FEASIBILITY OF PREVENTING ENCRUSTATION OF URINARY CATHETERS

Colonization of urinary catheters by bacteria which produce urease lea ds to an increase in urine pH, followed by deposition of the minerals struvite and hydroxyapatite. Adhesion of these encrusting deposits can be reduced, but not prevented, by using catheters with a smooth surfa ce finish. Chemical methods for preventing encrustation are not comple tely satisfactory. A better way of preventing encrustation would be to prevent colonization of the catheter by bacteria. This might be achie ved by controlled release of antimicrobial agents directly into the ur ine from the catheter itself. Preliminary experiments have demonstrate d the feasibility of controlled release from solid silicone. However, a simpler approach is diffusion of an antimicrobial agent from a solut ion within the retention balloon of the catheter. Further experiments are required to determine the concentrations required and whether they are achievable in practice.