Percutaneous nephrolithotomy


Percutaneous nephrolithotomy (PCNL) is a surgical procedure to remove stones from the kidney by a small puncture wound (up to about 1 cm) through the skin. It is most suitable to remove stones of more than 2 cm in size. It is usually done under general anesthesia. 


What does PCNL involve?


PCNL is a type of 'keyhole surgery' where the stone in the kidney is broken up under vision using a endoscopic instrument called a nephroscope. The nephroscope gets to the kidney through an incision approximately 1 cm in length.

Fragmentation may be needed to break the stone into small pieces using some type of energy probe (ultrasonic, electrohydraulic or laser). The stone fragments are then extracted with the nephroscope (see diagram below) through the small puncture in the back. PCNL usually also includes cystoscopy at the start of the procedure and x-ray screening. 

Percutaneous nephrolithotomy
Percutaneous nephrolithotomy
26/4/2010 | 4Urology Administrator

What are the alternatives to PCNL?


External shock wave treatment, open surgical removal of stones, observation. 

26/4/2010 | 4Urology Administrator

What will happen before the operation?


 If you are taking Aspirin or Clopidogrel on a regular basis, you must discuss this with your urologist because these drugs can cause increased bleeding after surgery. There may be a balance of risk where stopping them will reduce the chances of bleeding but this can result in increased clotting, which may also carry a risk to your health. This will, therefore, need careful discussion with regard to risks and benefits.

You will usually be admitted on the same day as your surgery. You will normally receive an appointment for pre-assessment, approximately 14 days before your admission, to assess your general fitness, to screen for the carriage of MRSA and to perform some baseline investigations. After admission, you will be seen by members of the medical team which may include the Consultant, Specialist Registrar, House Officer and your named nurse. An X-ray may be taken in advance of surgery to confirm the position of your stone(s).

You will be asked not to eat or drink for 6 hours before surgery and, immediately before the operation, you may be given a pre-medication by the anaesthetist which will make you dry-mouthed and pleasantly sleepy.

If you are admitted on the day before surgery, you will normally be given antibiotics into a vein to prevent any infection at the time surgery.

Please be sure to inform your Urologist in advance of your surgery if you have any of the following:

  • an artificial heart valve
  • a coronary artery stent
  • a heart pacemaker or defibrillator
  • an artificial joint
  • an artificial blood vessel graft
  • a neurosurgical shunt
  • any other implanted foreign body
  • a prescription for Warfarin, Aspirin or Clopidogrel (Plavix®)
  • a previous or current MRSA infection
26/4/2010 | 4Urology Administrator

What happens during the operation?


Normally, a full general anaesthetic will be used and you will be asleep throughout the procedure.

You will usually be given injectable antibiotics before the procedure, after checking for any allergies.

The operation is usually carried out in a single stage. First, a small tube is inserted up the ureter into the kidney by means of a cystoscope passed into the bladder. You are then turned on to your face and a puncture track into the kidney is established, using X-ray guidance. Finally, a nephroscope is passed into the kidney and the stone(s) extracted or disintegrated with ultrasound or other source of energy. A catheter is usually left in the bladder at the end of the procedure together with a drainage tube in the kidney.

It may be necessary to puncture the kidney at more than one site if you have many stones scattered throughout the kidney. 

26/4/2010 | 4Urology Administrator

Video of PCNL


26/4/2010 | 4Urology Administrator

What happens after the operation?


On the day after surgery, a further x-ray is normally performed to assess stone clearance. Occasionally, it may be necessary to perform an X-ray down the kidney drainage tube using contrast medium, this is called a nephrostogram. If the x-ray is satisfactory and the bleeding has settled the tube in your kidney and the bladder catheter will be removed. There is often some leakage from the kidney tube site for 24-48 hours and you will be only discharged once this leakage has resolved.

The average hospital stay is 3-4 days.

26/4/2010 | 4Urology Administrator

What are the complications of this treatment?


All operations have potential complications or side effects.

Common Side-Effects (greater than 1 in 10)

  • Temporary insertion of a bladder catheter and ureteric stent/ kidney tube needing later removal
  • Transient blood in the urine
  • Transient raised temperature

Occasional Side-Effects (between 1 in 10 and 1 in 50)

  • Occasionally more than one puncture site is required
  • No guarantee of removal of all stones & need for further operations
  • Recurrence of new stones
  • Failure to establish access to the kidney resulting in the need for further surgery

Rare Side-Effects (less than 1 in 50)

  • Severe kidney bleeding requiring transfusion, embolisation or at last resort surgical removal of kidney.
  • Damage to lung, bowel, spleen, liver requiring surgical intervention.
  • Kidney damage or infection needing further treatment
  • Over-absorption of irrigating fluids into blood system causing strain on heart function 
26/4/2010 | 4Urology Administrator

When will I get home?


When you get home, you should drink twice as much fluid as you would normally to flush your system through and minimise any bleeding. You should aim to keep your urine permanently colourless to minimise the risk of further stone formation.

It may take at least 2 weeks to recover fully from the operation. You should not expect to return to work within 10 days, especially If your job is physically strenuous.

When you leave hospital, you will be given a “draft” discharge summary of your admission. This holds important information about your inpatient stay and your operation. If, in the first few weeks after your discharge, you need to call your GP for any reason or to attend another hospital, please take this summary with you to allow the doctors to see details of your treatment. This is particularly important if you need to consult another doctor within a few days of your discharge. 

26/4/2010 | 4Urology Administrator

Other important points


If you develop a fever, severe pain on passing urine, inability to pass urine or worsening bleeding, you should contact your GP immediately.

Small stone fragments may also pass down the ureter from the kidney, resulting in renal colic; in this event, you should contact your GP immediately. 

You can prevent further stone recurrence by implementing changes to your diet and fluid intake. If you have not already received a leaflet about this, contact your named nurse, the Specialist Nurse in outpatients, your Consultant or click on link.

26/4/2010 | 4Urology Administrator