In part 3 of our discussion about the uses of bladder ultrasound in the emergency department, we consider the case of a 70 year-old man with urinary retention in whom we were unable to place a urinary catheter.

Case 4

When we encounter this situation, the obstruction is usually either a big prostate gland or a stricture. If you have a urologist available, they often do a dilation either at the bedside or in the operating room. However, what if you don’t have a urologist available? These patients are miserable. You can transfer them to a urologist, but there is going to be time passing while they get to the receiving facility, and even once they arrive it’s going to take time to get the procedure done.

Other than learning to do the urethral dilation, is there anything you can do to give this patient some relief? How about aspirating the urine out of the bladder? That wouldn’t fix the problem, but it would provide relief while you are finding a specialist that can provide definitive care.

This procedure is described in the text books, but usually in the setting of getting a sterile urine sample from an infant. It is well documented that it can be safely done, particularly if guided by ultrasound. We used a spinal needle, extension tubing, a three way stop cock and 50 ml syringe. One operator held the needle in place with ultrasound guidance while the other aspirated 50 ml at a time.

The video below shows the “before” image, which clearly demonstrates a distended bladder and an enlarged prostate gland. That clip is a short axis (axial) view of the bladder. (I can’t say definitively whether the obstruction was the prostate or a stricture, but it had to be emptied regardless.) After that, it shows the images obtained during the aspiration (mercifully in fast forward).

We didn’t necessarily have to get the bladder as completely empty as we did, but since it was was going well we got all the urine out that we could. We did change from short axis to long (“out of plane” to “in plane” in terms of the needle) near the end of the procedure to keep a better view of the entire needle once the volume of the bladder started to get small.

This procedure may seem daunting, but if you are comfortable with the anatomy and ultrasound guided needle placement, it is within a skill set that you already have.

Let’s summarize the three bladder ultrasound posts

In the first post we saw a patient, case one, with a catheter that wasn’t draining. The ultrasound instantly showed malposition (as opposed to obstruction) and allowed the proper steps to be taken.

The second post had two patients with something in the bladder. Case two presented with urinary hesitancy and likely would have been treated as BPH without the images that changed the working diagnosis. Case three was another catheter that was not draining. In this case, unlike case one, we found that the problem was clotted blood in the bladder rather than a malpositioned catheter.

In this post, we see how bladder ultrasound can be used to guide a suprapubic aspiration. Admittedly, it’s not curative, but the patient certainly felt better while definitive care was arranged.

Bladder ultrasound is not as heroic as some other applications of point-of-care ultrasound, but it can be a very helpful tool in scenarios like these.