When is a triple-lumen catheter used?

• A. Used for measuring bladder pressure only
• B. Used for urine drainage only
• C. Used for catheter irrigation only
• D. Used when a patient requires intermittent or continuous bladder irrigation; third lumen is used

Answer: (D)

A triple-lumen catheter has an extra channel beyond the two in a standard Foley, so you can irrigate the bladder while urine continues to drain. The third lumen is dedicated to delivering irrigation fluid into the bladder, allowing intermittent or continuous bladder irrigation (CBI) without interrupting drainage. This setup is especially useful after urologic procedures or when there's bleeding or clot risk, as irrigation helps keep the catheter patent by flushing out blood and clots. The balloon-tube channel to hold the catheter in place remains, so you can maintain retention while both irrigation and drainage occur.

The other options don’t capture this combination: measuring bladder pressure isn’t the primary reason for a third lumen, and a two-lumen catheter already handles drainage; using a catheter for irrigation alone doesn’t explain the need for a third lumen alongside drainage.