People diagnosed with obstructive sleep apnea, or OSA, experience frequent disruptions of breathing while asleep. Those disruptions can range in frequency from five times in an hour for mild sleep apnea to 30 times or more for severe sleep apnea. In other words, a person with severe OSA stops and starts breathing at least every two minutes within an hour.

Left, air passes through the airway without obstruction.
Right, in obstructive sleep apnea, the airway is blocked.
Photos courtesy of Shutterstock

“Apnea occurs when the soft tissues in the back of the throat collapse and block or narrow the airway during sleep,” explains Brendan Lucey, MD, Washington University neurologist at Barnes-Jewish Hospital and head of the university’s Sleep Medicine Center. “Each time that happens, the body arouses briefly to allow muscle tone to increase, which reopens the airway and allows breathing. These small arousals usually don’t bring someone fully awake, but they disrupt the normal sleep cycle needed for restorative sleep.”

Over time, untreated OSA may cause significant complications, including high blood pressure, cardiovascular disease, coronary artery disease, type 2 diabetes, depression and sleepiness-related accidents. Risk factors for the condition include: excess weight, large neck circumference, snoring, daytime sleepiness, inherited narrowed airway, being male, being older, a family history of OSA, smoking, nasal congestion, existing medical conditions and use of alcohol, sedatives or tranquilizers.

“Once we determine a person has risk factors for OSA, we conduct a sleep study, either an at-homestudy that detects the number of breathing disruptions per hour of monitoring time, or an in-lab study monitoring disruptions plus sleep and respiratory function, leg movement, heart rate and oxygen saturation,” says Lucey. “Positive results for either of these tests mean we can start treatment immediately. In cases where the at-home study comes back negative, we follow up with a lab study to confirm those results.”

Most patients with OSA receive treatment in the form of continuous positive airway pressure, commonly known as CPAP. This involves the use of a sleep apnea machine that provides a gentle and constant flow of pressurized air through a CPAP mask and hose that keeps the airway open during sleep. The amount of air pressure is determined by each individual’s needs.

THE LATEST TREATMENT FOR OBSTRUCTIVE SLEEP APNEA INVOLVES SURGERY TO IMPLANT A DEVICE
CALLED A HYPOGLOSSAL NERVE STIMULATOR

“CPAP is an effective treatment that doesn’t involve drugs or surgical intervention Most patients become accustomed to the CPAP mask and report greatly improved sleep,” says Lucey. “Patients with low to moderate OSA may choose to instead have a mandibular advancement device made by a dentist experienced in dental sleep medicine. This oral appliance pulls the lower jaw forward, creating additional space in the back of the throat and upper airway.”

A device to control moderate to severe obstructive sleep apnea functions much like a heart pacemaker. Image courtesy of Inspire

The latest treatment for OSA involves surgery to implant a device called a hypoglossal nerve stimulator, which is similar in appearance to the heart pacemaker used to regulate a person’s heartbeat.

“The device is a breath pacemaker that is implanted in a pocket created in a person’s chest wall under the collar bone,” says Ryan Jackson, MD, a Washington University otolaryngologist at Barnes-Jewish Hospital who performs this type of surgery. “The implant has two wires: One of them is placed in the intercostal muscles of the rib, and the other is connected to the hypoglossal nerve at the back of the tongue. Every time a person breathes, the wire in the rib muscle sends a signal through the pacemaker to the wire connected to the hypoglossal nerve, causing those muscles to conract and push the tongue outward and away from the back of the throat, thus creating more space to breathe.”

Once the pacemaker is in place, it is turned on and off using a remote. The implanted device’s battery lasts for about 10 years before it needs to be replaced.

This surgical treatment is available to people with moderate to severe OSA—defined as between 15 and 65 breathing disruptions an hour—who have problems tolerating or adhering to CPAP therapy. In addition, candidates must be 22 years of age or older and have a body mass index (BMI) of no more than 33. People with neuromuscular diseases such as amyotrophic lateral sclerosis (ALS) or severe cardiopulmonary disease are not eligible for the surgery.

During the placement procedure, Jackson performs a drug-induced sleep endoscopy, which mimics sleep and allows him to insert a small camera or endoscope into the upper airway to evaluate how it is collapsing. A person with an airway that collapses concentrically, meaning all sides collapse at the same time, is not a candidate for the treatment. If Jackson finds an interior/posterior collapse—from front to back—he will implant the device.

“Usually, patients go home the same day after the implantation surgery. They experience a bit of soreness and swelling in the muscles under the jaw, which lasts for a week or two. They may go back to normal activity in about two weeks,” says Jackson.

A month after surgery, patients return to have the pacemaker activated; within about three months they return again to complete a sleep study and have adjustments made as needed.

“Ninety-five percent of the people we treat are highly satisfied with the surgery,” says Jackson. “They no longer need the CPAP machine, they sleep better, and many of them experience an improvement in their snoring. For those who meet the criteria, the implanted device is an efficient and effective treatment for their OSA.”