Urinary Catheterization - Catheter Types

Catheter Types

Catheters come in several basic designs:

• A Foley catheter (indwelling urinary catheter) is retained by means of a balloon at the tip that is inflated with sterile water. The balloons typically come in two different sizes: 5 cm3 and 30 cm3. They are commonly made in silicone rubber or natural rubber.
• An intermittent catheter/Robinson catheter is a flexible catheter used for short term drainage of urine. Unlike the Foley catheter, it has no balloon on its tip and therefore cannot stay in place unaided. These can be non-coated or coated (e.g., hydrophilic coated and ready to use).
• A coudé catheter is designed with a curved tip that makes it easier to pass through the curvature of the prostatic urethra.
• A hematuria (or haematuria) catheter is a type of Foley catheter used for Post-TURP hemostasis. This is useful following endoscopic surgical procedures, or in the case of gross hematuria. There are both two-way and three-way hematuria catheters (double and triple lumen).
• An external, Texas, urisheat, or condom catheter is used for incontinent males and carries a lower risk of infection than an indwelling catheter.

Catheter diameters are sized by the French catheter scale (F). The most common sizes are 10 F (3.3mm) to 28 F (9.3mm). The clinician selects a size large enough to allow free flow of urine, and large enough to control leakage of urine around the catheter. A larger size is necessary when the urine is thick, bloody, or contains large amounts of sediment. Larger catheters, however, are more likely to damage the urethra. Some people develop allergies or sensitivities to latex after long-term latex catheter use making it necessary to use silicone or Teflon types. Silver alloy coated urinary catheters may reduce infections.