Percutaneous nephrolithotomy (PCNL)

Using X-ray guidance, a urologist passes a surgical telescope (nephroscope) through a small cut in the skin into the kidney to see your stone. The stone is broken into fragments and removed via the nephroscope.

A drain called a nephrostomy tube may be left in the kidney. A fine tube or stent that goes from the kidney down the ureter and into the bladder may also be inserted. The fluid that comes out is initially blood stained but clears in one to two days. A urinary catheter is inserted after the operation.

The treatment takes one to two hours and is carried out under general anaesthetic.

You'll need to attend a pre-op assessment to ensure that you are fit enough to undergo surgery. Bring a list of your regular medications with you. You may have blood tests as well as other investigations such as a urine test, electrocardiogram (ECG) or chest X-ray prior to this appointment.

If you take blood thinning medication, these will need to be stopped in advance. Your doctor will advise you about this.

If you smoke, you may be asked to stop smoking, as this increases the risk of developing a chest infection or deep vein thrombosis (DVT). Smoking can also delay wound healing.

You will need to be nil by mouth for 6 hours before the surgery. This means you can't eat any food for 6 hours, but you will probably be advised that you can drink still unflavoured water (e.g. tap water) up until 2 hours beforehand.

You'll wake up in the recovery room of the operating theatre before being taken back to your floor. You'll have intravenous fluids (a drip) at first but you should be drinking and eating normally the next day.

Patients typically stay in for two days after a PCNL. Your urinary catheter is usually removed the morning after surgery. The small nephrostomy tube coming directly out of the kidney also drains urine. Your urologist will advise on the timing of the removal of this.