[Abstract] OBJECTIVE: To investigate the efficacy of adenotonsillectomy and pharyngoplasty in the treatment of obstructive sleep apnea hypoventilation syndrome (OSAHS) in children. METHODS: Adenotonsillectomy and pharyngoplasty were performed in 94 cases and tonsillectomy and pharyngoplasty in 68 cases of 162 children with OSAHS, and polysomnography (PSG) was performed six months after surgery. Results: All children had significant improvement in sleep snoring, breath-holding, open-mouth breathing, and inefficient learning after surgery. The efficacy was evaluated: 126 cases (77.78%) were cured, 27 cases (16.6%) were effective, 9 cases (5.56%) were effective, and 0 cases were ineffective, with an overall efficiency of 100%. Conclusion: Adenotonsillectomy and pharyngoplasty can effectively relieve the stenosis or obstruction of oropharynx and nasopharynx in children, improve the ventilation of upper airway of children, and make the airflow smooth during sleep, which is an effective means to treat OSAHS in children. Obstructive sleep apnea hypoventilation syndrome in children mainly manifests clinically as snoring, breath-holding, open-mouth breathing and urine loss at night, mental inactivity, head boredom, hyperactivity and inattention during the day, and even hypoxemia and increased pulmonary artery vascular pressure, causing serious diseases such as pulmonary heart disease, which seriously affects the growth and development of children and their life and learning, and therefore is receiving more and more attention. The main cause of OSAHS in children is adenoid and tonsillar hypertrophy. From March 2006 to October 2008, 162 children with OSAHS were treated with adenoidectomy and/or tonsillectomy and pharyngoplasty in our hospital, and satisfactory results were achieved, which are summarized below. 1. Data and methods 1.1 Clinical data Among the 162 children, 93 were male and 69 were female; their ages ranged from 5 to 14 years old, with an average of 8.6 years; the duration of the disease ranged from 6 months to 8 years, with an average of 3.5 years. All children had symptoms such as snoring, breath-holding, open-mouth breathing, enuresis, daytime dysphoria, dull head, hyperactivity, and inattention, etc. All children were diagnosed with OSAHS by PSG examination, except for obesity, enlarged tongue, small jaw, and deviated nasal septum. All children were examined by pharyngeal examination, nasal endoscopy or fiberoptic nasopharyngoscopy, and lateral nasopharyngeal radiographs to determine the size of tonsils and adenoids. The results were: 58 cases of simple tonsillar hypertrophy and 104 cases of simultaneous tonsillar and adenoid hypertrophy. The diagnostic criteria for tonsillar hypertrophy were bilateral tonsils of degree II or higher or unilateral degree III hypertrophy. The diagnostic criteria for adenoid hypertrophy were that the ratio of adenoid thickness to nasopharyngeal ventilation width was >0.70 on lateral nasopharyngeal radiographs, and that nasal endoscopy or fiberoptic nasopharyngoscopy showed adenoids blocking the posterior nostril by >50% [1]. 1.2 Polysomnography (PSG) Sleep respiratory monitoring was performed before and six months after surgery, and the monitoring time was at least 7 h. The monitoring content included EEG, electrooculogram, oral and nasal airflow, chest and abdominal movements, oxygen saturation, heart rate, etc. 1.3 Diagnostic and efficacy assessment criteria Refer to the diagnosis and efficacy assessment criteria of OSAHS in children in the Urumqi meeting in August 2006 [2]. There were 65 mild cases, 76 moderate cases and 21 severe cases in this group. 1.4 Treatment All procedures were performed under general intravenous anesthesia with tracheal intubation. In cases of tonsillar hypertrophy, the tonsils were removed by peeling method, and after hemostasis, the palatopharyngeal arch and palatoglossal arch were sutured in alignment with 3 – 4 stitches for pharyngeal molding. In the case of combined adenoid hypertrophy, after the above procedure, the bilateral nasal mucosa was contracted with a cotton pad containing 1‰ epinephrine, entered through the left anterior nostril with a 2-mm thin tube, withdrawn from the oral cavity and tied with a knot to pull up the soft palate to facilitate the operation of adenoidectomy. 2. Results At 1-2 years of follow-up, the children showed significant improvement in sleep snoring, breath-holding, open-mouth breathing, and inefficient learning, as well as significant increase in height and significant improvement in inattention and hyperactivity. When the PSG was reviewed in all cases 6 months after surgery, there was a significant decrease in AI, AHI, longest apnea time and longest hypoventilation time, and a significant increase in minimum oxygen saturation. Evaluation of efficacy: 126 cases (77.78%) were cured, 27 cases (16.67%) were effective, 9 cases (5.56%) were effective, and 0 cases were ineffective, with an overall efficiency of 100%. Among the effective and efficient 36 cases, 19 cases were combined with chronic rhinosinusitis and were expected to be cured by nasal treatment. The operation went smoothly and no complications such as haemorrhage, infection and acute respiratory obstruction occurred in all cases. 3. Discussion Children are in an important period of physical and intellectual development, and OSAHS can have serious adverse effects on their growth and development and life and learning. Adenoid hypertrophy and/or tonsillar hypertrophy are the most common causes of OSAHS in children, and adenoidectomy and tonsillectomy are the main surgical means to treat OSAHS in children. Since children do not cooperate well with surgery. The reason why we choose children over 5 years old for surgery is that children under 5 years old cannot cooperate with postoperative stitch removal. Children with adenoid hypertrophy are often combined with chronic rhinosinusitis, and further postoperative treatment is needed to relieve nasal obstruction in order to improve the cure rate.