Intravascular Catheter-Related infections

Central venous catheter (CVC) use is primarily directed to secure a vascular access for fluids, medications, blood products, total parenteral nutrition (TPN), and hemodialysis. Their use is not limited only to inpatients but also to the outpatient settings. The national nosocomial infection surveillance system reported that the rate of catheter-related bloodstream infection (CRBSI) ranges from 2.1 to 30.2 BSIs per 1000 vascular catheter days. More than 80 000 CRBSIs are estimated to occur annually in the intensive care units (ICUs) in the United States with an attributable mortality ranging from 12% to 25%. In the initially ill patient, the direct implication of CRBSI is an extension of hospital stay by an average of 6 to 7 days; the added cost ranges from $28 690 to $56 167 per each individual episode in ICU patients. PATHOGENESIS Colonization is universal after insertion of a CVC, can occur as early as 1 day after insertion, and is quantitatively independent of a catheter-related infection. Electron microscopy studies of catheter surfaces show that adherent microorganisms can be found in either a free floating form or sessile form embedded in a biofilm. The dynamic process of adherence is the result of the interaction of three factors: the intrinsic properties of the catheter, microbial factors, and host-derived proteins. The physical characteristics of the catheter, such as surface irregularities and charge difference, facilitate bacterial adherence.