The duration of placement as a predictor of peripheral and pulmonary arterial catheter infections.

To determine the appropriate time for removal or replacement of peripheral and pulmonary arterial catheters in critically ill cancer patients, we prospectively studied 71 peripheral arterial catheters and 71 pulmonary artery (Swan-Ganz) catheters from 110 consecutive cancer patients. All catheters were cultured semiquantitatively, by the roll-plate culture technique. Of the 71 peripheral arterial catheters, 11 (15%) produced local infections (> or = 15 colonies) and four (5.5%) produced catheter-related septicaemia. Ten of the 11 local infections and all four septicaemias occurred after 4 days of catheter placement (P < 0.05). Likewise, of the 71 Swan-Ganz catheters, 12 (17%) produced local infection and four (5.6%) led to septicaemia. Swan-Ganz catheter-related septicaemia occurred at rates of 2% and 16%, before and after 7 days of catheter placement, respectively (P = 0.056). Duration of placement was a risk factor for the development of catheter infections, independent of the patient's neutropenic status, administration of antibiotics such as vancomycin during catheterization, and the presence of concurrent central venous catheters. Life-table analysis showed that the cumulative risks of developing a catheter infection increased from 7% to 17% after 6 days of peripheral arterial catheter placement and from 9% to 18% after 4 days of placement of the Swan-Ganz catheter. We conclude that in the critically ill cancer patient in our unit, peripheral arterial catheters should be changed to a new site every 4-6 days and pulmonary artery catheters every 4-7 days.