Adverse effects caused by polypropylene and polyvinyl feline urinary catheters.

Effects of 3 days of open dwelling urethral catheterization were evaluated in normal male cats. Commercially manufactured polypropylene and polyvinyl feline urinary catheters of sufficient length to permit constant urine drainage were compared. Catheters were similar in length, diameter, and design. Hematuria occurred in 6 of 6 cats with polypropylene catheters and in 4 of 6 cats with polyvinyl catheters. For cats with polypropylene catheters, hematuria began within 24 hours of catheter insertion. Hematuria induced by polypropylene catheters was usually more severe in final urinalyses than that induced by polyvinyl catheters. Catheter-induced bacteriuria was found in 5 of 6 cats with polypropylene catheters and in 3 of 6 cats with polyvinyl catheters. Staphylococci and streptococci were the most common bacterial isolates. Microscopic lesions in urethras and bladders were significantly less severe in cats with polyvinyl catheters than cats with polypropylene catheters. With few exceptions, urethras of cats with polyvinyl catheters were microscopically indistinguishable from urethras of noncatheterized cats. Polypropylene catheters consistently induced urethritis which was most severe in some bacteriuric cats. Severe lesions were found in the bladders of all cats with polypropylene catheters. Bladder lesions were common in cats with polyvinyl catheters, but were usually less severe in cats with polypropylene catheters. There was no apparent relation between bacteriuria and bladder lesions.