In severe OSAS,the mean duration of respiratory events in REM period is prolonged,so the RDI is decreased with no significant difference of the impairment to the respiratory and SaO 2 between the REM and NREM period.

• 重度组患REM期较NREM期RDI减少 ,但呼吸及血氧损害程度无显著变化 ,显然是REM期呼吸紊乱的平均持续时间延长所致