The acute effects of uvulopalatopharyngoplasty on breathing during sleep in sleep apnea patients.

Uvulopalatopharyngoplasty (UPPP) is frequently employed in the treatment of obstructive sleep apnea (OSA). Despite anecdotal reports of early post-UPPP deaths and the recommendation by some authors to perform a prophylactic tracheotomy for selected patients at the time of UPPP, there has been no systematic examination of breathing during sleep in the early post-UPPP period. In order to evaluate the early postoperative risk and the need for prophylactic tracheotomy in UPPP patients, we conducted polysomnograms (PSGs) on eight obese OSA patients on the second post-UPPP night and on another obese OSA patient on the fifth night after surgery. Postoperatively during wakefulness there was a significant increase in the alveolar-arterial oxygen gradient (p less than 0.05); in three individuals, the PaO2 was sufficiently reduced to warrant supplemental oxygen. For the group of nine patients there were no differences between the pre- and post-UPPP apnea index (AI), hypopnea index (HI), or apnea plus hypopnea index during non-rapid eye movement sleep. In individual patients, the pattern of sleep-disordered breathing events was variably altered, but there was a reciprocal relationship between the changes in AI and HI (r = 0.75; p less than 0.02). The duration of apnea in non-rapid eye movement sleep was shorter in four patients and unchanged in five patients postoperatively. Although the mean nadir of hemoglobin saturation was unchanged before and after UPPP, one patient desaturated to dramatically low levels in association with several excessively prolonged apneas post-UPPP. Desaturation was probably minimized in the three patients receiving supplemental oxygen. There were no serious adverse effects resulting directly from sleep-disordered breathing or nocturnal hemoglobin oxygen desaturation following UPPP. Our data suggest that performing a tracheotomy in a nonselective fashion in OSA patients undergoing UPPP is not warranted. In lieu of this, these individuals should be carefully monitored following surgery. In addition, patients with severe OSA and/or moderate-to-severe nocturnal hemoglobin oxygen desaturation should be considered for early postoperative PSGs as should those individuals who are more hypoxemic while awake following surgery. Patients who require supplemental oxygen postoperatively should also be studied to ensure adequate oxygenation and to monitor for acute, oxygen-related prolongation of apnea.