Central Venous Catheter-Related Infection

Intravascular devices are an integral component of modern-day medical practice. Infection is one of the leading complications of intravascular catheters and is associated with an increased mortality, prolonged hospitalization and increased medical costs. Central venous catheters (CVCs) account for an estimated 90% of all catheter-related bloodstream infections (CRBSI). A host of risk factors for CVC-related infections have been documented. This includes most importantly, duration of catheterization. The duration of use of CVCs remains controversial and the length of time such devices can safely be left in situ has not been fully and objectively addressed in the critically ill patient. As a consequence, scheduled replacement remains widely practiced in many Intensive Care Units(ICUs). Over the past few years, antimicrobial impregnated catheters have been introduced in an attempt to limit catheter-related infection (CRI) and increase the time that CVCs can safely be left in place. Recent meta-analyses concluded that antimicrobial impregnated CVCs appear to be effective in reducing CRI. The topic however, remains extremely controversial with different viewpoints appearing in the literature recently.

This was a prospective randomized double-blind study performed in the multidisciplinary ICU at Johannesburg Hospital over a four year period.The study entailed a comparison of standard triple-lumen versus antimicrobial impregnated CVCs on the rate of CRI. The aim was to determine whether the researchers could safely increase the duration of catheter insertion time from the standard practice of seven days to 14 days, to assess the influence of the antimicrobial impregnated catheter on the incidence of CRI, evaluate risk factors and elucidate the epidemiology of CRI.

Intravascular devices are an integral component of modern-day medical practice. They are used to administer intravenous fluids, medications, blood products and parenteral nutrition. In addition, they serve as a valuable monitor of the hemodynamic status of critically ill patients.

Infection is one of the leading complications of intravascular catheters and is associated with an increased mortality, prolonged hospitalization and increased medical costs. Central venous catheters(CVCs) account for an estimated 90% of all catheter-related bloodstream infections(CRBSI). A host of risk factors for CVC-related infections have been documented. This includes, most importantly, the duration of catheterization. The duration of use of CVCs remains controversial and the length of time such devices can safely be left in situ has not been fully and objectively addressed in the critically ill patient. As a consequence, scheduled replacement remains widely practiced in many Intensive Care Units(ICUs),the mean time in a recent study in mainland Britain, being 6.5 days.Over the past few years, antimicrobial impregnated catheters have been introduced in an attempt to limit catheter-related infection(CRI) and increase the time that CVCs can safely be left in place.Recent meta-analyses concluded that antimicrobial-impregnated CVCs appear to be effective in reducing CRI.The topic remains extremely controversial with differing viewpoints appearing in the literature.

This was a prospective randomized double-blind study performed in the multidisciplinary ICU at Johannesburg Hospital, Johannesburg, South Africa over a four year period. The study included 118 critically ill patients and entailed comparison of a 14-day placement of a standard triple-lumen central venous catheter (ARROW Standard Triple Lumen Catheter, Arrow International Inc., Reading, PA, US) versus an antimicrobial impregnated catheter (chlorhexidine-silver sulfadiazine)(ARROWgard Triple Lumen Catheter, Arrow International Inc.,Reading, PA, US) on the rate of CRI.

The aim was to:

1. Determine whether the duration of catheter insertion time could safely be increased from our standard practice of seven days to fourteen days
2. To assess the influence of the antimicrobial impregnated catheter on the incidence of CRI
3. To evaluate other previously recorded risk factors for CRI, as well as to
4. Elucidate the epidemiology of CRI.

The randomization protocol involved equal numbers of the two types of non-distinguishable catheters being mixed in consignments and then selected in a consecutive fashion for placement in study candidates.

Consent was obtained prior to enrollment in the study. Standard infection control measures were practiced with catheter insertion.

Skin swabs were taken for culture prior to cleansing with a chlorhexidine containing solution and subsequent catheter insertion. Catheters were inspected and dressed daily, and studied for colonization and CRBSI at removal. The origin of each CRBSI was sought by culturing all potential sources (skin, catheter segments, hubs and infusates). A semiquantitative culture of the catheters using the roll-plate technique was performed and DNA-molecular typing employed to assist in microbiological analyses. All relevant clinical data was collected and evaluated.

CRI was defined according to the criteria proposed by the Centers for Disease Control and Prevention in the USA.

The study was approved by the Committee for Research on Human Subjects of the University of the Witwatersrand.

Eligibility Criteria:
Inclusion Criteria:

* critically ill patients likely to require central venous catheter for at least 14 days
* age 18+ years
* white cell count on admission \> 4 x 10 to 9/L
* absence of skin burns
* no history of allergy to sulfa containing preparations
* consent obtained
* catheter to be inserted via internal jugular or subclavian veins

Exclusion Criteria:

* age \< 18 years
* white blood cell count on admission of less than 4 x 10 to 9/L
* skin burns
* history of allergy to sulfa-containing preparations
* guidewire changes