Foley Catheter Foley catheters are flexible (usually latex) tubes that are passed through the urethra during urinary catheterization and into the bladder to drain urine. They are retained by means of a balloon at the tip which is inflated with sterile water. The balloons typically come in two different sizes: 5 cc and 30 cc. They are commonly made in silicone rubber or natural rubber.rnrnThe relative size of a Foley catheter is described using French units (F).[1] The most common sizes are 10 F to 28 F. 1 F is equivalent to 0.33 mm = .013? = 1/77? of diameter. Thus the size in French units is roughly equal to the circumference of the catheter in millimetres.rn rnSide view diagram of male urinary tract with Foley catheter in place to drain urine. A balloon near the tip holds the catheter in place.rn rnFoley catheter (F/Ch. 24) positioned in a male; balloon blocked and outlet plug put on.rnrnFoley catheters come in several sub-types. Coudé (French for elbowed) catheters have a 45° bend at the tip to allow easier passage through an enlarged prostate. Council tip catheters have a small hole at the tip which allows them to be passed over a wire. 3-way catheters are used primarily after bladder, prostate cancer or prostate surgery. They have a third arm or bell that allows an irrigant to pass to the tip of the catheter through a small separate channel into the bladder. This serves to wash away blood and small clots through the primary arm that drains into a collection device. This prevents larger clots, which might plug the catheter, from forming. The second, or inflation, arm has a small plastic valve that allows for the introduction or removal of sterile water through a very small channel to inflate or deflate the retaining balloon.rnrnFoley catheters can also be used to “ripen” the cervix, to allow the induction of labour. The catheter is inserted behind the cervical wall and inflated. The remaining length of the catheter is gently pulled and taped to the...