Hypoglossal Nerve Stimulation for Adult OSA

First, Dr. Hensler explains the initial workup for a snoring patient. In this history, he addresses the impact snoring has on the patient’s quality of life and also assesses the environmental factors that may be responsible for the snoring, such as lack of sleep and alcohol consumption. Then, during the physical exam, he checks for anatomical reasons for snoring, such as large tonsils and a deviated septum. From the history and physical exam, he is able to classify patients into two categories: primary snorers (without sleep apnea) and snorers with sleep apnea. He recommends that all patients complaining of snoring obtain a sleep study.

Dr. Hensler then explains his criteria for choosing good hypoglossal nerve stimulator candidates. He recommends choosing patients with an Apnea Hypopnea Index (AHI) score between 15-65, a BMI of less than 31, and patients who have less than 25% of apnea attributed to mixed and central apnea. Because the CPAP machine is still the gold standard treatment for treatment of OSA, he usually only recommends this surgery to patients who have failed CPAP treatment already.

Next, Dr. Hensler explains the mechanics behind the hypoglossal nerve stimulator, which only treats obstructive sleep apnea. During the implantation surgery, the first incision is made in the right chest for placement of the processor. The processor is attached to a sensor lead that feeds into the rib cage space between the external and internal intercostal muscles. A second submandibular incision is made below the submandibular gland to place the stimulator lead. When the sensor lead in the rib cage senses the patient breathing, it relays a message to the stimulatory lead, which stimulates the protrusive branches of the hypoglossal nerve to fire and push the tongue outwards. The surgery can be performed in an outpatient setting andlasts less than 2 hours. Patients can start turning on the device before they sleep 3-5 weeks after implantation. Finally, Dr. Hensler obtains a 3 month follow up sleep study in order to monitor improvement in AHI scores.

Post-operative complications like infection and pain are possible. Dr. Hensler prescribes his patients with a short duration of narcotics for submandibular pain and a 7-day course of antibiotics to prevent infection. Because of chest involvement during surgery, a pneumothorax is another post-operative complication. A chest X-ray should always be ordered after surgery to rule out this possibility. Finally, it is important to note that patients with a hypoglossal nerve stimulator are unable to undergo MRI scans involving their right chests because of the battery in the processor.