Definition
Nephrostomy is a procedure in which a catheter (plastic tube) is inserted through the skin and into the kidney to drain it of urine. Urine drains into a bag outside the body.
Purpose
The ureter is the tube that carries urine from the kidney to the bladder. When this tube is blocked, urine backs up into the kidney. Serious, irreversible kidney damage can occur because of this backflow of urine. Infection is also a common implication in this stagnant urine.
Nephrostomy is performed in several different circumstances:
- when the ureter is blocked by a kidney stone
- when the ureter is blocked by a tumor
- when there is a hole in the ureter or bladder and urine is leaking into the body
- as a diagnostic procedure to assess kidney anatomy
- as a diagnostic procedure to assess kidney function
Precautions
People preparing for a nephrostomy should review with their doctors all the medications they are taking. People taking anticoagulants (blood thinners such as Coumadin) may need to stop medication. People taking metformin (Glucophage) may need to stop taking the medication for several days before and after nephrostomy. Diabetics should discuss modifying their insulin doses because fasting is required before the procedure.
Description
Nephrostomy is done by an interventional radiologist or urologist with special training in the procedure. It can be done either as an inpatient or an outpatient procedure, depending on why it is needed. For most cancer patients, nephrostomy is an inpatient procedure that is covered by insurance.
First, the patient is given an anesthetic to numb the area where the catheter will be inserted. The doctor then inserts a needle into the kidney. There are several imaging technologies such as ultrasound and computed tomography that are used to help the doctor guide the needle into the correct place.
Next, a fine guide wire follows the needle. The catheter, which is about the same diameter as IV tubing, follows the guide wire to its proper location. The catheter is then connected to a bag outside the body that collects the urine. The catheter and bag are secured so that the catheter will not pull out. The procedure usually takes one to two hours.
Preparation
Either the day before or on the day of the nephrostomy, blood samples will be taken. Other diagnostic tests done before the procedure vary depending on why the nephrostomy is being done, but the patient may have a computed tomography (CT) scan or ultrasound to help the doctor locate the blockage.
Patients should not eat for eight hours before a nephrostomy. On the day of the procedure, the patient will have an intravenous (IV) line placed in a vein in the arm. Through this the patient will receive antibiotics to prevent infection, medication for pain, and fluids. The IV line will remain in place after the procedure for at least several hours, and often longer.
Aftercare
Outpatients will be expected to stay about 8–12 hours after the procedure to make sure the catheter is functioning properly. They should plan to have someone drive them home and stay with them at least the first 24 hours after the procedure. Inpatients may stay in the hospital several days. Generally people feel sore where the catheter is inserted for about a week to ten days.
Questions to Ask the Doctor
- Why am I having a nephrostomy?
- How long do you think I will have to stay in the hospital?
- How long do you expect the catheter to stay in?
- How much help will I need in caring for the catheter?
Care of the catheter is important. The catheter will be located on the patient's back, so it may be necessary to have someone help with catheter care. The catheter should be kept dry and protected from water when taking showers. The skin around it should be kept clean, and the dressing over the area changed frequently. Special care is needed in handling the urine collection bag so that it does not dislodge the catheter.
Risks
Nephrostomy is an established and generally safe procedure. As with all operations, there is always a risk of allergic reaction to anesthesia, bleeding, and infection.
Normal Results
In a successful nephrostomy, the catheter is inserted, and urine drains into the collection bag. How long the catheter stays in place depends on the reason for its insertion. In people with pelvic cancer or bladder cancer where the ureter is blocked by a tumor, the catheter will stay in place until the tumor is surgically removed. If the cancer is inoperable, the catheter may have to stay in place for the rest of the patient's life.
Abnormal Results
Bruising at the catheter insertion site occurs in about half of people who have a nephrostomy. This is a minor complication. Major complications are infrequent, but include the tube becoming blocked or dislodged requiring tube replacement, bleeding and blood in the urine, and perforation of other organs.
Resources
Other
American Cancer Society. National Headquarters, 1599 Clifton Road NE, Atlanta, GA 30329. 800–ACS–2345.
Cancer Information Service. National Cancer Institute, Building 31, Room 10A19, 9000 Rockville Pike, Bethesda, MD 20892. –800–4–CANCER.
"Nephrostomy," Mid-South Imaging and Therapeutics. [cited April 30, 2001 and June 27, 2001].
—Tish Davidson, A.M.
