Vagus nerve stimulation placement

How is the VNS device placed?

Placing a vagus nerve stimulator can be done in an outpatient setting. Here’s a quick overview of what to expect.

  • The surgery does NOT involve opening the skull or operating on the brain in any way.
  • The procedure is usually done under general anesthesia. This means you would be given medicine to make you go to sleep. You won’t be aware of what happens during the surgery.
  • The surgeon first makes an incision on the left side of the chest. It is usually above the breast, along the outer side of the chest, or under the left arm.
  • The generator is then placed under the skin. The generator is a thin, flat device. The size of the generator depends on the model. Newer models are smaller and thinner.
  • A second incision is made on the left side of the neck, usually in the folds of the skin so the scar is not seen afterwards.
  • The electrode wire from the stimulator is wound around the vagus nerve in the left side of the neck.
  • Once the electrode is placed, it is threaded or put under the skin and attached to the generator.
  • The procedure usually takes about 60 to 90 minutes.
    • Most often, the person goes home later the same day.
    • Sometimes you may need to stay overnight in the hospital for observation.

How is the VNS programmed?

videoEEG_VNS.jpg

The neurologist (or licensed professional) programs the strength and timing of the stimulation or impulses according to each person's needs. The settings can be programmed and changed by placing a wand over the generator on the left side of the chest. This wand connects to a handheld computer. A wireless programming wand is used with the SenaTivaTM model of VNS. It can also be used with older generator models, too.

  • The SenTivaTM model can be set to automatically make changes every 2 weeks without coming to the clinic. These changes can be scheduled to happen up to 7 times at home, before the person needs to come back for a visit. 
  • The device is programmed to go on (give stimulation) for a certain period (for example, 7 seconds to 30 seconds) and then to go off (stop stimulation) for another period (for example, 20 seconds to 5 minutes). The device is set to give stimulation at regular intervals during the day and night.
  • Settings (also called stimulation parameters) set by the provider also include the output current, signal frequency, and pulse width.
  • The newer models can be programmed to give stimulation automatically in response to a change in heart rate (called autostimulation). The programmer will set when the autostimulation should be given and for how long.
  • Adjusting different settings can improve how the stimulation is tolerated and how well it works.

How is the VNS magnet used?

VNS magnet swipe instructions

Each person who has a VNS device is given a set of magnets. These can be used to stop a seizure or to temporarily turn off the VNS.

When a seizure happens, the person feeling the seizure or someone who sees it, can swipe the magnet. This may help stop the seizure, make it shorter, or less intense.

To stop a seizure:

  • Swipe the magnet over the generator in the left chest area for one second.
    • Usually counting one-one thousand while it’s swiped works well to make sure you are doing it correctly.
    • Some people may not be able to use the magnet and that’s okay. Just think of the magnet as an extra way of using the VNS.
  • Each time the magnet is swiped this way, an extra burst of stimulation is given.
  • Make sure you teach others how to use the magnet and make it a routine part of your seizure first aid plans.

To turn the VNS device off:

  • If side effects from the stimulation are a problem, you can tape the magnet over the generator in the left chest area. This will turn off the stimulation temporarily.
  • As long as the magnet is kept over the generator, no stimulation will be given.
  • Once the magnet is removed, the generator will give stimulation again.
  • Talk to your health care team about when to use the magnet to turn off stimulation.
    • Sometimes people use the magnet to turn the VNS device off before they have a test or surgery.
    • Other times people may turn it off during certain activities.

What are the most common side effects of vagus nerve stimulation?

Side effects of VNS Therapy® can be separated into two kinds: 1) those related to the placement of the device, and 2) side effects that may happen with stimulation.

Surgery Side Effects

  • After surgery, there may be some discomfort or pain around the wounds for a few days.
  • There is a small risk of infection of the wounds.
    • Everyone should be given clear instructions on how to take care of the wound and dressings after surgery. If someone lives alone or needs help checking the dressings, ask for a visiting nurse to check on the wounds during the first 1-2 weeks.
    • Any signs of infection after surgery (such as too much redness, drainage, bleeding from the wound, or fever) should be reported to the surgeon right away. If needed, an antibiotic will be given.
    • If an infection is not treated promptly, the device may need to be removed.
  • There is a very low risk of a nerve to the vocal cords being affected or stretched during surgery. If this happens, the vocal cord on the side of surgery may not work normally. A person’s voice may be hoarse and soft. Often, the voice may get better on its own over weeks to months. An ENT (ears nose and throat) specialist may be able to help these symptoms too.
  • As with any surgery, a very small number of people may have trouble with anesthesia. Talk to your doctor if you have had any problems with other surgeries.

Side Effects of Programming and Stimulation

The most common side effects seen with stimulation include:

  • Hoarseness or change in speech pattern
  • Cough
  • Funny feeling in the throat
  • Tightness or pain in the throat or neck area
  • Difficulty swallowing
  • Headache
  • Difficulty breathing (often a sensation of difficulty catching your breath)
  • Rarely, indigestion or burping may happen

Side effects may happen when the programming is first started. The feelings go away usually in a few hours or days as the person gets used to the settings. They may come back again temporarily when the settings are increased.

  • If side effects happen, tell the doctor or nurse programming the device. Settings can be adjusted so the symptoms don’t bother you.
  • In most people, side effects go away over time.
  • If side effects get in the way of certain activities, the stimulation can be turned off temporarily by taping the magnet over the generator. After the activity is done, remove the magnet and the stimulation will go back to its usual pattern. Examples of when this is done may include:
    • Hoarseness or cough getting in the way of singing or public speaking
    • Difficulty catching your breath when exercising

Does the VNS device ever need to be removed or replaced?

  • The generator has a battery inside that usually lasts a number of years.
  • When the battery wears down, the generator will need to be replaced during a new procedure.
  • The procedure to replace the battery usually takes less than an hour. The person usually goes home the same day.
  • After replacing a generator, talk to your epilepsy team about when it will be programmed. You may need to be seen more frequently for a few weeks or month until settings are back to usual for you.
  • If a person feels VNS does not work well enough for them, they can have the settings turned off. The device does not need to be removed. The generator can be removed completely if needed, but sometimes the entire lead cannot be removed.

Are there other safety concerns with the VNS Therapy®?

As with any treatment, people should be aware of any safety concerns and what steps to take to prevent problems. When a person has the VNS device put in, they should be given a manual that describes vagus nerve stimulation and safety information. If you do not receive one, contact LivaNova at 888-867-7846 or visit vnstherapy.com.

MRI (magnetic resonance imaging)

  • People with a VNS device can have an MRI, but certain precautions need to be taken.
  • Depending on the VNS device implanted, you may need to use a special MRI machine. Talk to your epilepsy team before booking any MRI and make sure the proper machine and type of MRI is booked.
  • The VNS should be turned off before the MRI. Make an appointment with your epilepsy team to have this done before going to the MRI room.
  • After the MRI, the VNS can be turned back on.
  • Read more about MRI Safety from LivaNova.

Other Procedures

People who need other procedures or other types of surgery may need to follow special precautions.

  • Ask your epilepsy team to check and make sure of any safety concerns for other medical tests or surgeries.
  • Depending on the location on your body or type of surgery or test, you may need to have the VNS turned off first. Make sure you set up appointments with your epilepsy team to do this.

Resources

Find an epilepsy specialist to help you explore this, and other, treatment options.

The VNS Therapy® implant devices are built by LivaNova (formerly Cyberonics, Inc.). Additional information for patients and physicians is available at their website vnstherapy.com.

Device images on this page included with permission from LivaNova. Patient and doctor image provided courtesy for Dr. Matthew Hoerth.

Authored By: 
Patricia O. Shafer RN, MN and Patricia M. Dean ARNP, MSN, CNRN
Authored Date: 
03/2018
Reviewed By: 
Joseph I. Sirven MD
on: 
Monday, March 12, 2018