Thrombolysis

Thrombolysis is a procedure used to break up abnormal blood clots that restrict blood flow in veins and arteries. We use two types of thrombolysis.

For chemical thrombolysis we inject a medication, such as tissue plasminogen activator (tPA) or urokinase, through a catheter to dissolve the clot.

For mechanical thrombolysis, we use a machine to break up and suction out the clot.

Procedure

The doctor will make a small incision, usually in the knee or arm, and guide a catheter (a thin tube) into the blood vessel (the vein or artery). Using live X-ray for guidance, the doctor will maneuver the catheter to the area where the clot has formed. The doctor will inject X-ray dye (called contrast) and take a series of X-rays of the clot’s placement. Then the team reviews the images and decides how best to treat the clot.

If the clot can be treated with medication, the catheter is left at the clot site and connected to a pump that will deliver medication at a precise rate, over several hours to several days. Patients receiving this treatment are carefully monitored in the intensive care unit. They return to Interventional Radiology periodically and we will X-ray the clot site, to monitor progress and determine if the treatment is working.

The catheter at the clot site is attached to a machine that sprays a saline solution onto the clot to break it up, and then suctions out the pieces of the clot. The procedure may need to be repeated. In addition to mechanical thrombolysis, we might stretch the vessel open with a balloon. (This is called angioplasty.)

Following the procedure, a bandage will be placed at the incision site and must be kept dry for 48 hours.

Anesthesia

Depending on your child’s medical history and the location of the blood clot, we will use either IV sedation or general anesthesia so that your child is asleep during the procedure.

Risks

The procedure is considered low-risk. However, potential complications include

  • bleeding (local or systemic)
  • clot dislodging and moving through the bloodstream (pulmonary emboli)
  • infection
  • allergic reaction to X-ray dye (contrast reaction)
  • injury to blood vessels

Pain

Most patients experience pain or discomfort in the area of the blood clot or catheter. This discomfort can be controlled by oral or IV pain medication.

After the Procedure

The catheter will remain in place for several days so we can evaluate the effectiveness of the treatment and repeat it if needed. To avoid disrupting the catheter’s precise placement at the clot, your child’s movement will be restricted; the arm or leg where the catheter is inserted must remain still.

When the clot is gone or no further improvement can be made, we will stop the medication and remove the catheter. Your child will have to lie quietly after for some time as we apply pressure to the catheter-entry site to prevent bleeding.

Bathing

The bandage must stay dry and in place for 48 hours. You may sponge-bathe your child during this time, as long as the bandage stays dry. After 48 hours you may remove the gauze and clear bandage and your child can take a shower or a bath, as long as the site is not immersed in water. If your child has white Steri-Strips® under the bandage, do not remove them. Do not immerse the site in water until the Steri-Strips fall off. If they have not fallen off after seven days, you may remove them.