title: Tonsil size and body mass index are important factors for efficacy of simple tonsillectomy in obstructive sleep apnoea syndrome.
abstract: OBJECTIVE
  To evaluate the efficacy of simple tonsillectomy to treat obstructive sleep apnoea syndrome (OSAS) in adults.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Tertiary referral centre.
  
  
  METHODS
  Thirty patients (28 males) underwent simple tonsillectomy under general anaesthesia. The patients' mean age was 33.2 +/- 6.8 years and body mass index was 30.7 +/- 6.0 kg/m2. Seven patients (23%) were classified with grade 4, 16 patients (53%) with grade 3, and seven patients (23%) with grade 2 according to the tonsil size of Friedman's classification.
  
  
  METHODS
  The number of apnoea episodes per hour (apnoea index), the number of apnoea and hypopnoea episodes per hour (apnoea-hypopnoea index), lowest nocturnal oxygen saturation and oxygen desaturation time were measured during overnight polysomnography before and after surgery. A successful tonsillectomy was defined as an apnoea-hypopnoea index improvement ratio of > or =50% and an apnoea-hypopnoea index <20 after operation.
  
  
  RESULTS
  Apnoea-hypopnoea index decreased from 69.0 +/- 28.4/h to 30.1 +/- 24.0/h (P < 0.0001). Simple tonsillectomy was successful in all six patients with body mass index <25 kg/m2. Concerning success rate of simple tonsillectomy with tonsil, size 2 was lowest (42.9%). Eight of the 13 patients who used continuous positive airway pressure before simple tonsillectomy did not use continuous positive airway pressure after simple tonsillectomy because of a significant reduction of excessive daytime sleepiness. Continuous positive airway pressure decreased significantly after simple tonsillectomy from 13.6 +/- 2.5 cmH2O preoperatively to 10.6 +/- 1.3 cmH2O postoperatively (P < 0.05).
  
  
  CONCLUSIONS
  These data suggest that simple tonsillectomy is a beneficial modality to treat OSAS in selected patients (larger tonsil, low body mass index), even in adults.
authors.affiliation: Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, Nagoya, Japan. seisay@med.nagoya-u.ac.jp
authors.forename: S
authors.initials: S
authors.lastname: Nakata
authors.forename: A
authors.initials: A
authors.lastname: Noda
authors.forename: E
authors.initials: E
authors.lastname: Yanagi
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
authors.forename: H
authors.initials: H
authors.lastname: Yamamoto
authors.forename: T
authors.initials: T
authors.lastname: Nakashima
mesh_terms: D000328:Adult; D015992:Body Mass Index; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014066:Palatine Tonsil / Q000033:anatomy & histology*; D017286:Polysomnography; D011446:Prospective Studies; D012307:Risk Factors; D020181:Sleep Apnea, Obstructive / Q000601:surgery*; D014068:Tonsillectomy / Q000379:methods*; D016896:Treatment Outcome