper securement for infection control appears to be an issue in any
setting where a Foley catheter is used, except where the catheter is used for
simple bladder evacuation during surgery and removed immediately after surgery.
It cannot responsibly be overlooked.

Using StatLock in combination with an anti-infective catheter
such as Bardex I.C. also seems wise in the current environment. Clinicians
should monitor the literature to see if future studies confirm the considerable
promise of these devices. But they should note that in the meantime, there is no
known downside to the above recommendations and tremendous upside if preliminary
results are borne out.


Maureen Carignan RN, is senior marketing director, Canada, at
Venetec International.