Notes on Catheters

Saturday, 30 April 2005 12:24


As mentioned above, catheters may be used intermittently or may be permanent, the latter being either urethral or suprapubic. Intermittent catheters may be urethral or condom (the latter fit externally over the penis).

There is approximately a 5% incidence of urinary tract infection associated with indwelling urinary catheters.

Indwelling catheters have been a mainstay of long-term treatment of incontinence but are now recognised as carrying significant risk of recurrent bladder infections and may also damage the urethra.

Antibiotic treatment will only ward off infection completely if the catheter is replaced. Catheter bags are an ideal breeding medium for bacteria.

The accepted medical indications for an indwelling catheter are: when there is an untreatable blockage of urine flow; during acute illness/perioperatively, when fluid balance (intake and output) needs to be accurately determined, or when there are pressure sores exacerbated by urinary incontinence.

If the main problem is inability to empty the bladder rather than incontinence, intermittent catheterisation may be a better choice.

Silver-coated catheters are coming into use, silver being antimicrobial, inhibiting bacterial growth within the catheter itself.

There are 2 main types: silver alloy and silver oxide. Some clinical studies have suggested that overall, rates of bacteriuria (presence of bacteria in the urine) are lower in silver-coated catheters than uncoated.

Other catheters, with antibiotic drugs incorporated onto catheter surfaces by chemical methods, are being trialled. These could potentially help to reduce the incidence of urinary tract infections due to catheters.

The United States Center for Disease Control (CDC) issued guidelines for the prevention of catheter-associated urinary tract infections ([1]).

Their recommendations include:

Category I. Strongly Recommended for Adoption

Category II. Moderately Recommended for Adoption

*refers to cleansing of the tip of the penis and around the foreskin: twice daily cleansing with povidone-iodine solution and daily cleansing with soap and water have been shown in 2 recent studies not to reduce catheter-associated urinary tract infection so is not recommended by the panel.

Category III. Weakly Recommended for Adoption

[1] Available online at