Sleep apnea syndrome is divided into three types: 1, obstructive sleep apnea syndrome; 2, central sleep apnea syndrome; 3, mixed sleep apnea syndrome. Obstructive sleep apnea syndrome is in the sleep of the oral and nasal airflow stops, while the thoracic and abdominal breathing action still exists, mainly due to the obstruction or narrowing of the upper respiratory tract during sleep, so from the anterior nostrils to the upper tracheal opening of any part of the narrowing or obstruction, can lead to apnea, is the most common sleep apnea syndrome, central sleep apnea syndrome refers to the oral and nasal airflow and thoracic and abdominal breathing action stops simultaneously, mainly due to the central nervous system, and the central nervous system, and the central nervous system, and the central nervous system, and the central nervous system, and the central nervous system. Central sleep apnea syndrome refers to the simultaneous cessation of oro-nasal airflow and thoracic and abdominal breathing movements during sleep and is mainly due to dysfunction of the respiratory center of the central nervous system. Central sleep apnea syndrome is mainly caused by neurological disorders, such as spinal cord lesions or encephalitis, but also includes muscular disorders or apnea caused by heart failure. Mixed sleep apnea syndrome is the coexistence of both obstructive and central, beginning with central apnea and subsequently manifesting as obstructive sleep apnea.