Percutaneous Nephrolithotomy (PCNL)
PCNL is surgery to remove large kidney stones using a telescope which is inserted through a 2cm incision in the flank.
Instruments can be inserted through the telescope to fragment and remove the stones.
Smaller stones are best dealt with in a less invasive way through flexible ureteroscopy and LASER.
Procedure
PCNL is performed under a general anaesthetic. Intravenous antibiotics are given. Firstly, a cystoscopy is performed. This allows the urologist to pass a thin catheter up into the kidney. Dye is injected through this catheter to help guide insertion of the large telescope through the flank. Next, the patient is carefully rolled face down so that the back is exposed. Using a combination of x-ray and ultrasound guidance the kidney is located and a needle inserted through the skin and into the kidney. This needle track is then dilated so that the large telescope is able to be inserted. Once the telescope is inside of the kidney the stone is located and treated. Once all visible stone fragments have been retrieved the telescope is removed and a small tube (nephrostomy tube) is left in the kidney which drains into a collection bag. This tube stays in place for several days before being removed. A temporary ureteric stent (long soft plastic tube) may be left running between the kidney and the bladder. This helps urine drainage while healing occurs. A urethral catheter will also be left in place.
Pre-procedure
Aspirin, clopidogrel, dabigatran, warfarin and any other blood thinning medications will need to be stopped prior to surgery. We will advise you on the timing of when to stop and re-start these medications.
A urine sample will need to be taken 1 week prior to surgery.
Post-procedure
You will have some flank discomfort which is usually well controlled with oral painkillers. You will be able to drink and eat that evening. Most people are able to get out of bed the following day and move about. The urinary catheter and nephrostomy tube are removed before discharge home. The usual length of hospital stay is 3 nights. There will be blood in your urine for several weeks, this gradually clears spontaneously.
A CT scan will be performed several weeks after surgery to ascertain whether there are any residual stone fragments present. If so then further treatment with flexible ureteroscopy or ESWL may be needed. The ureteric stent will be removed within three months of surgery.
Return to Work
Most people can return to a sedentary job by two weeks. Heavier work entailing lifting and straining should be avoided for six weeks.
Risks
Bleeding
Puncturing the kidney leads to bleeding. This is not usually enough to require a blood transfusion. If there is heavy bleeding during or after surgery then this may be due to injury to an artery within the kidney; this happens in less than 5% of cases. The treatment for this is embolisation of the bleeding artery and this is performed by a radiologist. A long catheter is fed into the artery in your groin then up into the kidney. The bleeding vessel is identified then injected with small metal coils which occlude the artery. Rarely the kidney may need to be removed in cases of severe bleeding.
Injury to other organs
Injury to other organs, such as the bowel, spleen, or pleura (membrane surrounding the lungs). A pleural injury may require insertion of a chest tube to drain fluid and air from this area. This complication is more likely if the upper part of the kidney is being operated on. Injury to the bowel or spleen may not be initially evident however will require further surgery to resolve. These are uncommon complications.
Failure to access the kidney
Failure to access the kidney, requiring termination of the procedure.
Incomplete stone clearance
Incomplete stone clearance, requiring further procedures to clear the stone. Small or large fragments are often retained. This is more likely in the case of large stones and in cases where the internal architecture of the kidney prevents easy assess to all areas.
Sepsis
This is a serious potential complication of PCNL and more likely in large 'infection stones' which are colonised with bacteria. In these cases antibiotic therapy is given for one week prior to surgery.