A central,venous catheter with a new form of silver impregnation of the internal and external surfaces nas investigated for antimicrobial activity, and tolerance in patients in a controlled comparative, prospective and randomized clinical stud,); Commercially available catheters with no antimicrobial activity,itg were used as controls. One hundred sixty-five catheters ere included in the final evaluation,. II catheters n.ere percutancously inserted for the first time with a duration of greater than or equal to 5 days and a microbiological examination of the catheter tip, Catheter location (> 90% internal jugular, vein), mean duration of catheterization (8-9 days), patients' age and diagnosis were comparable in both groups. Silver, impregnated catheter tips showed an incidence of colonization in 1 14.2/1000 catheter days and control catheters in 22.8/1000 catheter days. This represents a reduction of 37.7%, Catheter-associated infections were diagnosed in the silver group in 5.26/1000 catheter days and 18.34/1000 catheter days in the control group, indicating a reduction rate of 71.3% (P<0.05, chi(2)-test). No complications or side effects were documented in either group.