Most infections of this type are caused by gram-positive cocci, in particular staphylococci. Appropriately, most recent clinical investigations aimed at reducing the risk of IV-related infection are centered on reducing colonization of the catheter or surrounding skin by these organisms. 1 Bacteremia caused by the infusion of contaminated fluids is less common, but nevertheless is a potentially serious problem that can affect single patients or dozens of patients, depending on the circumstances of contamination. Staphylococci can, however, multiply in blood products and lipid emulsions. Contamination of the infusate can occur through several routes.
Intrinsic contamination occurs at the time of manufacture of the fluid.
This type of contamination fortunately is rare, but has the potential to cause a large number of episodes of infection. The outbreak was terminated by discontinuing use of the implicated product. More common, and perhaps more insidious, is extrinsic contamination, which occurs during subsequent admixture of IV fluids or during manipulation of the infusion apparatus. Breaks in sterile technique can introduce organisms into the infusate, where they may multiply to high concentrations. Repeated manipulation of infusion sets is a potential means of introduction of bacteria into IV fluids.