Sodium Amytal Test/WADA Test
A Sodium Amytal or WADA test is needed as part of your work-up for epilepsy surgery. This test helps us locate which side of your brain supports language and looks at the blood vessels of your brain. It tries to predict if the side of the brain that doesn't have surgery can support memory and language functions. The purpose of this handout is to help explain what will happen before, during, and after the test. You may find it helpful to bring this handout with you when you come for the test.
If you are allergic to shellfish (shrimp, lobster, etc.) or have ever had a rash from iodine put on your skin or into your arteries or veins during other tests, please call our office right away: (608) 263-9578.
About the Test
This test is done as part of a special X-ray called a cerebral angiogram. This X-ray uses dye to show the blood vessels in the brain. Testing is done by doctors called neuroradiologists.
Before You Come to the Hospital
You or your child will need to have a physical exam done within 30 days of the scheduled WADA. This can be done by your local doctor. Along with the exam, some blood work will be done. We need the lab results no later than 1 week before the WADA.
Certain medicines can affect your body’s ability to clot. Please be sure your doctor is aware of the medicines you are taking before your angiogram with WADA testing is scheduled. The only medicine that affects clotting that must be stopped before the angiogram is Coumadin® (warfarin). Sometimes, patients may need to be hospitalized for a few days before the test if they are taking Coumadin® so we can safely switch you over to a different blood thinner. Do not stop taking Coumadin® without first talking with your doctor.
Tell us about your allergies. Let us know if you are allergic to x-ray dyes, IV contrast, iodine, antibiotics, anesthetic agents, latex, or any other medicines that you may have taken before.
Let us know if you have sleep apnea or use a CPAP machine at night when you sleep. This is important to know so we can safely use medicines that make you sleepy during the procedure.
Let us know if you have had any fever or pain in the week before your test. We also need to know if you have had any procedures or tests in the month before your angiogram.
Make plans to have someone drive you home after the test. You CANNOT drive for 24 hours after the test. Plan to have someone stay with you that night, just in case any problems occur and you need care right away.
On the Day of the Test
Do not eat on the morning of the test! You should take your seizure medicine with one or two glasses of water or fruit juice before 6 a.m. on the morning of the test. Do not take any other medicine until you talk to the doctor on the day of the test. Bring a one-day supply of your medicines with you.
You must be at the hospital by 7:30 a.m. Please take the Atrium elevators to the 3rd floor Radiology reception desk to check in. For anyone under 12 years old: Please report to the Pediatric Day Treatment Center at the American Family Children’s Hospital. You will be asked to change into a hospital gown. An IV will be started in one of your arms so that we can give you extra fluids during the test. One of the doctors will meet you in the Radiology prep area and talk to you about the test itself. The neuroradiologist will tell you about the procedure in more detail, explain risks and benefits, and obtain your informed consent. Feel free to ask questions and talk about your concerns at this time.
Next, the EEG (Electro EncephaloGraphy) technicians will come and place EEG electrodes (wires) on your scalp so that we can record your brainwaves during the test.
During the Test
Around 8:30 a.m. you will be helped onto a cart. A nurse will take you to the X-ray room. Your family may wait in the waiting area. When you arrive, you will move onto the table where the test takes place. From now on you must lie very still!
When the test begins, the doctor will numb one side of your groin and put a small catheter (IV tube) into an artery in your groin. Only one needle puncture is needed to test both sides of the brain. Using an X-ray camera called a fluoroscope, the IV is threaded up to one of the arteries in your neck (carotid) that supplies blood to the brain. Next, a dye is pumped into the IV that outlines the blood vessels on that side of your brain.
If the doctor decides that the blood vessels are working well, a drug called sodium amytal is put into the IV. The drug will put one side of your brain to sleep; the other side of your brain will be awake and able to answer questions.
The doctor will ask you questions. Sometimes people get frustrated during this part of the test, but this goes away when the medicine wears off. When the test is over for that side of your brain, the X-ray doctor will move the IV to the other carotid artery. Then the test will be repeated on the other side. The entire test lasts about 90 minutes.
After the Test
When the IV has been taken out, the doctor will hold pressure on your groin for at least 10 minutes to help the artery seal the puncture. You will be lifted onto the cart and taken back to the recovery area. There will be a bandage on your groin. You will not be allowed to move your leg on that side for anywhere between 3 and 6 hours. The nurses will check your blood pressure and pulse often. They will also check your groin to make sure there is no bleeding, bruising, or swelling.
You may eat as soon as you feel like it after the test. You should drink extra fluids to help flush the dye from your body. You will have to use a bedpan or urinal for the first few hours after the test. A nurse will help you to the bathroom when you are allowed to get up later. If there are no problems, like bleeding or swelling, you may go home the same day.
The team will review the results of the test and decide about your need for surgery. The epilepsy doctor or nurse will call you about the decision in 2 to 3 weeks. You will have a visit in the epilepsy clinic about 4 weeks after your test.
Keep the band-aid over the groin site for the next two days. Drink 10-20 glasses of fluid the first 24 hours. If bleeding occurs at the puncture site, apply direct pressure and go to the nearest emergency room. You should not drink any alcohol during this time.
When to Call the Doctor
- The puncture site becomes red and/or hot.
- Any yellow or green drainage comes from the site.
- Swelling occurs at the site.
- Your temperature goes over 100 F by mouth.
- A large bruise appears under or around the site.
- Severe pain or spasm occurs in the leg.
- Numbness or tingling occurs in foot or leg.
- Itching, hives or rash appears.
For questions after the test, call (608) 262-0486. This will give you the paging operator. Ask for the neuroradiologist on call. Give the operator your name and phone number with the area code. The doctor will call you back.
If you live out of the area, please call 1-800-323-8942.
The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.
Last Updated: 09/21/2011
Copyright © 09/21/2011 University of Wisconsin Hospitals and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#4490
Print Health Fact For You