Effects of uvulopalatopharyngoplasty on collapsibility of the retropalatal airway in patients with obstructive sleep apnea.

OBJECTIVES/HYPOTHESIS: Uvulopalatopharyngoplasty improves sleep-disordered breathing, particularly in patients with sleep-disordered breathing with abnormally high collapsible airway exclusively at the retropalatal airway, as was previously reported. The present study examined the direct and long-term effects of uvulopalatopharyngoplasty on retropalatal airway collapsibility.

STUDY DESIGN

Prospective longitudinal study of 18 patients with abnormally high collapsible airway exclusively at the retropalatal airway.

METHODS

Closing pressure of the retropalatal airway was estimated by endoscopically obtaining static pressure/area relationship of the passive pharynx in completely paralyzed and anesthetized patients with sleep-disordered breathing (n = 18) before and 3 months after uvulopalatopharyngoplasty. The measurements were repeated 1 year after uvulopalatopharyngoplasty in eight of these patients.

RESULTS

Uvulopalatopharyngoplasty decreased retropalatal airway closing pressure by 3.5 cm H2O; furthermore, a direct correlation between the severity of sleep-disordered breathing (as determined by nocturnal oximetry) and retropalatal airway closing pressure was revealed. Uvulopalatopharyngoplasty failures revealed retropalatal airway closing pressure greater than atmospheric pressure. Reduced retropalatal airway collapsibility was maintained up to 1 year after uvulopalatopharyngoplasty. Two patients developed marked stenosis of the retropalatal airway with aggravation of sleep-disordered breathing after initial improvement of sleep-disordered breathing and retropalatal airway collapsibility.

CONCLUSIONS

Uvulopalatopharyngoplasty decreases the retropalatal airway collapsibility. The effect is maintained for at least 1 year after uvulopalatopharyngoplasty, whereas a few patients develop retropalatal airway stenosis leading to recurrence of sleep-disordered breathing.