Postoperative evaluation of sleep apnea after uvulopalatopharyngoplasty

Uvulopalatopharyngoplasty (UPPP) is an operation that is frequently performed for the treatment of obstructive sleep apnea (OSA). While UPPP usually eliminates or decreases snoring and often reduces excessive daytime sleepiness, the decrease in the number of episodes of apnea and hypopnea, and the improvement in oxygen saturation (SaO2) have been less predictable. We compared preoperative and postoperative polysomnography (PSG) in 27 patients with OSA and found that no single PSG parameter could accurately reflect the changes in respiration seen after UPPP. We suggest that a combination of indices including the apnea index, the apnea and hypopnea index, the frequency and severity of decreases in SaO2, and the lowest SaO2 be used to assess the effect of UPPP. Using this combination we determined that 30% of our patients were markedly improved, 33% were somewhat improved, and 37% were unimproved. To rely solely on the patient's subjective improvement often results in overestimating the therapeutic results of surgery, whereas to rely only on one PSG parameter may underestimate or overestimate the degree of improvement.