Tips & Tricks for Percutaneous Nephrolithotomy (PCNL)

In this episode of BackTable Urology, Dr. Margaret Pearle, an endourologist specializing in complex kidney stone cases, joins Dr. Aditya Bagrodia and Dr. Jose Silva to share her preoperative, intraoperative, and postoperative advice on the percutaneous nephrolithotomy (PCNL) procedure.

First, the doctors discuss preoperative considerations such as absolute indications for PCNL, preferred imaging modalities and urine culture analysis. Dr. Pearle notes that, although every kidney stone patient is a potential candidate for PCNL, PCNL is ideal for patients with large and complex stones and/or patients with no other access options besides percutaneous access. Her preferred imaging modality is CT imaging without contrast, and she emphasizes that a surgeon must study the patient’s collecting system anatomy extensively before operating. Dr. Pearle also adopts an aggressive preoperative antibiotic regimen in patients who present with positive urine culture analyses at least two weeks before the operation.

Then, Dr. Pearle discusses the PCNL operation in the context of achieving percutaneous access, her tools of choice, and operating red flags. She advocates for urologists to learn how to gain percutaneous access without the assistance of an interventional radiologist, but still acknowledges that working with an interventional radiologist is helpful, especially in cases where ultrasound-guided access is needed. She then delineates the type of guide wire, introducer set, sheaths, and nephroscopes she uses and explains how to distinguish the posterior calyx from the anterior calyx using balloon dilation and contrast. Some signs to abort the PCNL procedure are: a significant amount of bleeding, the presence of pus, and a significant perforation of the collecting system.

Finally, Dr. Pearle discusses postoperative decisions, such as whether to place a ureteral stent or a nephrostomy tube. She advises urologists to check the kidney with a flexible nephroscope and to get a postoperative contrast-enhanced ultrasound to confirm that patients are really stone-free. Also, she always gets a chest CT that includes lung bases to check for the presence of a hydrothorax.