For years, one of the primary ways to treat patients with obstructive sleep apnea was through the use of a device known as a continuous positive airway pressure – or CPAP – machine, which forces air through the nasal passages to interrupt dangerous pauses in breathing while sleeping. For people can't tolerate the machine, a new chest implant that sends electrical pulses to a nerve in the tongue promises healthier rest, as reported in a new University of Pennsylvania (U Penn) study.
Obstructive sleep apnea (OSA) is a condition wherein the muscles in the throat relax so much during sleep that they block the airway and cause breathing to intermittently stop and start through the night, making it impossible to get a good night's rest. The condition can strain the cardiovascular system due to restricted oxygen intake, and can cause general daily fatigue according to the Mayo Clinic. Some cases of OSA can be cured with a mouthpiece or the CPAP machine, but in other cases, more serious intervention is called for – which is where the implant comes in.
First clinically trialed in 2010, and approved by the FDA in April 2014, the implant is from a company called Inspire and is basically a pacemaker for the tongue.
"Inspire therapy is made of three fully implanted components," a company representative told Gizmag. "The battery, about the size of an Oreo cookie, is implanted under the skin just below your right collar bone. In addition, one lead is placed under your chin to stimulate the hypoglossal nerve and the other is near your ribs to monitor your breathing."
The monitoring lead determines when a patient's breathing is off and, by stimulating the hypoglossal nerve – the nerve responsible for the tongue's movements – the airway is kept open.
The device is turned on and off with a user-operated remote control and it doesn't start working immediately, so that patients have a chance to fall asleep before their hypoglossal starts getting zapped. Also, according to Richard Schwab, co-medical director of the Penn Sleep Center, the device isn't activated until one month after the simple outpatient surgery used to install it, to give patients time to heal. Schwab also told us that the Inspire's batteries last for between eight to 11 years and that the unit needs to be replaced via surgery after that.
In the U Penn study, which will be presented this month at SLEEP 2016, the 30th annual meeting of the Associated Professional Sleep Societies LLC, 20 implants were carried out between January 2015 and March 2016. Thanks to the device, pauses in breathing dropped by 84 percent and the measure of the lowest blood oxygen level during sleep rose from 79 percent to 90 percent.
"Considering that sleep apnea can lead to high blood pressure, heart attack, stroke, and other serious health problems, it is critically important that we study devices that may serve as another option instead of CPAP to treat patients with sleep apnea," says Schwab. "There is no perfect treatment option for obstructive sleep apnea, but our preliminary data suggest that hypoglossal nerve stimulation can effectively treat patients with sleep apnea who are unable to tolerate CPAP."