Percutaneous Nephrolithotomy (PCNL) is a minimally invasive technique for removing kidney stones that are too large to deal with from below.
A general anaesthetic is required.
A fine needle is placed into the kidney through the back and this access is gradually dilated up until a 10mm tube can be placed.
This tube allows the passage of a telescope through which a laser fibre can be placed in order to break up the stone under direct vision.
The stone fragments can then be removed directly as seen in the video (click here).
Following stone removal a drainage tube (nephrostomy) is placed into the kidney - this usually stays in overnight.
A catheter tube will be placed whilst you are under aneasthetic and, like the nephrostomy tube is usually removed the following day.
This is not usually a particularly painful procedure and most patients will be able to receive visitors 3-4 hours postoperatively. You will be able to eat and drink that afternoon.
The nephrostomy is usually clamped the next morning and if there is no leakage or pain it can be removed. It is quite common for the site to drain fluid for several hours afterward.
Most patients will only need one night in the hospital but it is important that you do not overdo it for 6 weeks after surgery to allow the wound in the kidney to heal.
All surgical procedures are associated with some risk, the general risks include the development of wound infection, blood clots, and pneumonia, but in practice these are rare.
The specific risks of PCNL are outlined below:
Bleeding: The kidney is a very vascular organ receiving 20% of the circulating blood volume every minute. PCNL involves drilling a hole right through the meat of the kidney. Knowledge of the renal anatomy allows the needle used to obtain access to be carefully placed in order to avoid the major vessels but bleeding does sometimes occur. Often the bleeding stops on its own but occasionally the procedure may need to be abandoned due to lack of vision or, in severe cases, the bleeding vessel needs to be embolised by the radiologists. The incidence of bleeding severe enough to require this is less than 5%. It is theoretically possible that very severe bleeding may require the removal of the kidney. We have never had to do this.
Incomplete stone clearance: This complication is largely determined by the anatomy of the stone. Some stones are very large and multiple procedures may be planned, others may be in awkward to get places. In general, the risk of incomplete clearance can be determined prior to the procedure but occasionally stones that look easy on X-ray can be fiendishly difficult at operation. Very rarely (<2% of cases), it is just not possible to get into the collecting system.
Sepsis: This is a very serious potential complication of PCNL (and in fact all stone surgery), which is more common in so-called "infection stones". Patients at increased risk will be treated pre-operatively with a week of antibiotics in addition to the antibiotics given intravenously at the time of surgery.
Damage to the collecting system: This occurs when the dilators puncture through the wall of the renal pelvis or, more commonly, there is a tear or split in the intrarenal infundibulum. This complication is usually of no consequence, although very occasionally the nephrostomy tube may need to be left for longer than usual.