In urology, a Foley catheter is one of many types of urinary catheters (UC). The Foley UC was named after Frederic Foley, who produced the original design in 1929. Foleys are indwelling UC, often referred to as an IDCs (sometimes IDUCs). This differs from in/out catheters (with only a single tube and no valves, designed to go into the bladder, drain it, and come straight back out). The UC is a flexible tube if it is indwelling and stays put, or rigid (glass (very rarely) or rigid plastic(usually)) if it is in/out, that a clinician, or the client themselves, often in the case of in/out UC, passes it through the urethra and into the bladder to drain urine.
Foley and similar brand catheters usually have two separated channels, or lumina (or lumen), running down its length. One lumen, opens at both ends, drains urine into a collection bag. The other has a valve on the outside end and connects to a balloon at the inside tip. The balloon is inflated with sterile water or saline while inside the bladder to prevent it from slipping out. Manufacturers usually produce Foley catheters using silicone or coated natural latex.[citation needed] Coatings include polytetrafluoroethylene, hydrogel, or a silicone elastomer – the different properties of these surface coatings determine whether the catheter is suitable for 28-day or 3-month indwelling duration. A third type of UC has three lumens for using for bladder washouts post prostate surgery: one lumen is for urine flow out, one lumen is for saline flow in (bladder washouts solution), and the third is for the balloon to be inflated.[citation needed]
Indwelling catheters/IDCs should be used only when indicated, as use increases the risk of catheter-associated urinary tract infection (UTI) and other adverse effects.[1] While female sex is generally recognised as a risk factor for UTIs, the differences in biological sex are reduced while carrying catheters.[2]