Continuous pressure measurements in the pharynx and esophagus during sleep in patients with obstructive sleep apnea syndrome.

Pressure measurements were made preoperatively at six sites in the pharynx and esophagus in 18 obstructive sleep apnea syndrome (OSAS) patients, 3 social snorers, and 6 healthy normal controls. Repeat measurements were made approximately 2 months after uvulopalatopharyngoglossoplasty (UPPGP) in 10 of the OSAS patients. The pressure transducers were contained in a thin silicone tube inserted through one nostril, and measurements were made both in the awake state and throughout a night's sleep. Oxygen saturation was also continuously recorded and, additionally, nasal and oral airflow measurements were made as the postoperative control. The majority of patients had obstruction in more than one pharyngeal segment, and the site(s) of obstruction differed in the awake and sleeping states. After UPPGP, 3 of the patients had neither subjective nor objective evidence of obstruction, while the remaining 7, although subjectively improved, had varying degrees of residual obstruction in the nasopharynx and at the level of the soft palate.