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What is nephrostomy (Percutaneous Nephrostomy; “PCN”) tube?

It is a small plastic tube that is inserted through the skin and into the kidney, with the tip of the tube located where urine collects.

It drains off urine to a bag that is outside of the body.

Why may I need a nephrostomy tube?

A nephrostomy tube is usually placed for one of these reasons:

  1. There is an obstruction that prevents urine from draining to the bladder. This is most often due to a blockage in the ureter, the conduit that carries urine from the kidney to the bladder.

  2. To divert the urine away from an internal urine leak.

  3. In preparation for a second procedure to remove stones.

When an obstructed system becomes infected, it can cause sepsis (a serious blood infection). In this situation, the nephrostomy tube is often life-saving and (along with antibiotics) relieves the infection.


What are the risks of the procedure?

Image guidance not only guides placement of the drainage catheter, but it also helps avoid inadvertent injury to normal structures deep within the body such as major arteries or veins, organs and bowel. Still, there is a small risk of bleeding or organ injury despite the most careful drain placement.

There is also a small risk that the drainage procedure will initially make the symptoms of infection worse simply by drain placement. Fevers and chills may follow the procedure, but tend to resolve within a few hours.

How is a nephrostomy tube placed?

Your procedure will be done at El Camino Hospital where you will be set up with an IV to allow access for moderate, also known as “twilight” sedation. You will then be taken to the procedure room where you will have a team of two nurses, a radiology technician and your interventional radiologist. You will be connected to heart, blood pressure and oxygen monitors during the entire procedure. IV medication will be administered to make you comfortable (moderate sedation). Using x-ray (fluoroscopy) guidance, your kidney(s) are visualized. A site on the skin of the procedural area is cleaned and sterilized and a local anesthetic is injected in this area to numb the site. Then a small needle is inserted through the skin and into the kidney to the collection area of the kidney. A guidewire is then placed and maneuvered into position, replacing the needle. Once in a good position, a small drainage catheter (nephrostomy tube) is then slid over the guidewire, replacing it. The nephrostomy tube is then anchored in place using a small suture on your skin and attached to a drainage bag. This procedure takes about 20 to 30 minutes

What can I expect after the procedure?

You will recover after your procedure for about 1 hour where your procedure site, heart rate, blood pressure, and oxygen saturation will be monitored. Your family will be able to see you soon after the procedure in the post-operative area and you will be able to eat and drink once you are awake and able to. You should expect to have some mild tenderness and discomfort at the nephrostomy tube site for the next 2-3 days.

How often should I change the nephrostomy bag?

The bag only needs to be changed when it gets dirty, smells bad, or has a lot of blood or clot in it. This is variable, but for most patients, the bag should be changed every 2-4 weeks.

Where can I get new bags?

You should receive an extra bag before you leave the hospital after the insertion of the nephrostomy tube. When you come to your follow-up appointment we can give you an additional bag, if needed. Additional bags can be bought at a medical supply store.

MOUNTAIN VIEW:CAMINO PHARMACY 701 E. El Camino Real – 2nd floor NOREL PROSTHETICS 205 South DriveP: 650.934.7699 P: 650.968.7464FREMONT:HALLERS PHARMACY 37323 Fremont BlvdP: 510.797.2772PALO ALTO:PALO ALTO ORTHOPEDIC 3910 Middlefield rdP: 650.813.9300SAN JOSE:SANTA CLARA OSTOMY AND MEDICAL 2455 Forest Ave BISCHOFF’S MEDICAL SUPPLY 225 North Bascom AveP: 408.296.7890 P: 408.286-6651SANTA CRUZ:HORSNYDER PHARMACY 1226 A Soquel AveP: 831.423.2315SAN FRANCISCO:BISCHOFF’S MEDICAL SUPPLY 1635 Divisadero st. #105P: 415.921.0440

When do I need to flush the nephrostomy tube?

You only need to flush the tube if:

  1. There was drainage into the bag, but it has stopped. This may mean that the tube is clogged. 

  2. There is a significant amount of blood or clot in the urine. It means the tube will likely get clogged.

How do I flush the nephrostomy tube?

Most patients with nephrostomy tubes do NOT need to flush their tubes. But if there is blood or clot in the urine, you may be instructed by your physician to do so to keep the drain from becoming clogged. Learning to flush the drain takes some simple training, but once you understand the procedure it is easy and takes 5 minutes. You must take a small syringe ( 5 – 10 ml ) and fill it with sterile water or saline. There should be a 3-way stopcock in the line between the drain and the bulb. If you have a nephrostomy tube that needs flushing, it will probably have a stopcock between the tube and the drainage bag.

The syringe fits on the side port and the stopcock is rotated into different positions to flush toward the bag or nephrostomy tube.

In this position you CANNOT inject from the sideport.  This is the position for flow from the nephrostomy tube to the bag.  The stopcock should be in this position unless you are flushing the line.

In this position you CAN  inject from the sideport.  This will clear the nephrostomy drainage tube.

In this position you CAN  inject from the sideport.  This will clear the line into the bag.

How do I manage and empty the bag?

You will want to make sure the bag is always hanging below the level of where your catheter is placed. Periodically check throughout the day that the tubing is not kinked or appear clogged. If there is debris in the tubing and you are concerned it may be causing a blockage, you can strip or milk the tubing by pinching the tube and sliding your fingers down towards the bag. If you have a stopcock or Y-connector then you can flush the tube also.

To empty the drain, locate the blue cap at the bottom of the bag. This cap is actually a valve. If you turn it one way it will open up and allow fluid from the bag to drain out. Before you do anything, make sure to record the amount of fluid in the bag and wash your hands thoroughly with soap and water. Turn the blue cap until fluid starts to come out and empty the contents of your gravity bag into the skin or toilet. Once completed make sure to turn the blue cap back to its original “closed” position so fluid does not leak!

How to care for the skin and the nephrostomy tube insertion site ?

  1. Wash your hands well with soap and water.

  2. Remove the dressing from around the nephrostomy tube insertion site. Use soap and water or saline or peroxide on a gauze pad/cotton pad. Clean this area once a day.

  3. When the catheter site is clean and dry, place a new dressing around the drain. Put surgical tape on the dressing to hold it down against your skin.

  4. If it is bloody or soiled, wrap the dressing in a small plastic bag. and place into the trash.

  5. Wash your hands.

How long will the nephrostomy tube stay in place? 

Usually the nephrostomy tube is removed after the original problem is fixed (ie. removing the kidney stone or tumor, resolution of infection).  But it will stay in place as long as necessary.  In your case, it will stay until after your delivery.

How is nephrostomy tube removed? 

We usually remove them under x-ray guidance because we like to check the kidney to be sure everything looks good and there is no more residual obstruction before we remove it.  Also this way we can make sure there is no significant bleeding from the drain site. 

When should you call your physician?

Fever or chills > 101 F

Worsening of redness or worsening of pain in the procedure area

Significant bleeding for >24 hours

If the drain gets clogged.

If the drain gets accidentally removed.

You can reach your Interventional radiologist at 650-404-8445 (ask for the Interventional Radiology Clinic).

General Instructions:

  • If you received sedation, you should not drive, consume alcohol, operate heavy machinery or make any important decisions for the remainder of the day.

  • You may resume your regular activities (including driving) after 24 hours, unless you have been restricted for another reason.

  • No exercising, lifting heavy objects or strenuous activity for the next 24 hours.

Pain Management
  • You may use over the counter medication such as Acetaminophen (tylenol) or Ibuprofen (Advil /Motrin) for minor discomfort, unless you are restricted from taking these medications.

  • For more severe pain, we will prescribe Norco (Hydrocodone + tylenol), which is a narcotic medication.

  • You should also take Colace (stool softener) daily while taking the narcotic medication to prevent constipation, which is a common problem while taking these medications.

  • You can resume your normal diet. Some patients may develop nausea after the sedation. Therefore light meals are recommended until you know that you can eat without problems.

  • You can take a shower tonight.


  • After the shower, you should remove the dressing, dry the area and apply a new dressing.

  • You should not soak the tube insertion site in water (eg. bath and swimming pool)

Blood in the urine
  • It is normal to have some bloody urine for up to a week after the procedure, and do not be surprised if your urine looks like the color of cranberry juice or rosé wine, as long as it is relatively clear.

  • Even after a week, you can occasionally have some occasional blood in your urine.

  • If you cannot see through it, or there is blood that is clotting in the tube or the bag, there is risk the tube can get clogged and then the tube should be flushed (see the instructions above).

  • You should call your interventional radiologist if the blood is thick enough that you cannot see through the urine for more than 24 hours.

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