Foley catheter sizing

The most common type of indwelling urine drainage system is the Foley catheter. The modern Foley catheter has two lumen tubes, one for urinary drainage and the other for balloon inflation. You can inflate the balloon with air or sterile water. It is inflated after catheterization to assist in keeping the catheter in place. Silicone rubber or Latex are commonly used in Foley catheters.  Latex is prone to overgrowth and has been linked to urethral irritation.

What is foley catheter sizing:

The French scale is used to size Foley catheters based on outer diameter. 0.33 mm = one French (Fr). The size ranges from 12 Fr (4 mm) to 30 Fr (30 mm) (10 mm). In most adults, size 12 Fr is large enough to remove urinary blockage, though practitioners commonly use size 14 to 16 Fr for first catheterization. For appropriate hematuria or clot drainage, larger diameter catheters may be required. A drainage bag is commonly used with the catheter.

Foley catheter sizing Considerations:

• The use of large-diameter catheters on a regular basis can erode the bladder neck and urethral mucosa.
• Blood clots are most typically treated with larger Fr sizes (20-24 Fr).
• In both adult females and males, the most widely used indwelling transurethral and suprapubic catheters range from 14 to 16Fr.
• Most commercially available insertion kits or trays use a 14 or 16 Fr catheter as usual.
• The catheter size 14 Fr is commonly used, while pediatric catheter sizes of 6-12 Fr are favored for younger children.

Foley catheter sizing & shapes:

• Most urinary catheters have two ports on the distal end. The first is a funnel-shaped drainage channel that allows urine to be effluxes once the catheter is in place, and the second is an inflation/deflation channel that allows water to be infused into the retention balloon. The size of the balloon (5cc or 30cc) and the size of the catheter are normally labelled on the infusion port for the balloon.
• Three-way catheters with a third channel are available to allow for continuous bladder irrigation or medicine instillation. This catheter is typically used after urological surgery or when a bladder or prostate tumor is bleeding, and the bladder requires continuous or intermittent irrigation to eliminate blood clots or debris.