A cystotomy is the operation that opens the bladder and removes stones, and in cats it is usually decided by 3 facts: the stones are too large to pass, they are struvite that did not dissolve on a 4 to 8 week diet trial, or there is an obstruction. The surgery takes 45 to 90 minutes, the stay is 1 to 3 days, and the recovery owners manage is 10 days of restricted movement and changed litter.
When surgery is the right answer
Struvite stones under 5 mm often dissolve on a dissolution diet in 4 to 8 weeks, so most vets try that first in a stable cat that is eating and not blocked. Oxalate stones never dissolve and come out once they cause signs or pass 5 mm. Surgery is also the answer for a stone in the urethra, more than 5 stones, or 2 or more episodes in 12 months.
One number drives the urgency: a male cat whose urethra is blocked is a 24-hour emergency, not a surgical booking. Total obstruction kills by potassium and acid-base collapse, and a cat that strains for 12 hours with no urine needs an emergency visit, not a wait for the next available slot.
The 3 pre-op items
Item 1 is bloodwork: a complete blood count plus a chemistry panel with kidney values, electrolytes and glucose. This is where an older cat's chronic kidney disease (CKD) or a high potassium shows up, and both change the anesthetic plan. Expect 80 to 250 USD.
Item 2 is a urinalysis with a urine culture. The sediment tells you crystal type and the pH tells you whether struvite is plausible; the culture tells you whether infection is present, and infection must be treated before surgery because a contaminated bladder wall re-seeds stones. Expect 60 to 150 USD. Sediment reading is its own skill, and the urinalysis reading guide covers what each crystal shape means.
Item 3 is imaging: 2-view radiographs, or ultrasound if the stones are radiolucent. You need a count and a size, because the incision is planned around the largest stone. Expect 150 to 350 USD, and note the same film is the only way to prove the bladder is empty at the 4 to 6 week recheck.
The timeline
| When | What happens | What you do | Typical cost |
|---|---|---|---|
| Day -7 | Bloodwork, urinalysis, culture, imaging | Bring a fresh urine sample if asked; fast the cat from 10 pm the night before labs | 290-750 USD |
| Day -1 | Pre-op call, consent, estimate | Stop food 8-12 hours before, water 2-4 hours before | 0 USD |
| Day 0 | Surgery, 45-90 minutes; anesthesia 60-120 minutes | Leave a phone number that answers | 800-2,500 USD |
| Day 0-1 | Recovery, urinary catheter for 12-24 hours | Visit if allowed; do not bring food | 0 USD extra |
| Day 1-2 | Discharge with 10 days of restricted activity | Set up a small room, 1 litter box, paper litter | 40-120 USD in meds |
| Day 3 | Phone check: appetite, urine volume, incision | Count urine clumps and report | 0 USD |
| Day 10-14 | Suture or staple removal, incision check | Bring the log of urine and appetite | 30-80 USD |
| Week 4-6 | Repeat imaging to confirm zero stones | Book it at discharge, not later | 150-350 USD |
Day 0: what the anesthetist controls
The cat is pre-medicated, induced, intubated and kept on inhalant gas, with heart rate, blood pressure, oxygen saturation, end-tidal CO2 and temperature logged every 5 minutes. Every drug choice, every dose and the fluid rate are set by the anesthetist from body weight and ASA grade — a 3 kg cat with CKD and a 6 kg cat with a normal panel do not get the same plan. Ask 2 questions at the pre-op call: who monitors during the procedure, and what happens if blood pressure drops below 80 mmHg.
The surgeon opens the bladder over the largest stone, removes every stone with a spoon, flushes, then closes in 2 layers with absorbable suture; a 3 to 6 cm incision is typical for a 4 kg cat. The stones go to a lab, and that result in 7 to 14 days decides the diet for the next year.
The first 24 hours
Expect a wobbly cat, a shaved belly, and pink-tinged urine for 24 to 48 hours. The catheter comes out within 12 to 24 hours, and the first voluntary void decides discharge: a cat that has not urinated 8 hours after removal stays another night. Pain control is multi-modal and set by the veterinarian by weight and by palpation response; add nothing from the human cabinet, since 1 paracetamol tablet is lethal to a cat. Water goes down at once, a small meal 2 to 4 hours after recovery.
The 10 days at home
Confine the cat to 1 small room with no jumping surfaces for 10 days; stairs, sofa backs and window sills are where incisions open. Use paper or non-clumping litter for 10 days and change it daily, because clumping clay in a fresh wound is a common revisit. No bath and no harness for 10 days. Check the incision twice a day for redness spreading past 1 cm, discharge, or a visible gap. Feed 3 to 4 small meals a day for the first 5 days, and refresh the water twice daily: 40 to 60 ml per kg per day is the target, so 2 bowls in different rooms beat 1 bowl next to the food.
The recheck nodes
Three nodes matter. Day 3 is a phone call: appetite, urine volume, an incision photo. Day 10 to 14 is the hands-on check and suture removal. Week 4 to 6 is repeat imaging, and it is not optional: a retained stone grows and the next episode is a blockage. Struvite means 4 to 8 weeks of diet past a clear film; oxalate means the diet is lifelong. If infection was found pre-op, add a urine culture at 10 to 14 days and again at 4 weeks if it is still positive.
Recurrence, and what changes it
Oxalate stones return in roughly 20 to 40 percent of cats within 2 to 3 years, which is why water intake is the one variable an owner controls. The guide to reading a radiograph is worth 10 minutes if you want to see what a stone looks like on film at the recheck, and breed-linked urinary risk is one of the things the breed quiz flags before anyone buys a kitten.
When to call the clinic immediately
Straining with no urine for 6 to 8 hours, vomiting after surgery, a distended abdomen, pale gums, a fever above 39.5 C, or an incision that is wet with blood: call now, day or night. Those 6 signs separate a 1-day stay from a second surgery.
Five things to arrange before discharge
- Book the day 10 to 14 and week 4 to 6 appointments before leaving the building.
- Buy 2 weeks of paper litter and 1 shallow tray for the recovery room.
- Clear a 3 by 3 m room of anything the cat can jump onto.
- Ask for the stone analysis to be sent and the result in writing, and log the daily urine clump count for 10 days.
Terms mentioned in this article
Frequently asked
Can the stones be dissolved instead of removed?
Only struvite can be dissolved, and only when the cat is stable and not blocked; the usual trial is 4 to 8 weeks on a dissolution diet with imaging at the end. Calcium oxalate stones never dissolve, and waiting on them risks a urethral obstruction that is far more dangerous than the surgery.
How long will the cat stay in hospital?
Most cats go home 1 to 3 days after surgery, and the deciding factor is voluntary urination after the catheter comes out. A cat that urinates within 8 hours of removal and eats a small meal usually leaves the next morning; one that does not stays another night.
Is the 4 to 6 week X-ray really necessary?
Yes, because a retained stone is the main reason a cat needs a second surgery within a year. The film also gives you a baseline for the next 12 months, and it is the only objective proof that the bladder is clear rather than merely quiet.
Related guides
- Spay Techniques Compared: Incision, Recovery, 2-Week Check
- Cat Dental Extraction: Films First, 14 Days After
- Enucleation Recovery: First 48 Hours and 3 Care Jobs
- Cat Fracture Repair: 3 Fixation Types and the 6-Week Line
- Wound Closure in Cats: Sutures, Open Healing, or a Flap
- Adopting a Cat After Surgery: 14 Days, 5 Red Lines