Most small kidney stones pass on their own or are treated with shockwave lithotripsy or ureteroscopy. Large or complex stones often need a more direct route into the kidney. Based on NHS, NICE, EAU, AUA and NIDDK information, this guide explains what PCNL involves, how to prepare, what recovery looks like and which warning signs need urgent attention.
Medically reviewed by Prof. Dr. Samir Ahmed Al-Samarrai, consultant urologist. Last reviewed: · Last updated:
What is PCNL and what is mini-PCNL?
“Percutaneous” means through the skin and “nephrolithotomy” means taking stones out of the kidney. The surgeon makes a small puncture in the back, widens it into a narrow tract and passes a telescope (nephroscope) into the kidney. The stone is broken up with a laser, ultrasound or mechanical device and the fragments are removed. The Royal Wolverhampton NHS leaflet notes that PCNL has largely replaced open surgery for stones because clearance is similar and recovery is faster.
Mini-PCNL uses smaller instruments and a narrower tract. According to the EAU guidelines, reviews linked it with less blood loss, fewer transfusions and a shorter hospital stay than standard PCNL, with similar stone clearance.
Which kidney stones is PCNL used for?
Stone size and position guide the choice of treatment (see kidney stone size):
- According to NICE, adults with kidney stones over 20 mm, including staghorn stones, should be offered PCNL.
- According to the EAU guidelines, PCNL is the first-line treatment for kidney stones larger than 2 cm.
- According to the AUA, people with symptoms and a total kidney stone burden over 20 mm should be offered PCNL first, not shockwave lithotripsy.
- For lower-pole stones, the EAU suggests PCNL or ureteroscopy even for stones over 1 cm.
- PCNL may also be used when other treatments have failed or are not possible.
For all options, see our guide to kidney stone treatment.
Assessment (diagnosis) and preparation
The AUA recommends a non-contrast CT scan before PCNL to map the stones, a urine test before any stone procedure, and a urine culture if there are signs of infection. Imaging also shows nearby organs so the puncture can be planned safely. The EAU lists reasons not to proceed, including an untreated urinary infection, a tumour in the access route, a possible kidney cancer and pregnancy.
- Tell the team about all your medicines, especially blood thinners; the EAU notes these are usually paused before PCNL, but any change is decided by your doctors.
- Mention implanted devices, previous resistant infections and allergies.
- Follow the anaesthetist’s fasting instructions; stopping smoking lowers the risk of complications.
- Compression stockings or a blood-thinning injection may be used to reduce clots.
How PCNL is done
- You receive a general anaesthetic and antibiotics.
- A thin tube is often passed up the ureter so dye can outline the kidney.
- You lie face down or on your back; the EAU states both positions are equally effective.
- Guided by X-ray or ultrasound, a needle enters the kidney and the track is widened.
- The stone is broken up and removed, and a drain or stent may be placed.
According to the Royal Wolverhampton NHS leaflet, the operation usually takes 1 to 3 hours.
Nephrostomy tube, stent, hospital stay and recovery
You may wake with a nephrostomy tube (a drain from the kidney through the back), a ureteral stent, a bladder catheter, or a combination. In selected uncomplicated cases the tube can be left out (“tubeless” PCNL), which the EAU links with less pain and a shorter stay.
According to the Liverpool University Hospitals leaflet, the wound is about one centimetre, the nephrostomy and catheter are usually removed one to two days after surgery, and a stent is usually removed after two to four weeks. The Royal Wolverhampton leaflet says most people stay one to three days (the Liverpool leaflet says about three or four days) and full recovery takes two to four weeks. Blood in the urine is common at first. Drink plenty, avoid heavy lifting, and ask when to drive and return to work.
Possible risks and complications
According to the EAU guidelines, a review of almost 12,000 patients reported fever in 10.8%, blood transfusion in 7%, chest complications in 1.5%, sepsis in 0.5%, injury to nearby organs in 0.4%, embolisation to stop bleeding in 0.4% and death in 0.05%. The Royal Wolverhampton NHS leaflet estimates:
- Urine infection needing antibiotics: between 1 in 2 and 1 in 10 patients.
- Remaining stones needing further treatment: between 1 in 5 and 1 in 20.
- Sepsis (serious infection) needing an unexpected intensive care admission: between 1 in 10 and 1 in 100.
- Bleeding needing embolisation: between 1 in 50 and 1 in 100.
- New stones within 5 to 10 years: about 1 in 2, so prevention advice matters.
PCNL compared with ureteroscopy and shockwave lithotripsy
Stone sizes below follow NICE for adults with kidney stones; hospital stay follows NIDDK. Read more about flexible ureteroscopy and shockwave lithotripsy.
| Feature | PCNL | Ureteroscopy | Shockwave lithotripsy |
|---|---|---|---|
| Route | Small puncture in the back | Scope through the urinary passage, no cut | Shock waves from outside the body |
| Kidney stones (NICE, adults) | Offered over 20 mm, including staghorn | Considered 10-20 mm, or larger if PCNL is not an option | Offered under 10 mm; considered 10-20 mm |
| Hospital stay (NIDDK) | May be several days | Usually home the same day | Outpatient |
| Trade-off | Clears large stones; more invasive | No wound; a stent may be left | Non-invasive; fragments must pass |
When to seek urgent care after PCNL
Contact your urology team straight away, or go to the nearest emergency department if you feel seriously unwell, if you have:
- Fever, shivering or feeling very unwell.
- Increasing pain in the kidney area.
- Severe pain when passing urine, or being unable to pass urine.
- Heavy or worsening bleeding.
Frequently asked questions
Is PCNL a major operation?
Yes. NHS leaflets describe PCNL as a major keyhole procedure carried out under general anaesthetic, usually with a short hospital stay. It is generally kept for larger or complex kidney stones, where the guidelines consider its higher clearance worth the additional risks compared with less invasive treatments.
What is the difference between PCNL and mini-PCNL?
Mini-PCNL uses smaller instruments and a narrower track into the kidney. According to the EAU guidelines, reviews showed less blood loss, fewer transfusions and a shorter stay than standard PCNL, with similar stone clearance. The surgeon chooses the approach based on stone size, position and kidney anatomy.
Will I wake up with a tube in my back?
Possibly. Many patients have a nephrostomy tube, a ureteral stent, a bladder catheter or a combination. In selected uncomplicated cases the tube may be left out, which is called tubeless PCNL. Your surgeon will explain what to expect and when each tube is likely to be removed.
How long does recovery take?
According to the Royal Wolverhampton NHS leaflet, most people stay in hospital for one to three days and full recovery takes two to four weeks. Blood in the urine is common at first. Avoid heavy lifting for several weeks and ask your surgeon when to return to work and driving.
Can kidney stones come back after PCNL?
Yes. The Royal Wolverhampton NHS leaflet estimates that about 1 in 2 people form new stones within 5 to 10 years. Stone analysis, blood and urine tests, good fluid intake and dietary advice from your doctor help lower the chance of stones returning.
Is PCNL suitable for everyone?
No. The EAU lists untreated urinary infection, pregnancy and a tumour in the access route among reasons not to proceed, and blood thinners usually need to be paused under medical supervision. Your urologist weighs your general health, stone and kidney anatomy before recommending PCNL or another option.
Sources
- Renal and ureteric stones: assessment and management (NICE guideline NG118)
- EAU Guidelines on Urolithiasis
- Kidney Stones: Surgical Management Guideline (AUA/Endourological Society)
- Treatment for Kidney Stones (NIDDK)
- Percutaneous Nephrolithotomy (keyhole surgery for kidney stones) – The Royal Wolverhampton NHS Trust
- Percutaneous nephrolithotomy (PCNL) – Liverpool University Hospitals NHS Foundation Trust
Book a consultation
Prof. Samir Al-Samarrai and Dr. Amer Mousa assess urological conditions at Prof. Al-Samarrai Medical Center, Dubai Healthcare City, and discuss the options that suit your case. Medical consultations are confidential.
Read more: Urologist in Dubai: doctors, services, insurance and booking
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