From the Guidelines
Percutaneous nephrostomy is a safe and effective medical procedure where a thin tube (catheter) is inserted through the skin into the kidney to drain urine when normal drainage is blocked, with a technical success rate approaching 100% when performed with image guidance, as demonstrated by a large UK registry with data from over 3,000 PCN procedures 1.
Procedure Overview
Percutaneous nephrostomy (PCN) entails placing a drainage catheter into the renal collecting system, typically using imaging guidance and the Seldinger needle-wire technique, to provide access for urinary decompression or internal drainage through the ureter and bladder 1. The procedure is usually performed under local anesthesia with imaging guidance, such as ultrasound or fluoroscopy.
Indications and Success Rates
Common indications for PCN include kidney stones blocking the ureter, tumors compressing the urinary tract, blood clots, or strictures preventing normal urine flow. The technical success rate for PCN placement is high, with rates >95% when accessing dilated collecting systems and approximately 80% to 90% when accessing nondilated systems 1. The Society of Interventional Radiology quality improvement (SIR QI) guidelines set threshold percentages for technical success rates for PCN at 95% for urinary obstruction without stones, including renal transplant obstruction 1.
Complications and Management
Complication rates related to PCN are low, usually reported at 10% 1, with a UK registry data showing an even lower rate of 6.3% 1. The SIR QI guidelines have suggested thresholds for PCN complications, including septic shock at 4% 1. Patients with nephrostomy tubes need to keep the insertion site clean and monitor for signs of infection, such as fever, increased pain, or cloudy, foul-smelling urine. The tube typically requires periodic changes every 2-3 months if left in place long-term.
Importance of PCN
This intervention is crucial for preserving kidney function by relieving pressure from backed-up urine, which if left untreated could lead to kidney damage or infection. The procedure is often temporary until the underlying cause of obstruction can be treated, though in some cases it may remain in place longer, highlighting the need for careful patient selection and management 1.
From the Research
Definition and Purpose of Percutaneous Nephrostomy
- Percutaneous nephrostomy (PCN) is a medical procedure used to divert urine directly from the kidneys when there is a blockage or obstruction in the urinary tract 2, 3.
- The purpose of PCN is to relieve urinary obstruction, prevent kidney damage, and improve symptoms associated with urinary retention or leakage.
Procedure and Guidance
- PCN can be performed under ultrasound and fluoroscopic guidance, which helps to visualize the kidney and surrounding structures during the procedure 2.
- The use of ultrasound contrast agents can also enhance the success rate of PCN in non-hydronephrotic kidneys by providing better visualization of the renal collecting system 3.
Success Rate and Complications
- The technical success rate of PCN can vary depending on the guidance method and patient characteristics, with reported success rates ranging from 83.3% to 100% 2, 3.
- Complications of PCN can include bleeding, transient gross hematuria, and radiation exposure, although these are generally rare and minor 2.
- The use of UCA-assisted US guidance PCN has been shown to have a high success rate and safety profile, with no serious complications reported in one study 3.