What is a Foley Catheter?

Foley catheters are used for continuous drainage of urine and remain inside the bladder for a period of time. They usually have two lumens, or channels: One that drains the urine into a bag, and a smaller one that allows the inflation of a small balloon with sterile water (after insertion) that sits inside the bladder neck and prevents the catheter from falling out. Occasionally, a foley catheter has three lumens, or channels, with the third one being used for bladder irrigation.

On removal of the catheter, the balloon is deflated through its channel and the catheter is then easily removed.

Catheters come in a variety of sizes and are measured using what is called a French Size (FR). This is usually printed on the packaging, as well as on the end of the catheter. Occasionally, depending on the brand, you may see a CH abbreviation. This is short for Joseph Charrière, a 19th century surgical instrument maker, who created the French sizing! The bigger the numeral, the larger the catheter. For example, an 8 FR might be appropriate for a small child, whereas most adults tend to use between 12 FR, 14 FR or a 16 FR. This is typically determined by your healthcare profession or nurse.

If you have any questions about your catheter, or if you are experience any issues, please don’t hesitate to consult your nurse or see a healthcare professional.