The lumen size of a urinary catheter is expressed in what unit?

The lumen size of a urinary catheter is expressed in French, which is a unit of measurement that denotes the diameter of the catheter. One French unit corresponds to 0.33 millimeters in diameter. This system allows medical professionals to quickly understand the size of the catheter they are working with, as it directly relates to its capacity to allow urine drainage or the ease of insertion.

The French scale is widely used in urology and a variety of other medical specialties that involve catheterization, as it provides a standardized way to communicate catheter sizes effectively. While other units like milliliters and cubic centimeters relate to volume, and gauge is commonly used for needles, they do not describe the diameter of lumens in catheters. Thus, using the French scale is both practical and essential in clinical practice for urinary catheterization.