Clinical study of the Erlanger silver catheter--data management and biometry

A new scoring system for the clinical diagnosis of catheter-related infections

It is difficult to make the clinical diagnosis of catheter-related infections using the available and established definitions of the HICPAC (Hospital Infection Control Practices Advisory Committee) of the CDC (Centers for Disease Control, definitions of nosocomial infections). The scoring system shown here is a modification of these definitions and has enabled the causal relationship between the catheter and clinical episodes of systemic infections to be quantitatively graded. The scoring system included the following criteria: height and rate of rise of body temperature, attendant shivering, identification of pathogens in blood and/or catheter tip cultures, improvement in the clinical course after catheter removal, signs of catheter exit site inflammation and results of diagnostic tests for other possible sources of infection. These criteria were graded using points and weighted according to their specificity. The comparative evaluation of 65 episodes of systemic infections using the scoring system and the diagnostic criteria of HICPAC showed agreement in 85%. No case was graded "false-negative." In nine of ten false-positive cases additional findings supported the presence of a catheter-associated infection. This scoring system appears, therefore, to be more sensitive than existing diagnostic criteria, without loss of specificity.

Reduced rates of catheter-associated infection by use of a new silver-impregnated central venous catheter

A central venous catheter with a new form of silver impregnation of the internal and external surfaces was investigated for antimicrobial activity and tolerance in patients in a controlled comparative, prospective and randomized clinical study. Commercially available catheters with no antimicrobial activity were used as controls. One hundred sixty-five catheters were included in the final evaluation. All catheters were percutaneously inserted for the first time with a duration of > or = 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 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.