An in vitro model for studying the effect of the subcutaneous tunnel and the skin exit site on the accuracy of central venous catheter tip cultures.
The diagnosis of central venous catheter-related sepsis depends on a positive culture obtained from the distal intravascular portion of the catheter. The effects of the subcutaneous tunnel and the skin exit site on the accuracy of cultures obtained from the catheter are unknown. We have developed an in vitro model to study the effect of these variables. By inoculating polyethylene catheters embedded in agar with Pseudomonas aeruginosa, we were able to show that: (1) capillary action occurs along catheters in an agar tunnel, (2) organisms that are growing on the distal segment (tip) of the catheter can be dislodged from the surface of the catheter when it is pulled through the agar tunnel, and (3) pulling a catheter through a contaminated area results in distal contamination.
Harris
G J
GJ
Department of Surgery, University of Iowa Hospitals and Clinics, Iowa City 52242-1086.
Rosenquist
M D
MD
Kealey
G P
GP
D000362:Agar; D000818:Animals; D002405:Catheterization, Central Venous / Q000009:adverse effects*; D002408:Catheters, Indwelling / Q000009:adverse effects*; D004285:Dogs; D066298:In Vitro Techniques; D011095:Polyethylenes; D011552:Pseudomonas Infections / Q000175:diagnosis / Q000209:etiology*; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification*; D017192:Skin Diseases, Bacterial / Q000175:diagnosis / Q000209:etiology*
D011095:Polyethylenes; D000362:Agar