Percutaneous nephrolithotomy, or PCNL, is performed under general anesthesia. During the procedure, your doctor makes a small incision in your side about the size of a fingertip. A narrow tunnel is then created directly into the kidney. A special telescope (called a nephroscope) is used to examine the inside of the kidney. Stones are broken by high speed vibration or a laser. This procedure usually requires a one to three day hospital stay and most patients resume normal activity within two weeks.
Traditional percutaneous nephrolithotomy
Traditional PCNL involves a series of steps performed over several days.
- On the first day, a tract is established into the kidney and the doctor tries to remove all stones. A nephrostomy tube (a soft plastic tube that is inserted though the back and into the kidney) is left in to help the kidney drain.
- The day after surgery, a CT scan is performed to look for any remaining stones.
- If stones remain, a "second look" procedure may be performed on day two or three through the existing tract or, if necessary, new access tracts are created.
- When all stones are cleared, x-ray contrast media is injected into the nephrostomy tube to ensure that the kidney is draining well. If it is, the nephrostomy tube is removed. If the kidney is not draining well, the nephrostomy tube may be left in for a few more days or an internal ureteral stent may be placed temporarily until the kidney and ureter recover from surgery.
Tubeless Percutaneous Nephrolithotomy
During a tubeless procedure, stones are removed in the same way as traditional PCNL. The difference comes at the end of the procedure. If the urologist is confident that all stones are cleared, a ureteral stent is inserted in place of a nephrostomy tube.
If all stones cannot be cleared during the initial procedure or if there is significant bleeding during the procedure, patients must undergo traditional PCNL.
Advantages of the tubeless procedure
- Most patients leave the hospital after overnight observation.
- Many require half the pain medication.
- At the HealthEast Kidney Stone Institute, 90% of patients with large, complex stones are able to have the tubeless procedure.
Who is a candidate for PCNL?
While PCNL can be used to treat stones in any location and of any size, it is often reserved for the largest and most complex stones:
- Kidney stones treated with PCNL are usually larger than 1.5 cm or cannot be effectively treated with or ureteroscopy.
- On occasion, smaller stones may be treated by PCNL if there is a history of serious infection or if the kidney is malformed.
- If a nephrostomy tube has already been inserted for emergency drainage, it may be used to complete PCNL treatment
Who is not a candidate for PCNL?
PCNL is the only way to effectively treat large and complex stones, short of open kidney surgery. There are very few patients with these difficult stones who should not be treated with PCNL. In rare cases where the patient is too fragile or the stone has already destroyed the kidney, the doctor may decide not to treat the stones, but instead to remove the kidney.
PCNL may NOT be a good option for those with the following. Ureteroscopy may be a better option.
- Stone less than 10 mm
- Morbid obesity (patients who weigh more than 450 pounds)
- Patients on blood thinners
What is the treatment success rate?
It is difficult to generalize about the success rate of PCNL because it is often used for the most complex stones and patients. In our experience, about 90% of patients with complex stones can be succesfully treated with a single PCNL procedure. We strictly adhere to the philosophy that large and complicated stones must be completely removed to minimize the recurrence of similar stones.
What should I expect after treatment?
- Blood in the urine, as long as a stent or nephrostomy tube is in place
- For patients with a stent:
- You may need to urinate frequently
- You may have discomfort in your back as you begin to urinate
- There may be discomfort in your bladder when urination is near complete
- For patients with a nephrostomy tube:
- It may be uncomfortable to sleep on the side with the tube
- You may experience urine leakage around the tube
- After the tube is removed, urine may leak out for 1-2 days
- The incision in your back may be uncomfortable but should not be painful
- It is normal to feel tired for up to one month
What follow-up is required after PCNL?
If your doctor suspects that stone fragments remain after PCNL, a CT scan will be performed the day after surgery to plan further treatment.
If your doctor thinks all stones have been cleared, a CT scan will be performed one month after surgery to confirm that stone fragments have been cleared and to check on the kidneys.
What should I watch out for after surgery?
- Blood clots in urine - may be a sign of kidney bleeding
- Abdominal pain - may be a sign of urinary leakage
- Shortness of breath - may be a sign of fluid in the chest
- Fever - may be sign of kidney infection
- Persistent leakage from nephrostomy site - may be a sign of an obstructed ureter