What is the purpose of placing a stent in the kidney?

From the Guidelines

A kidney stent is placed to maintain urine flow from the kidney to the bladder when there is an obstruction or blockage in the urinary tract, with the primary purpose of bypassing obstructions such as kidney stones, tumors, or scar tissue that prevent normal urine drainage, as supported by recent studies 1. The purpose of placing a stent in the kidney is to relieve pressure in the kidney, prevent infection, and allow healing after procedures like ureteroscopy or lithotripsy.

Key Points

• Kidney stents are typically made of silicone or polyurethane and have small holes throughout their length to allow urine to flow.
• They may be placed temporarily (weeks to months) until the underlying issue resolves or permanently in cases of chronic obstruction.
• Kidney stents work by creating an artificial pathway for urine, preventing urine backup that could lead to kidney damage, pain, or infection.
• While in place, patients may experience side effects like urinary frequency, blood in urine, or discomfort during urination, but these symptoms are generally manageable and temporary, as noted in a study published in the Journal of the American College of Radiology 1. Some of the benefits of kidney stent placement include improved renal function, survival benefits, and quality of life, as reported in a study published in 2020 1.

Considerations

• The decision to place a kidney stent should be made on a case-by-case basis, taking into account the individual patient's needs and medical history.
• Patients with advanced disease or poor performance status may not benefit from kidney stent placement, and alternative treatment options should be considered, as discussed in a study published in 2020 1.
• The procedure itself is not without significant morbidity, and patients should be closely monitored for potential complications, such as pyelonephritis or tube dislodgement, as noted in a study published in 2020 1.

From the Research

Purpose of Placing a Stent in the Kidney

The purpose of placing a stent in the kidney is to:

• Ensure sufficient urine flow in the ureter when there is ureteral stenosis or obstruction, which can cause interruption of normal urine flow and result in renal failure 2
• Relieve the congestion of urine in the upper urinary tract when there is ureteral stenosis or obstruction 2
• Prevent urological complications, such as leaks, obstructions, and urinary tract infections, in patients undergoing renal transplantation 3
• Allow for the functional and morphological recovery of the kidney after relief of obstruction in patients with impacted ureteral stones 4

Types of Stents and Their Effects

• Double J stents are commonly used to alleviate ureteral obstruction, but they can cause stent-related symptoms, such as pain and urinary symptoms 5
• Pigtail suture stents have been shown to reduce stent-related symptoms compared to conventional double J stents 5
• The size of the stent can affect urine flow, with smaller stents (5Fr) resulting in larger total flow rates than larger stents (6Fr-8Fr) 2

Complications and Risks

• Stent-related complications, such as stent fragmentation, migration, and breakage, can occur 6, 3
• Urinary tract infections and other complications can also occur, especially if the stent is left in place for an extended period 6, 3
• Close follow-up and monitoring are necessary to detect and manage any complications that may arise 6