Ureteric stents, also known as double J stents or retrograde ureteric stents, is a urological catheter that has two "J-shaped" (curled) ends, where one is anchored in the renal pelvis and the other inside the bladder.
Stents are used for the free passage of urine from the kidney to the bladder, in adverse conditions such as postoperative urologic procedures, and previously to lithotripsy and ureteral obstructions.
Ureteric stents may be placed from an antegrade approach by an interventional radiologist or a retrograde approach by a urologist. Stent placement may replace a percutaneous nephrostomy that has been performed in the acute setting. This is popular with patients as it 'internalises' the method of obstruction bypass without all the negatives of a nephrostomy.
Stents may be uses for a short of long term period depending on the indication:
- obstruction from urolithiasis
- malignant obstruction (typically pelvis malignancies)
- benign strictures
- retroperitoneal fibrosis
Pre procedure evaluation
Room Set Up
The majority of stents are plastic, but metallic stents are now available for use in malignancy to reduce the chance of in growth into the stent. It is a trade off as these stents are significantly more expensive than traditional stents.
A variety of delivery systems exist:
- pusher mechanism
- string release
- sheath (similar to a IVC filter)
Equipment required includes:
- angled 0.035 150cm hydrophilic wire
- 145cm 0.035 Amplatz super stiff wire
- 8F sheath
- ureteric stent (typically 6F, 28cm)
- 8F catheter (for covering nephrostomy)
- analgesic and sedative medications (e.g. pethidine, midazolam)
Post procedural care
- one end of the stent may migrate or in rare circumstances completely dislodge
- urosepsis following the process of insertion
- failure to insert, typically due to a stricture that is impassable
Stents are typically left for a maximum of 3-6 months. If long-term stents are required exchanges (replacement) are usual due to encrustation.