📖 What is nephrostomy?
A percutaneous nephrostomy (PCN) is a drainage catheter inserted through the skin directly into the kidney collecting system under imaging guidance (ultrasound ± CT). It relieves urinary obstruction when urine cannot drain normally through the ureter into the bladder — due to a tumour, stone, stricture, or external compression.
PCN is performed under local anaesthesia, usually as an urgent or semi-urgent procedure. It is the first step in relieving obstructive nephropathy and may be followed by anterograde ureteric stent placement.
🎯 Indications
- Ureteric obstruction by pelvic or retroperitoneal tumour (cervical, bladder, prostate, colorectal cancer)
- Obstructive ureteric stone not amenable to ureteroscopy
- Ureteric stricture (post-radiation, post-surgical, inflammatory)
- Infected obstructed kidney (pyonephrosis) — emergency drainage
- Bridge to definitive treatment (ureteric stent, surgery)
🔧 Procedure
CT urogram or ultrasound to assess degree of hydronephrosis and plan optimal access route.
Patient prone. Local anaesthesia at the posterior lumbar puncture site. Ultrasound guidance for initial calyceal puncture.
Seldinger technique: needle → guidewire → serial dilation → nephrostomy catheter (8–10 Fr). CT fluoroscopy for complex or ectopic kidneys.
PCN drain left to external drainage bag. If ureteric passage possible: anterograde ureteric stent insertion over the guidewire to re-establish internal drainage.
Catheter secured. Output monitored. Creatinine check at 24 and 48 hours. Tube change every 2–3 months.