I just read an article about The Simon Foundation for Continence, and their series of conferences called Innovating for Continence: The Engineering Challenge. In 2011 they invite three experts in the fields of infections disease, urinary tract infections and urology – Roger Feneley, Calvin Kunin and David Stickler to speak at the conference. The theme was that indwelling Foley catheters are simply too risky to be so commonly used, due to high rates of mortality and other costs to the health care system.
They said that the design of a Foley catheter “violated the integrity of the sophisticated defense mechanisms that protect the bladder from bacterial infection” when used for long-term catheterization.
A Foley catheter is the type with a balloon close the the tip of the end that sits in your bladder. After catheter insertion, the person inserting it inflates the little balloon with saline so that it will not pull through your urethra (or abdominal wall opening in the case of a suprapubic catheter). See picture on the left. When inserted through the urethra, by far the most common method, the balloon sits just on top of the bladder opening with the tip, which has holes for draining the urine, sticking out of the top of the balloon.
The primary focus of concern for the three researchers is that with a Foley catheter in place, the bladder cannot fully drain because the holes that drain the urine are too high in the bladder, on top of the balloon. See picture on the right. This means that there will always be urine in the bladder at the level of the balloon and below. The cycle of filling and refilling in the bladder is crucial for the defense against bacterial infection.
On top of that (no pun intended), the tip of the the Foley catheter can damage the lining of the bladder, further increasing the risk of infection. This may be more common with suprapubic catheters, because they are inserted through the abdominal wall (see pic on left). In that case, the balloon can sometimes fall away from the opening, allowing the tip (lumen) to occasionally dig into the bladder wall. The video below shows some pretty amazing shots of this happening, among other problems associated with the SP Foley catheter.
The call to action espoused by all three experts here is for medical device manufacturers to create an up-to-date device that can avoid the problems associated with Foley catheters, which have been around and used virtually unchanged since Dr. Foley’s invention in 1937. Technology in medical implants, as well as across the board, has advanced considerably since 1937, so surely there must be a better way to perform the simple task of draining urine from the bladder.
See the video below: