Central venous catheter-related infection

Introduction

Central venous catheters (CVCs) account for an estimated 90% of all catheter-related bloodstream infections (CRBSI). The duration of use of CVCs remains controversial and the length of time such devices can safely be left in place has not been fully and objectively addressed in the critically ill ICU patient. As a consequence, scheduled replacement remains widely practiced in many 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. A recent meta-analysis concluded that chlorhexidine-silver sulfadiazine (CSS) CVCs appear to be effective in reducing CRI [1].

Materials and methods

This was a prospective randomized double-blind study performed in the adult multidisciplinary ICU at Johannesburg Hospital between 1996 and 1999. The study entailed comparison of a 14-day placement of standard triple-lumen versus antimicrobial impregnated (CSS) CVCs on the rate of CRI. Our aim was to determine whether we could safely increase the duration of catheter insertion time from our standard practice of 7 days to 14 days, to assess the influence of the antimicrobial impregnated catheter on the incidence of CRI, and to elucidate the epidemiology of CRI. One hundred and eighteen critically ill patients were included in the study.

Results

Sixty-two patients received a standard triple-lumen catheter and 56 patients a CSS impregnated triple-lumen catheter. The study spanned 34,951.5 catheter hours (3.99 catheter years). The mean duration of placement for the full sample of 118 CVCs was 12.3 days (range, 1-14). No statistically significant difference in CRI rates between the two types of catheters could be demonstrated. The most common source of primary CRBSI was skin, followed by hub and infusate. The site of CVC insertion (internal jugular vein versus subclavian vein) and the use of parenteral nutrition were not noted to be risk factors for catheter infection.

Conclusions

In this study, we were unable to demonstrate that the CSS catheter provides any significant benefit over standard catheters, which we feel can safely be left in place for up to 12 days and probably 14 days. The most common source of CRI was the skin. The administration of parenteral nutrition and the site of catheter insertion were not noted to be risk factors for CRI.