Hypoglossal nerve stimulation

What is a hypoglossal nerve stimulator?

Hypoglossal nerve stimulation (HNS) is a new technology that’s used in the treatment of moderate to severe cases of obstructive sleep apnoea (OSA), a condition where breathing stops and starts during sleep.

It uses an implanted upper airway stimulation device (Inspire or Genio devices are currently used) to deliver a gentle pulse to the hypoglossal nerve(s), which pushes the tongue forward slightly, helping to keep the airway open during sleep. 

At OneWelbeck, our ENT specialists deliver this treatment as a daycase surgery, ensuring you receive the treatment you need quickly and with as little disruption as possible.

Why would you have a hypoglossal nerve stimulator fitted?

If left untreated, OSA can lead to serious health problems, such as heart disease.

Some cases of the condition may be successfully treated by making lifestyle changes, but many people will need to use a CPAP machine, which helps to keep the airways open while sleeping.

Although CPAP therapy is the gold standard in OSA treatment, many patients find it uncomfortable to wear and sleep in a CPAP mask, leading to reduced use of the machine. Hypoglossal nerve stimulation (HNS) is a non-disruptive and highly effective alternative treatment for those who cannot tolerate using a CPAP machine.

While the treatment isn’t suitable for everyone, hypoglossal nerve stimulation has been found to be a very helpful and effective solution for those with moderate to severe sleep apnoea, where other treatments have not been effective or tolerable.

Your consultant will discuss whether hypoglossal nerve stimulation is appropriate for you. Generally, these implants are suitable for people who are not significantly overweight (have a BMI less than 35).

At an initial consultation, your ENT specialist will assess whether you’re a good candidate for hypoglossal nerve stimulation treatment. 

Before recommending it, they will evaluate your BMI and tolerance of CPAP therapy as well as rule out other sleep-related issues such as insomnia, parasomnia and restless leg syndrome.

If a sleep study has not already been conducted, this may also need to be done, which, depending on your symptoms, may involve a NOX T3 test, polysomnogram (PSG) or a drug-induced sleep endoscopy (DISE).

What does hypoglossal nerve stimulator implantation involve?

At OneWelbeck, the relevant device (Inspire or Genio) is implanted under general anaesthetic. The procedure is performed in our outpatient centre, taking two to three hours to complete.

If using the Inspire implant, your surgeon will make two small incisions and place the device under the skin in the chest, below the collarbone. A breath-sensing lead is then run from the device, up the neck and is attached to the hypoglossal nerves. Once activated, you switch the device on each night before sleep and off upon waking using a small remote control.

If using the Genio implant, a small incision is made and the device is placed under the chin on the hypoglossal nerves. In this case, an external battery and activation chip need to be applied under the chin with a sticky patch each night.

What happens after the surgery?

Most patients return home on the same day as the surgery and can return to non-strenuous activities after a few days. 

It’s normal to experience soreness and slight swelling after the procedure, and over-the-counter pain medications can help manage this.

Healing needs to take place before the device can be switched on, which usually takes around a month. Your consultant will check your wounds at a follow-up appointment, and if they have healed, the device will be activated. 

Your consultant will monitor your health and the effectiveness of the therapy by conducting a second sleep study. Long term, you may have subsequent follow-up appointments, with or without sleep studies.

Are there any risks associated with hypoglossal nerve stimulator implantation?

As with any procedure, hypoglossal nerve stimulator implantation carries some risks. These include:

• Infection
• Bleeding
• Nerve damage
• Device malfunction requiring further surgery
• Pain
• Numbness
• Inflammation at the implant site 
• Pneumothorax (in rare cases)
• Pleural effusion (in rare cases)