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
The hypoglossal nerve stimulator treats obstructive sleep apnea by activating the muscles of the airway and tongue during sleep. Jonathan Knowles/Stone/Getty Images

The more common treatments of sleep apnea -- continuous positive airway pressure (CPAP) or bilevel -- 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 new device called a hypoglossal nerve stimulator might sound appealing. How does the surgery for the hypoglossal nerve stimulator, called Inspire, 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. It does not cause pain. It therefore can effectively treat obstructive sleep apnea.

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 we sleep on our backs. It may become more common as we age. 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 retracted 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 obstructive sleep apnea. 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. Individuals with upper airway resistance syndrome might also find the treatment to be helpful.

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, the wire that actually stimulates the tongue extends to the hypoglossal nerve.

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. The battery will eventually fail, requiring another surgery to swap out the implanted device (but not necessarily the wire that connects to the nerve).

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 sleep apnea. There are even other surgical options, including the pillar procedure and tracheostomy. Even something as simple as weight loss can be effective.

If you wish to learn more about the hypoglossal nerve stimulator, you will likely need to be referred to a sleep 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.

Sources:

Eastwood, PR et al. "Treating obstructive sleep apnea with hypoglossal nerve stimulation." Sleep. 2011 Nov 1;34(11):1479-86.

Eisele, DW et al. "Tongue neuromuscular and direct hypoglossal nerve stimulation for obstructive sleep apnea." Otolaryngol Clin North Am. 2003 Jun;36(3):501-10.

Kezirian, EJ et al. "Electrical stimulation of the hypoglossal nerve in the treatment of obstructive sleep apnea." Sleep Med Rev. 2010 Oct;14(5):299-305.

Oliven, A. "Treating obstructive sleep apnea with hypoglossal nerve stimulation." Curr Opin Pulm Med. 2011 Nov;17(6):419-24.

Continue Reading