Hypoglossal Nerve Stimulator Treatment for Sleep Apnea

Implanted Device Activates Tongue Muscles to Open Airway

The hypoglossal nerve stimulator treats obstructive sleep apnea by activating the muscles of the airway and tongue during sleep
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The more common treatments of obstructive sleep apneacontinuous positive airway pressure (CPAP) or bilevel therapy—may be difficult to tolerate. As the condition can have serious, and even fatal, consequences, you may be motivated to seek out alternative options. Surgery may seem like a desirable option and the use of a device called a hypoglossal nerve stimulator might sound appealing. How does the surgery for the hypoglossal nerve stimulator, called Inspire in the United States, treat obstructive sleep apnea? Learn how an implanted tongue pacemaker device works.

What Is the Hypoglossal Nerve Stimulator?

The hypoglossal nerve stimulator is an implanted medical device that works to reduce the occurrence of obstructive sleep apnea by electrically stimulating the hypoglossal nerve to the tongue. This stimulation activates the muscles of the tongue, increasing the tone and moving it forward, away from the back of the airway. The stimulation does not cause pain.

It can effectively treat moderate to severe obstructive sleep apnea. This means that at baseline there are more than 15 partial or complete blockages of the throat per hour of sleep based on testing. If treatment with CPAP or bilevel therapy is not tolerated, this may be a reason to consider the hypoglossal nerve stimulator.

How Does the Hypoglossal Nerve Stimulator Work?

Obstructive sleep apnea is characterized by blockage of the upper airway (typically the back of the mouth or throat). When this obstruction occurs, the airway completely collapses and normal breathing during sleep cannot occur.

There are certain conditions that might predispose someone to this sort of obstruction. The airway may collapse due to a loss of muscle tone that occurs as part of rapid eye movement (REM) sleep. It may be more prevalent when sleeping on the back. It may become more common with aging. It is certainly more likely among the overweight and obese. The use of alcohol and medications that relax muscles might also predispose toward it. In addition, there are parts of our anatomy that might lead to sleep apnea. For example, a large tongue (called macroglossia) or a small or recessed lower jaw (called retrognathia) may lead to airway obstruction.

The hypoglossal nerve stimulator is meant to open the airway by moving the tongue forward during sleep. When it is activated, it electrically stimulates the hypoglossal nerve to the tongue. This causes a muscle contraction that brings the tongue forward. The timing of this stimulation may be constant during sleep or synchronized to correspond with your breathing pattern.

What Conditions Does It Treat?

The hypoglossal nerve stimulator is currently being used for the treatment of moderate to severe obstructive sleep apnea in adults. The body mass index (BMI) must be less than 32 (meaning morbidly obese people are excluded). Sleep endoscopy is used to ensure that there is not a concentric (complete) collapse of the airway as these individuals would not respond as well to the treatment. It would not be helpful in individuals with central sleep apnea. It might also improve snoring, but it is not approved solely to treat this condition. 

Surgical Procedure for Placement

The hypoglossal nerve stimulator must be placed surgically. The main part of the device is implanted under the skin of the upper chest wall, much like a pacemaker. This component includes the battery as well as the part that generates the electrical stimulation. From here, there is a wire that actually stimulates the tongue extends to the hypoglossal nerve. A second wire is directed to the chest wall to detect the breathing pattern.

The Risks of the Hypoglossal Nerve Stimulator

The most common risks with the use of a hypoglossal nerve stimulator are those associated with the placement surgery itself. If your underlying health and medical conditions put you at higher risk for any surgery, then this might not be a good option for you. As with any surgery, there is a risk of bleeding and infection.

The hypoglossal nerve stimulator could potentially dysfunction. This might mean that it stops working entirely. It may also fire or activate inappropriately, leading to discomfort during wakefulness. The battery will eventually fail, requiring another surgery to swap out the implanted device (but not necessarily the wires that connects to the nerve or chest wall).

Alternatives to the Hypoglossal Nerve Stimulator

If you decide that a hypoglossal nerve stimulator is not for you, you may wish to explore other treatment options. Certainly, CPAP is the first-line treatment and you may learn to tolerate it better by following some basic guidelines. It may be as simple as learning how to choose a mask. Some people prefer the use of a dental device, which can reposition the jaw and alleviate mild to moderate obstructive sleep apnea. There are even other surgical options, including the pillar procedure and tracheostomy. Even something as simple as weight loss can be effective.

A Word From Verywell

If you wish to learn more about the hypoglossal nerve stimulator, you will likely need to be referred to a board-certified sleep or ear, nose, and throat (ENT) specialist who has an expertise in the device. It may not yet be available in all regions as it is still a newer treatment method.

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Article Sources
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