When the passage between a person's kidneys and bladder becomes blocked, a doctor may perform a procedure to insert a urinary stent into the tube between them, the ureter. First, it is necessary to determine which size and type of stent is best suited to the patient's needs. The procedure is typically performed in the hospital, under general anesthesia, though in some cases the patient is kept awake and given local anesthesia. Placement of the stent is usually accomplished by insertion through the urethra, which is the tube that leads from the bladder out of the body, though in certain cases an incision through the skin may be needed to reach the ureter.
There are a number of different types of urinary stent, and the right one needs to be chosen for a patient before the procedure can be done. Depending on the patient's needs and physiology, different materials, sizes, and designs of stent might be used. For example, a patient getting a stent put in temporarily may be better suited for an open-ended stent, while someone having one placed more permanently may fare better with one that has coiled ends to hold it in place. A stent may also have a string attached for the doctor to later pull it out, or it may not if the doctor intends to remove it with a cytoscope.
Once the appropriate urinary stent is chosen, the patient will need to be prepped for the procedure. The doctor may do a physical examination, take a urine sample, or run some blood tests to ensure the patient is in good enough physical health for it. Ureteral stenting is usually performed in the hospital, though it may not require an overnight stay. Typically, it is performed while the patient is under general anesthesia, though in some cases the person may be awake and only receive local anesthesia.
Placement of a urinary stent often requires no surgery. Entering the body through the urethra, the doctor will run a thin, flexible instrument called a cytoscope up through the bladder to the ureter. A guide wire may also be inserted, which can then be viewed on a screen using a fluoroscope for easier placement of the stent. The wire and cytoscope are then withdrawn from the body. While this is the preferred method for inserting a urinary stent, it is not successful in all patients. In those cases, a surgical incision may be made in the skin, and the stent inserted via the kidney.