Even though the tubing may be placed in the correct location, at times urine may not flow. There are several potential issues leading to this situation:

Occasionally a catheter can be placed in the right location but can kink, leading to a lack of urine output. This can occur when the catheter is undersized since smaller Foleys are more flexible. If this occurs, you must remove the catheter and re-place it.

If the drainage bag is above the patient's bladder or is too full, no urine will flow into the bag. The bag must simply be moved downward to harness gravity's force or must be emptied, respectively.

The catheter may be blocked with blood clots. If the patient is having urologic bleeding, stagnant blood can clot and obstruct the catheter such that no urine flows out. Large clots have to be manually removed. In order to keep the system open, you may need to switch to a three-way catheter, and allow normal saline to flow into the catheter's inlet so that the bladder can be "washed" out.

Xylocaine jelly may be occluding the tubing. Usually the jelly will dissolve in a few seconds. If it does not you will need to manually irrigate the jelly until urine flows.