Dx: No Cauda Equina, OK for Discharge
The ultrasound demonstrates a mildly enlarged prostate gland and a likely insignificant amount of post-void residual urine (see instructions of volume estimate calculations in the section below). The prostate is the gray apple-shaped structure that is measured with electric calipers (A----A and B----B) on the cross sectional image. The bladder is black and though usually shaped like a garden pot or rounded off triangle, is bat-shaped on this cross sectional image due to the intruding prostate gland. On the longitudinal image the bladder is shaped more like a bicycle seat. Not the hyperechoic posterior enhancement far field to the bladder and to a lesser extent posterior to the prostate gland.
Given the relatively small amount of urine in the bladder along with multiple alternative causes for urinary retention, namely the opiates he has been taking and the enlarged prostate gland, your suspicion for cord compression drops.
Moreover, there is now no objective evidence of cauda equina syndrome, and this patient has had multiple prior visits for back pain, including some coupled with a complaint of trouble urinating. Based on all of this you feel comfortable that this particular repeat customer is safe for discharge home without any further testing. You give him appropriate aftercare instructions, return precautions and a referral to a pain specialist and a urologist for further evaluation. He, of course, requests a med refill because he is out of his Vicodin and his Percocet. You tell him you don’t feel comfortable with him getting his prescriptions from the ED for this and that is why you have referred him to a pain specialist. Furthermore, you recommend he avoid using opiates for the next 24 hours to make sure his urinary retention improves.
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