[Polysomnographic diagnosis of obstructive sleep apnea syndrome]

All night polysomnographic studies performed in 149 patients with OSA syndrome revealed marked disturbances of the sleep structure and the disorders of breathing during sleep: obstructive apneas in all patients, hypopneas in 25% and central apneas in 12%. The mean apnea index was 68 +/- 29, the mean percent of sleep time spent in apnea 50 +/- 21%. The typical obstructive apnea duration was 25 +/- 7s in NON REM sleep and 40 +/- 34s in REM sleep. The longest obstructive apnea duration was 48 +/- 24s in NON REM sleep and 71 +/- 42s in REM sleep. During obstructive apneas the typical arterial oxygen saturation was 82 +/- 9% in NON REM sleep and 71 +/- 17% in REM sleep; the lowest arterial oxygen saturation was 73 +/- 14% in NON REM sleep and 62 +/- 21% in REM sleep. Forty six percent of patients had apnea-related cardiac arrhythmias or conduction disturbances.