Infection Control Today - 08/2003: Technologies

August 1, 2003

Technologies, New Guidelines Work to Reduce
Invasive Device-Related Infections

By Kelli M. Donley

Infections related to invasive devices are
receiving unprecedented attention since the release of a Centers for Disease
Control and Prevention (CDC) guideline that updated the topic.

The Guidelines for the Prevention of
Intravascular Catheter-Related Infections, was prepared by numerous infection
control experts, including CDC director Julie L. Geberding, MD, MPH. The update
highlights five significant methods of reducing such infections:

  • Increased education of those inserting such
    devices
  • Using sterile barrier precautions during
    device insertion
  • Using 2 percent chlorhexidine preparation for
    skin antisepsis before insertion
  • Preventing replacing central venous catheters
    regularly
  • Using catheters impregnated with
    antiseptic/antibiotics1

The guidelines use several methods of
categorizing invasive catheters: by type of occupied vessel (peripheral venous,
central venous, arterial); life span (temporary, short-term, long-term,
permanent); insertion site (subclavian, femoral, internal jugular, peripheral,
peripherally inserted central catheter); type of skin to vessel pathway
(tunneled, nontunneled); physical length (short, long); or special feature
(cuff, antibiotic impregnation). Rates of infection associated with invasive
catheters are divided among these subgroups. However, the research shows more
than 80,000 central venous catheter (CVC)-related infections are reported each
year from American intensive care units alone. The average cost of each
infection varies from $34,000 to $56,000; depending on the research figures
used, these infections incur an annual financial burden of $296 million to $2.3
billion to the American healthcare system.

CVC-related infections reported hospitalwide
total more than 250,000 annually in the United States, costing the healthcare
system an estimated $25,000 per infection. Such high rates of infection and
costs have fueled medical device companies to develop innovative methods of
preventing infections associated with their devices.

Kelly Powers, vice president of research and
development at CR Bard, based in Murray Hill, N.J., says the companys Access
Division specializes in long-term vascular access products.

Long-term vascular access devices are
typically given for chemotherapy treatment, he says. These cancer patients
need long-term infusions of chemotherapeutic drugs. There are four major
categories that these devices fall into.

Implanted ports can be placed and left in place
for several years. In general, those patients either die from their cancer or
they recover and the ports are removed. The next is peripherally inserted
central catheters. Those are called PICC lines and they are long-term central
catheters that are placed in the arm.

Also, there are chronic catheters, placed in the
jugular vein and used primarily for the same thing. The final category of
long-term vascular access is for dialysis used for hemodialysis treatment.

Patricia Johnson, RN, MSN, senior marketing
manager at Arrow Medical, based in Libertyville, Ill., says these devices are
used for a variety of patients.

They are used many times by critically ill
patients, she says. Sometimes these are patients that need total perinatal
nutrition. They cant be fed through their stomach or mouth and they need to
get the proteins, fats and carbohydrates through the veins. If you do that in
the peripheral aspect, through the arm, you can cause a lot of phlebitis or
thrombosis just because of the osmolarity and pH of the medications you are
infusing.

Many times trauma patients, burn patients and
patients with major surgery are candidates for a central venous catheter.

However, Johnson warns, central venous catheters
are not inserted without considerable thought.

These devices remain inserted on average from
5 to 10 days, she says. Most people have an average of 7 days. There are
certainly patients who have them in for 2 to 3 weeks because they are just that
critically ill.

Yet, I think any practitioner today only uses
these catheters as they are needed and tries to get them out as soon as they
possibly can.

She says this rush is due to infections
associated with the devices. The challenge for manufacturers has been developing
infection control technologies that last for the entire use of long-term
catheters.

We know there is an average 5 percent
infection rate associated with central venous catheters, she says. In
1991, we introduced a technology to help decrease the risk of catheter-related
blood stream infections. This included silver sulfadiazine and chlorhexidine
being impregnated onto the external surface of the catheter.

Within the last few years, she says company
officials have also been able to impregnate internal lumens, extension line and
the hub of the catheter with the antimicrobials. Research has shown this
technology is effective for 10 to 14 days. Other studies, Johnson says, report
effectiveness of 45 to 54 days after implantation. Further research is needed.

There are different ways of managing
catheters, the most important focusing on sterile technique when they are being
placed, says Powers. From a technology standpoint, we have a major
research and development focus to develop anti-infective coatings. There is a
lot of science working on this right now, but no one has completely mastered
long-term effectiveness.

Short-term effectiveness has been demonstrated.

Our devices are in there anywhere from 30 days to
24 months. Nothing has shown that you can put on a catheter to prevent infection
(for that long).

The primary technology is antibiotics, but this
is less preferred because of bacterial resistance. Silver ion eluding coatings
are fairly promising, but difficult to control the kinetics to be effective for
very long.


Epidemiology, Pathogenesis of Catheter-Related
Infections

Officials at the CDC have been monitoring the
types of infections reported in the United States since 1970. The National
Nosocomial Infection Surveillance System (NNIS) data shows infections in this
arena have changed in reaction to developing antibacterial resistance patterns.
The following timeline denotes the most prevalent catheter-related infections:

  • 1986-1989: Coagulase-negative staphylococci, Staphylococcus
    aureus
    , Candida
  • 1992-1999: Coagulase-negative staphylococci,
    enterococci, Staphylococcus aureus

CDC researchers highlight in 1999 they received
the first data showing Staphylococcus aureus isolates resistant to
oxacillin and Candida albincans isolates were resistant to fluconazole.
Other Candida strains have since become resistant to itraconazole as
well. Also, ICU-related Enterobacteriaceae infections, Klebsiella
pneumoniae
in particular, have become increasingly resistant to
extended-spectrum cephalosporins and broad spectrum antimicrobial agents.1

Short-term catheter insertion sites primarily
develop infections because of migration of skin organisms near the area. However
long-term catheter sites more frequently cause infections because of hub
contamination.1

We know the pathogenesis of catheter-related
infections is that the longer the catheters are left in place, the more
prominent it becomes as being the source of an infection, says Johnson.

Paul Blackburn, RN, senior product manager of
clinical information at CR Bard, says besides the complex antimicrobial
impregnation technologies, there are simple methods healthcare workers (HCWs)
can use to reduce these infections.

Follow the CDC-recommended guidelines for not
only site preparation, but for insertion of the device, he says. We
recommend that HCWs use Chloraprep as the antimicrobial for the site and then we
recommend that they use full sterile barrier precautions during insertion.

Once insertion is complete and HCWs begin the
care and maintenance regime, again we recommend that they use sterile gloves
when cleaning the site. Also, they should use chlorhexidine gluconate and they
should follow their hospitals policy. Chloraprep is manufactured by Medi-Flex
Inc., based in Overland Park, Kan.

Johnson is not as quick to provide company
infection control recommendations.

A manufacturer is responsible to tell you what
their product does, how it works, limitations as we know it, but to say to
people that you need to use this or that, no, she says. We know there is
more than one way to approach things. As long as they are within practice
guidelines and should be research driven, we dont make such recommendations.
We will certainly refer them to the guidelines we try to help people do
critical thinking. What you tell one group of practitioners depending on their
practices in their hospital is not applicable. Currently, we think Chloraprep is
an excellent skin prep and we have it in many of our kits. But we do have some
kits with betadine.

She says it would be presumptuous for a
manufacturer to tell HCWs how to do their jobs.

There are some people who havent moved from
betadine to Chloraprep yet, she says. Some of that is because of financial
aspects in their hospitals they dont want to incur increased costs. Some
have not made the intellectual leap into chlorhexidine and Chloraprep as a skin
preparation. We cant mandate that. As a manufacturer, we are responsible for
our technology and we follow the latest information, guidelines and standards of
practice concerning catheter-related infections; we do not set those standards.
Practitioners, through their research, set the standards they are expected to
practice.


Guidelines, Recommendations

CDC officials report a variety of quality
measures HCWs should be following to minimize catheter-related infections. Their
initial findings should come as no surprise: the shortage of HCWs and critical
level staffing leads to higher rates of infection. They found specialized IV
teams have shown unequivocal effectiveness in reducing the incidence of
catheterrelated infections and associated complications and costs.1

Recommendations concerning the site of catheter
insertion, type of catheter material, hand hygiene and aseptic technique,
site-dressing regimens, skin antisepsis, securement devices, in-line filters,
and others can be found in detail in the report. Notably, the researchers do
recommend the use of 2 percent aqueous chlorhexidine gluconate instead of the
previously accepted use of povidone iodine for skin preparation.


Additional Invasive Devices

Foley catheter manufacturers are also investing
in antimicrobial impregnation technologies. Anthony Conway, president and CEO of
Rochester Medical, based in Stewartville, Minn., says catheter-associated
urinary tract infections are a proverbial thorn in his companys side.

Yet, they may have found an effective tool to
fight this elusive enemy.

Nitrofurazone has been used for many years,
he says. It is used topically for burn patients, for example, and has been
used in the last three of four wars in the field topically to prevent infection
in wounded soldiers.

With the drugs history on the market, Conway
says its apparent durability led to its selection as companys antimicrobial
of choice for their antiinfective line of Foley catheters.

The reason we selected nitrofurazone is that
it hasnt show resistance, he says. During 50 years of use, there has
been essentially no build up of resistance whatsoever. It is not an antibiotic
it is a chemosynthetic. TI is a chemical. It has multiple kill mechanism and
interferes with not just cell walls but with enzyme production of cells in a
number of other ways. It is thought that the reasons for lack of resistant
buildup are because of this multiple kill mechanism. Also, it is not
systemically absorbed.

Because it isnt absorbed into the system,
Conway says, resistance is also prevented.

The drug is not being exposed to bacteria
through the rest of the body, which would increase chance for resistance, he
says. It seems to be the perfect fit. Many experts feel that urinary tract
infections create the largest reservoir in hospitals of potential bacteria pools
that can help generate resistance. By reducing this pool with a topical
application, we certainly feel that it is a positive advancement.

The company specializes in anti-infective Foley
and intermittent catheters.

The best practice standards for infection control
remain critical: hand hygiene, appropriate personal protective equipment,
protection of the sterile field and HCW education concerning invasive devices
should be of utmost concern. HCWs should also keep their eyes open for more
products, both intravascular catheters and Foley catheters, that feature
antimicrobial technologies.