Sometimes when it's time to remove a Foley catheter, the balloon won't deflate. This problem occurs more commonly in patients with long-term Foley catheters. Even though we have all seen nursing home patients present with penile bleeding after pulling out their Foley catheter with the balloon still inflated, that is obviously not an option for emergency physicians. The problem is that the recalcitrant balloon is sitting out of reach, deep in the urinary bladder.
The cause of the balloon malfunction can be anywhere along the catheter, but it's usually found in the balloon inflation port, the balloon drainage channel, or the balloon itself. A commonly reported cause of the problem is using saline to expand the balloon. With time, salt crystals from the saline precipitate in the various locations responsible for deflation failure.
A urologist named Frederic Foley, MD, developed his eponymous catheter in the late 1920s and early 1930s. It was originally an open system, but was turned into a closed system with a bag in the 1950s. I suspect that we are pretty much familiar with the catheter parts, which include the balloon inflation port, the urine drainage port, the inflatable balloon to anchor the catheter in the bladder, and the tip or bladder opening.
Catheters can be made of rubber, plastic, or silicone. The balloon volumes range between 5 mL and 30 mL. There are also straight single-use catheters, the curved or coudé catheter, and a three-way Foley catheter for administering medications or irrigation. Catheters come in multiple diameters, and is measured using the French scale or French gauge system. It is usually abbreviated as Fr, but other variations, including CH or Ch for the system's inventor Joseph-Frédéric-Benoît Charrière can be used. The higher the number, the larger the catheter diameter, and 3 Fr is equal to 1 mm. So a 24 Fr catheter measures 8 mm in external diameter. The range of sizes typically available are as follows: 5 Fr, 6 Fr, 8 Fr, 10 Fr, 12 Fr, 14 Fr, 16 Fr, 18 Fr, 20 Fr, 22 Fr, 24 Fr, and 26 Fr.
Managing the Failure to Deflate
Managing a Foley balloon's failure to deflate includes addressing the potential sites of obstruction in either the balloon inflation port, the balloon drainage channel, or the balloon. Consequently, the techniques used involve drainage port and channel management or balloon destruction. A number of different techniques have been reported in the literature, but I will focus on those most practical for emergency physicians. Having an ultrasound machine available to visualize the balloon would be extremely useful with most of the following techniques.
Consider and Manage Balloon Cuffing
The failure to remove a Foley catheter may not be caused by failure of the balloon to deflate. Instead, it can be caused by balloon cuffing, where the balloon deflates but fails to deflate flush with the catheter. Instead, a circumferential elevated cuff persists at the balloon equator and makes catheter removal nearly impossible. This is remedied by placing 0.5 to 1.0 mL of water into the balloon to smooth out the contour of the balloon, allowing subsequent removal.
Removal of the Balloon Inflation Port
The first step in attempting to deflate a Foley balloon is often cutting off the inflation port with a pair of scissors. The balloon will promptly deflate if the obstruction involves a defective inflation port. The water from the balloon will be observed dripping from the inflation port.
Once the inflation port has been removed, the channel is now available for inserting a lubricated guidewire. A guidewire from a central line kit or ureteric guidewire can be used with its floppy end first to try to clear the drainage channel of any debris. If this does not work, the guidewire can be used to puncture the balloon. After instilling 200 mL of water into the bladder, insert the firm end of the guidewire to puncture the balloon. Filling the bladder with water protects it against bladder injury in case the balloon bursts instead of draining slowly.
Balloon Overinflation and Rupture
This technique is generally discouraged because bladder injury can occur and balloon fragments can remain in the bladder requiring removal by cystoscopy. It involves placing an intravenous catheter into the drainage channel of the Foley catheter (after the inflation port removal) and instilling water under pressure. Again, injuries to the bladder have been reported, and unwanted balloon fragments are almost guaranteed.
Direct Puncture of the Balloon
Percutaneous suprapubic puncture of the balloon using ultrasound guidance is another option. The balloon is brought into close contact with the bladder wall, and an ultrasound-guided percutaneous suprapubic puncture is accomplished. Other techniques describe vaginal, transurethral, or transrectal approaches, but these are most likely outside the scope of emergency physicians. Again, any time a balloon puncture technique is accomplished, inspect the balloon after catheter removal to assess for missing fragments. If a portion of the balloon is missing, then a subsequent cystoscopy is recommended.
Chemical Deflation of the Balloon
The use of chemicals such as acetone has been reported, but mineral oil is probably the safest. The technique involves instilling 10 mL of mineral oil into the balloon inflation lumen. If balloon rupture does not occur in 15 minutes, the procedure is repeated. Acetone and mineral oil can take several hours to rupture the balloon. These chemicals can be irritating to the bladder, and a new Foley should be placed after the balloon is deflated to irrigate the bladder to remove them. It is recommended that the bladder be filled to capacity with normal saline before chemical deflation is attempted.
Failure of the Foley balloon to deflate is a relatively rare event, but it can be quite disconcerting when it happens. After watching this month's video and reviewing the options discussed above, you can rest assured that you now have all the tools necessary to successfully resolve this emergency.