PCNL (Percutaneous Nephrolithotomy)

PCNL may be considered when kidney stones exceed 2 centimetres in diameter. Stones of this size does not pass naturally and often resist fragmentation through external shockwave lithotripsy (ESWL) or may not even be completely cleared after multiple procedures of Retrograde Intra Renal Surgery (RIRS). PCNL are also suitable for stones located all parts of the kidney especially in the lower pole, where other treatments may be less effective.

Staghorn calculi, which branch into multiple areas of the kidney’s collecting system, require PCNL for effective removal within 1 sitting. These complex stones can occupy large portions of the kidney and pose risks such as infection, bleeding and kidney failure if left untreated.

Patients who have undergone unsuccessful ESWL or ureteroscopy or RIRS are also candidates for PCNL. Some stones are too hard or too large to fragment effectively with shockwave therapy or ureteroscopy or RIRS. When multiple sessions with other modality fail to achieve adequate stone clearance, PCNL can provide an alternative treatment approach to achieve complete stone clearance.

Certain medical conditions may make PCNL a more suitable treatment option. Patients with urinary tract abnormalities, such as horseshoe kidneys or ureteropelvic junction obstruction, may be more suitable for stone removal with PCNL. Patients with cystine stones or other hard stone compositions may benefit from PCNL compared to other treatments.

Before PCNL surgery, a comprehensive evaluation aims to support treatment planning. Blood tests assess kidney function, blood clotting ability, and check for infection. Urine culture identifies any bacterial infection that may require pre-operative antibiotics. CT scanning provides detailed stone mapping, helping the surgeon plan the access route.

Patients may need to stop blood-thinning medications before surgery under medical supervision. Fasting from midnight before the procedure is required for general anaesthesia safety. Pre-operative antibiotics may be prescribed to help reduce infection risk.

PCNL is performed under general anaesthesia in an operating theatre equipped with imaging technology. The procedure begins with the patient positioned prone (face-down) or in a modified position, depending on the stone location. Using ultrasound or X-ray guidance, the urologist inserts a needle through the skin into the kidney’s collecting system.

A guidewire is passed through the needle, and the tract is gradually dilated to accommodate a nephroscope (thin telescope). Through this instrument, the surgeon can visualise the stone directly. Laser, ultrasonic, or pneumatic energy instruments fragment the stone into small pieces for removal. A nephrostomy tube or internal stent may be placed to support drainage during healing.

Patients may stay in the hospital following PCNL. The nephrostomy tube, if placed, may be removed once urine clears. Pain management includes oral medications, with patients potentially experiencing mild to moderate discomfort.

Return to light activities may occur within a period determined by your healthcare professional, though heavy lifting and strenuous exercise should be avoided as advised. Follow-up imaging aims to assess stone clearance and kidney healing.

Traditional PCNL uses a 24-30 French access tract, allowing the use of standard nephroscopes and instruments. This approach provides visualisation and stone removal for large stone burdens. The larger tract accommodates various fragmentation devices and extraction instruments simultaneously.

Stone fragmentation occurs through ultrasonic, pneumatic, or laser lithotripsy. Ultrasonic devices combine fragmentation with suction for removal. Laser lithotripsy offers fragmentation with minimal tissue trauma. Stone fragments are extracted using graspers, baskets, or suction devices.

Mini-PCNL utilises smaller access tracts (18 French or less), which may reduce tissue trauma while maintaining effectiveness. This technique is suitable for medium-sized stones and selected larger stones in favourable locations. Smaller instruments may mean longer operative time, but could potentially support faster recovery.

The miniaturised equipment includes smaller nephroscopes with improved optics and specialised laser fibres for stone fragmentation. Reduced tract size may decrease bleeding risk and post-operative pain, though stone clearance rates can be comparable to standard PCNL for appropriate cases.

These techniques use smaller access tracts (11-13 French for ultra-mini, less than 10 French for micro-PCNL). They may be suitable for smaller stones in challenging locations or paediatric patients. The instruments require specialised expertise and equipment.

High-powered laser systems can compensate for limited fragment extraction capability. These approaches often achieve fragmentation of stones into sand-like particles that may pass naturally. Recovery time and complications may be reduced, though procedure duration might increase.

Hospital stay may last several days, depending on the procedure’s complexity. Vital signs and urine output are monitored closely. The nephrostomy tube, if present, drains blood-tinged urine that gradually clears.

Pain management begins with intravenous medications, transitioning to oral painkillers. Patients may walk within hours of surgery, which can promote recovery and help prevent complications. Diet progresses from clear fluids to regular meals as tolerated.

Discharge occurs once pain is controlled and urine drainage is satisfactory. Oral antibiotics may continue for several days. Pain medication is used as needed, with some patients requiring minimal pain relief after the first week.

Activity gradually increases over several weeks. Light walking is encouraged immediately, while heavy lifting and strenuous exercise are avoided initially. Some patients may return to desk work within a week and physical work within several weeks. 

Imaging studies may be performed to confirm stone clearance and kidney healing. Residual fragments, if present, may pass naturally or require additional treatment. Metabolic evaluation can help identify stone risk factors for prevention strategies.

Regular monitoring may include periodic imaging for high-risk patients and stone analysis if fragments are passed. Dietary counselling and medical therapy can help reduce recurrence risk. Long-term kidney function monitoring aims to ensure no delayed complications develop.