Kidney: Nephrostomy and related catheters and stents


Overview of Nephrostomy tubes for patients:

Nephrostomy tubes are small catheters placed into the kidneys by Interventional Radiologists. They are used to drain urine from the kidney, usually when your kidney is blocked and unable to drain urine on its own. It is important for the kidney to be able to drain urine, so that it does not permanently become damaged. The kidneys are a very important that filter the blood and control your blood pressure.

The nephrostomy tubes are usually placed with you laying on your stomach while we give you medication to moderately sedate you (twilight). People need the tubes for different lengths of time depending on what’s blocking the kidneys. If you need them long term, they need to be changed every 2-3 months.  


These procedures are performed by the interventional radiologists using the assistance of fluroscopy and ultrasound. Access is obtained by a special needle into the renal collecting system via the calyx by percutaneous approach. After confirming the positio by injecting small amount of contrast, a drainage catheter is placed over an wire and is connected to drainage bag and is secured with suture at the skin entry site.



Different versions of Nephrostomy tubes:

Classic Nephrostomy tube:

The tube travels from the skin in your back to the kidney collecting system. The tube is connected to a bag which collects your urine. This is the most commonly used tube and simply drains the urine as soon as it is made and enters the collecting system. This is usually done if the blockage is somewhere in your ureter (the tube that connects the kidney to your bladder).

Nephroureteral stent:

Similar to the Nephrostomy tube, the tube travels from the skin your back to the kidney collecting system. However, the tube continues down your ureter and is coiled in the bladder. This is done in some circumstances to bypass the obstruction and allow your kidney to drain to your bladder. But we keep the tube coming out of your back, so that we don’t lose access to your kidneys.

Ureteric stent/ JJ stent:

The ureteric stent is placed similarly to a Nephroureteral stent at the beginning. However, at the end of the procedure, it no longer travels out of your kidney to your back. This is placed if we have a plan for the urologists to later remove or exchange the stent, because we longer have access to that kidney. The urologists can do this with a scope through your urethra that travels to your bladder (rather than kidney).

Special situations:

Sometimes, there are more complicated situations which require a combination of catheters to be used. For example, a Nephrostomy tube may be placed along with a ureteric stent. This may done when we are attempting to drain your bladder with the internal stent, but keep the nephrostomy tubes as a backup. The nephrostomy tubes can be capped (closed off), so that we can test if the stent is working and you are able to urinate.

What is a Nephrostomy tube?

A Nephrostomy tube is a small catheter that is inserted into the kidney’s collecting system (where urine begins to travel down to the bladder) and comes out of your back to drain urine.  


What does the Kidney do?

The kidney is one of the critical organs of the body and has many functions, including filtering the blood , removing toxins, and regulating blood pressure and the amount of fluid within the body.

How do the kidneys work?

The kidneys have an elaborate and well-organized system to filter the blood that comes in through your arteries to the kidney. Most things are reabsorbed into the body. However, toxins and other molecules are eventually filtered into urine to pass from the kidney to your kidney’s collecting system. The urine then travels down the ureter into your bladder, where urine is stored until you urinate through your urethra.

Why are Nephrostomy tubes placed?

Nephrostomy tubes are most commonly placed to protect the kidneys. It is critical for you to be able to get rid of the urine made by your kidneys. The kidneys cannot function if they are blocked for any reason. If the kidneys are blocked, they may get damaged and eventually fail. Some common causes of your blockage in your urinary system are listed below.

Common causes of obstructive uropathy (blocked kidneys):
Kidney stones
Bladder and kidney cancers
Female genitourinary cancers, such as cervical, ovarian and uterine cancers
Male genitourinary cancers, such as prostate cancer
Benign prostatic hypertrophy
Kidney stones (nephrolithiasis) are the most common causes of hydronephrosis (blocked kidneys). There are several different treatments that are used for treatment of kidney stones. Sometimes, our urologist colleagues can remove or fragment the stones with extracorporeal shockwave lithotripsy or with ureteroscopy. Other times, you require Nephrostomy tubes to drain urine and protect the kidneys when the stone is unable to be taken out.

Who places Nephrostomy tubes?

Nephrostomy tubes are placed by interventional radiologists, specialized doctors that use imaging to perform minimally invasive procedures. They work in collaboration with urologists and nephrologists to find the best way to protect your kidneys.

How are the Nephrostomy tubes placed?

Nephrostomy tubes are placed in an angiography suite with access to ultrasound and fluoroscopy. At the beginning of the procedure, you are generally given a couple medications to provide you with pain relief and sedation. Generally, you do not have to undergo general anesthesia requiring a breathing tube. You lay face down on the table and a local numbing medication is injected over your kidneys. During this portion of the procedure you will feel a small poke, followed by a burning sensation, which quickly improves, and you shouldn’t feel pain. After this, ultrasound is used to find the collecting system of your kidneys where urine concentrates. Under ultrasound guidance, a needle is passed through your kidney tissue into the collecting system. After access is obtained, a few more steps are performed with wires, catheters, contrast (X-Ray dye) to eventually thread the Nephrostomy tube into your collecting system. All of this is done with a tiny poke incision in your back. Once the Nephrostomy tube is in, it is sutured to your back and usually connected to a bag that collects the urine.

Is it painful?

Local anesthetic (Lidocaine) will be used to numb the skin over the kidneys. This causes a “burning” sensation which quickly improves. You may experience some pressure during the procedure, which can be painful. However, we are monitoring for any pain you have, and our nurse can adjust your IV pain medications as needed.

What are the potential complications?

Complications with Nephrostomy tube are fortunately rare. The biggest risk of placement is major bleeding requiring treatment in 1-3.6% of patients. Treatment is usually done by interventional radiologists, the same doctors that placed the tube. Treatnent involves blocking the small blood vessel that is bleeding.
Other complications include infection and sepsis (1-2%), pneumothorax (less than 1%), minor bleeding that resolves within a few days. The most common complications are catheter-related problems. Over time, you may accidentally dislodge your catheter, which requires us quickly replacing the catheter. Catheter blockage is luckily rare (1%).

Is it normal to have a little bit of blood in my urine after the procedure?

Some patients will have slightly blood-tinged urine for a few days after the procedure. Usually, this resolves within a few days. Since we must poke through the kidney, sometimes there can be a little bleeding that stops on its own. As stated above, serious bleeding is rare.

How long do I keep the Nephrostomy tubes?

In short, you keep the Nephrostomy tubes as long as you need them. Sometimes, this is a matter of days or weeks until your blockage can be improved. Other people keep Nephrostomy tubes for the rest of their lives if we need to protect the kidneys but there is no other way to unblock them. If we plan for your to keep Nephrostomy tubes, we usually schedule you for a change of the tubes every 3 months (or sooner if need), so that they don’t malfunction. Many people go about their daily lives with the tubes and can carry the drainage bag strapped to their leg or back and can empty it when convenient.