RESUMEN
OBJECTIVE: Prolonged partial obstruction (PPO) is a common finding in sleep studies. Although not verified, it seems to emerge in deep sleep. We study the effect of PPO on sleep architecture or sleep electroencephalography (EEG) frequency. METHODS: Fifteen OSA patients, 15 PPOâ¯+â¯OSA patients and 15 healthy subjects underwent a polysomnography. PPO was detected from Emfit mattress signal. Visual sleep parameters and median NREM sleep frequency of the EEG channels were evaluated. RESULTS: The amount of deep sleep (N3) did not differ between the PPOâ¯+â¯OSA and control groups (medians 11.8% and 13.8%). PPOâ¯+â¯OSA-patients' N3 consisted mostly of PPO. PPOâ¯+â¯OSA patients had lighter sleep than healthy controls in three brain areas (Fp2-A1, C4-A1, O1-A2, p-valuesâ¯<â¯0.05). CONCLUSION: PPO evolved in NREM sleep and especially in N3 indicating that upper airway obstruction does not always ameliorate in deep sleep but changes the type. Even if PPOâ¯+â¯OSA-patients had N3, their NREM sleep was lighter in three EEG locations. This might reflect impaired recovery function of sleep.