Here’s a quick case. Patient presents with urinary retention, Foley catheter placed, blood-tinged urine output. Initially the patient experiences great relief but gradually develops suprapubic discomfort again.
Questions:
- What’s inside the bladder?
- What’s the bladder volume?
- How is that catheter working?
- What’s that bright echogenic arc coming of the superficial aspect of the Foley bulb?
Discussion:
The catheter was irrigated, and began to drain normally again after a blood clot was pushed out. The patient felt better, the urine flow cleared, and discharge with a leg bag and close urology follow up was arranged.
- A Foley bulb (bright echogenic circular structure) is visible inside the bladder
- Here’s an easy bladder volume calculation: Length x Width x Height x 0.75. Most machines will calculate volume based on your caliper measurements, but 3/4 of a cuboid isn’t that hard to remember
- Two ways to tell the catheter isn’t working:
- The bladder is pretty full despite a properly placed Foley bulb
- Your clinical acumen. Poor urine output, suprapubic discomfort…
- Grating lobe artifact. Note that the echogenic line is parallel to the curve of the transducer, and extends from a bright reflector out laterally from the main beam. Turning down the gain (especially the fair field gain) might reduce this a bit. Here’s a nice quick artifacts review.
