Voiding urohydropropulsion in the female cat: technique
8-year-old spayed female cat with recurrent cystitis. Radiographs show four radiopaque cystoliths of 1–2 mm, compatible with calcium oxalate, in an otherwise normal bladder.
How is voiding urohydropropulsion correctly performed?
chevron_right Show answer and explanation
A. With the cat awake in lateral recumbency, pressing the bladder as soon as it feels full
Without anaesthesia the urethra does not relax and the procedure is painful; in lateral recumbency the uroliths do not settle at the bladder neck.
B. It can be used for uroliths of any size, because the urethra dilates
It only works if the uroliths are smaller than the distended urethral lumen; larger ones can become lodged in the urethra.
C. Under anaesthesia, distend the bladder with sterile saline via a catheter, hold the cat with the spine vertical, agitate the bladder and express it with gentle sustained pressure
Correct. Gravity brings the uroliths to the bladder neck and forced voiding with a relaxed urethra flushes them out. Repeat until no more emerge and confirm by radiograph that none remain.
D. It is preferable to medical dissolution also for sterile struvite
Sterile struvite in cats dissolves well with diet; the consensus prioritises dissolution of dissolvable uroliths.
lightbulb Key takeaway
Urohydropropulsion is simple, inexpensive and avoids cystotomy for small uroliths, especially in females. Mild transient haematuria is common; do not overdistend an inflamed bladder.
References: Lulich JP et al. ACVIM Small Animal Consensus Recommendations on the Treatment and Prevention of Uroliths in Dogs and Cats (2016)
Test yourself with 10 random questions
Urinary system · 100 questions, a different test every time
Related questions
Updated: October 31, 2026 · Educational content for veterinary professionals. It does not replace current clinical guidelines or the judgement of the attending veterinarian.