The urine from a normal kidney drains through a narrow, muscular tube, the ureter, into the bladder. When that tube becomes blocked, for example by a stone or a blood clot, the kidney can rapidly become affected, especially if there is infection present as well. While an operation may become necessary, it is also possible to relieve the blockage by inserting a fine plastic tube, called a catheter, through the skin, into the kidney, under local anaesthetic. This catheter then allows the urine to drain from the kidney into a collecting bag, outside the body. This procedure is called a percutaneous (meaning through the skin) nephrostomy (a tube put into the kidney).
Why this procedure?
Other tests will have shown that the tube leading from your kidney to the bladder has become blocked. However, it may not be obvious what the cause of the blockage is. If left untreated, your kidney will become damaged.
What is the procedure?
Generally, you will lie flat on your stomach for the procedure, which is carried out under a local anaesthetic. Using an ultrasound machine will decide on the most suitable point for inserting the fine plastic tube (catheter), usually in your back, just below your twelfth rib. Then your skin will be anaesthetised with local anaesthetic, and a fine needle inserted into the kidney.
When we’re sure that the needle is in a satisfactory position, a guide wire will be placed into the kidney, through the needle, which then enables the plastic catheter to be positioned correctly. This catheter will then be fixed to the skin surface and attached to a drainage bag.
Before, during and afterwards:
Unfortunately, it may hurt a little, for a very short period of time, but any pain you have should be controlled with painkillers. Generally, placing the catheter in the kidney only takes a short time, and once in place it should not hurt at all.
The drainage catheter stays in place in your body for the time being, and will be attached to a collection bag. You will be able to carry on a normal life with the catheter in place. However, it is important that you try not to make any sudden movements, for example getting up out of a chair, without remembering about the bag, and making sure that it can move freely with you. The bag needs to be emptied fairly frequently, so that it does not become too heavy
Sometimes there is a leak of urine from the kidney, resulting in a small collection of fluid inside the abdomen. If this becomes a large collection, it may require draining.
Percutaneous nephrostomy is a very safe procedure, but there are some risks and complications that can arise, as with any medical treatment.
Perhaps the biggest problem is being unable to place the drainage tube satisfactorily in the kidney. If this happens, a surgeon will arrange another method of overcoming the blockage, which may involve surgery.
There may be slight bleeding from the kidney. On very rare occasions, this may become severe, and require a surgical operation or another radiological procedure to stop it.