Inspire Hypoglossal Nerve and Upper Airway Stimulator for Sleep Apnea

Implanted device improves moderate to severe sleep apnea


If you have obstructive sleep apnea, you may be interested in exploring surgical treatment options. One such option is the hypoglossal nerve stimulator called Inspire. What is Inspire? Who should consider using it and what are the side effects? Learn about the Inspire upper airway stimulator and whether it might be the right therapy for you.

Candidates for Inspire Placement

The Inspire stimulator is a surgically implanted device that activates the hypoglossal nerve to tighten the muscles of the tongue and upper airway during sleep, improving airflow and reducing sleep apnea. It is approved for use by those with moderate to severe obstructive sleep apnea (apnea-hypopnea index or AHI >15) who are not compliant with CPAP therapy. It is indicated for those with a body-mass index (BMI) less than 32, excluding those with morbid obesity.

There are a few relative contraindications to the use of Inspire therapy. If the obstruction contributing to sleep apnea is occurring within the nose, due to allergies or a deviated nasal septum, it will be ineffective. Similarly, certain skeletal anatomy (such as a small or recessed lower jaw) may be a reason to not pursue the treatment. If tonsils are enlarged, surgery targeting these tissues may be more appropriate. Certain neuromuscular conditions that affect the ability to swallow or contribute to slurred speech may also be a contraindication. If frequent MRIs are needed for other medical conditions, the device is not safe for use with these studies. The treatment is not approved for use in children.

Describing the Surgery Required for the Placement of the Inspire Stimulator

Inspire must be placed during surgery with general anesthesia in an operating room. Preceding the placement, another procedure called drug-induced sleep endoscopy may be performed to assess your airway anatomy and whether the device is likely to be effective. Some patients, called non-responders, do not benefit from the treatment. This is more likely if the airway seems to completely collapse from all sides during the endoscopy procedure.

Once you are determined to be a candidate, a specially trained ear, nose, and throat (ENT) specialist performs the surgery as an outpatient procedure. The stimulation wire is placed leading to the hypoglossal nerve and wraps one of its distal branches. A second sensing lead is placed along the rib cage to detect breathing so the tongue muscle and airway can be stimulated at the proper time as breath is drawn in. Finally, the stimulator itself is placed within the right upper chest wall and connected to the sensors. The entire procedure takes about 2 hours.

After the surgery, patients usually go home if there have not been any complications. Most do not require the use of narcotic pain medications. It is recommended that strenuous activity be avoided for 2-3 weeks following the surgery. A regular diet can be consumed without any necessary modifications.

The Effectiveness of Inspire and Required Follow-up Evaluation

Inspire airway stimulation is a relatively effective treatment for moderate to severe obstructive sleep apnea when CPAP is not tolerated. Studies have shown that at 12 months it reduces the AHI from 29.3 to 9.0 events per hour, on average, representing a 68% reduction. It should be noted that the residual AHI still represents mild sleep apnea. This may improve as the therapy is optimized and appropriate candidates are identified. Scores on the Epworth sleepiness scale improved from 11 to 6 with treatment, suggesting a reduction in daytime sleepiness. When the device is turned off, sleep apnea mostly returns.

There are few complications to the placement of the Inspire device. About 25% of patients complained of relatively modest pain. About 1/3 of patients complained of tongue discomfort or abrasion, but this seemed to resolve in time. About 1% developed skin infection or irritation (cellulitis) from the surgery and another 1% had to have another surgery to correct the device placement.

After the surgery is completed, patients return to see the surgeon for a post-operative check at 7-10 days. The device is turned on at 1 month. It is recommended to have an in-center sleep study at 2 months to assess its effectiveness and adjust the settings.

Once placed, the Inspire stimulator can be activated before going to sleep. There is usually a delay of 30 minutes before the stimulation begins. If you wake at night, the device can be paused. It is often set to turn off after 8 hours.

How much does the treatment cost? The Inspire device presently costs about $30,000 to $40,000 to place, including the expenses associated with surgery, and the replacement of the battery can cost another $17,000. These costs may be covered by insurance.

If you are interested in learning more about the Inspire upper airway stimulator as a treatment option for you, contact a provider near you to discuss this option. Sleep specialists can also provide information about alternative treatments, including the optimized use of CPAP, oral appliances, and other therapies.

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