Hypoglossal nerve stimulation [HGNS] for Obstructive Sleep Apnea [OSA] treatment – a review

Obstructive sleep apnea (OSA) is characterized by recurrent periods of upper airway obstruction (hypopneas and apneas) during sleep. It leads to repeated oxyhemoglobin desaturations, nocturnal hypercapnia, and arousals. Common symptoms include loud snoring with breathing interruptions. Excessive daytime sleepiness and cognitive impairment occur. Obstructive sleep apnea is a major cause of morbidity and mortality in Western society. Its association with an increased risk of development and progression of neurocognitive, metabolic, cardiovascular and oncologic diseases and complications is well described. The significant factor in OSA pathogenesis is reduced muscle tone in the tongue and upper airway. In the recent years, devices providing neurostimulation of the hypoglossal nerve (HGNS) were developed as an alternative for noncompliant CPAP (continuous positive airway pressure) patients. Clinical trials suggest that electrical stimulation of the hypoglossal nerve is effective. This is considered to be one of the targets of neurostimulation in the treatment of obstructive sleep apnea (OSA).