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| Surface-modified catheters |
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| Both the internal and external catheter surfaces offer an ideal basis
for the colonization of pathogenic bacteria. Modified catheters have been
on the market for many years that release silver, drugs or disinfecting
agents in an untargeted way to kill the bacteria in the ambient surroundings
of the catheter. A newly developed plastic surface, which kills bacteria
on contact, represents a novel and very promising approach to effectively
tackling the problem of catheter associated infection.
Protection against extraluminal colonization
Researchers have been trying for some 20 years to interrupt the first
step in the pathogenesis of infection, namely bacterial colonization on
the plastic surface, by means of chemical impregnation of the surface ( Bayston,
Milner). These technical improvements are designed to
protect the external surface of the catheter. The aim is to prevent bacteria
from adhering and settling on the external surface of the catheter during
placement or at a later time. It has not become known until recently that
the luminal route of colonization is an equally major source of infection,
particularly in patients receiving complex infusion therapies. Current
evidence suggests that protection of the external surface of the catheter
alone is both inadequate and ineffective.
Preventing migration on external surface
Dressings containing the antiseptically active compounds chlorhexidine
or cuffs on tunneled catheters containing silver compounds have been developed
to prevent bacteria on the skin from migrating along the external surface
of the catheter and entering the blood stream. Both types of devices can
at best only block the infection pathway at the skin and the external
surface of the catheter. Clinical studies have not been able to demonstrate
any significant impact on infection rates by this method (Garland,
et al., Groeger,
et al. ). Catheters which only possess a coating on
the external surface, antiseptic impregnated dressings, or silver cuffs
must be classified as unsuitable to reduce infection rates. |
| This newly developed catheter can be considered the
first representative of a new generation of catheters with antibacterial
efficacy. The new catheter type is associated with significantly lower
risk during use since there is no release of active compounds. The protection
it offers has no impact whatsoever on the medical therapy and remains effective
over long periods of time.
The invention of antimicrobial catheters stems from the desire of physicians
to minimize as much as possible the adverse effects associated with the
increasingly technological degree of medical science. The advantages gained
by the use of an invasive product that enables quick and targeted infusion
therapy come at a cost, because the skin, the natural frontline barrier
between the body's interior and the outside environment, between the circulatory
system and exogenous germs, has to be penetrated. The associated danger
of bacterial colonization can be effectively eliminated by intelligent
modification of the catheter surface with a bacteria-repellent coating
– exactly what B. Braun accomplished with their antimicrobial catheter
Certofix® protect. |
| 100% efficacy and the fullest benefit can be derived
from an antimicrobial catheter when it is used in conjunction with the
hygiene recommendations. The disinfection of the patient and medical staff
plays a particularly important role, as a recently published study conducted
at a university hospital has confirmed (Jeske,
et al.). The authors tested puncture needle, dilatator
and guidewire for microbes and compared the microbiological findings with
those found on the catheter tip right after the catheter was removed. In
five out of seven catheters that had to be removed due to a catheter associated
infection, the bacterial strains identified were the same as on the catheter
tip and the puncture instruments. This suggests that the bacteria that
were later localized on the catheter surface and caused the clinical symptoms
of infection had already been introduced at the time of puncture. Observance
of the hygiene recommendations and the use of an antimicrobial catheter
can effectively break the chain of bacterial migration. The antibacterial
surface of Certofix® protect acts like a second defensive barrier that
shields the catheter surface from any germs that may have penetrated the
frontline. The combination of both measures, hygiene and antibacterial
catheters, affords maximum protection. Obviously, nobody wants a patient
undergoing a routine surgical intervention to end up in the intensive care
unit with a bacteremia or even sepsis. |
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| Efficacy of the antibacterial surface maintained after
over a 30 days period |
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