Skip to main content
. Author manuscript; available in PMC: 2014 Aug 22.
Published in final edited form as: Lancet. 2013 Aug 2;383(9918):736–747. doi: 10.1016/S0140-6736(13)60734-5

Figure 2. An example summary report from an overnight split night polysomnography.

Figure 2

Total time in bed was 489·5 min. Half of the night was diagnostic, half therapeutic. The hypnogram shows sleep stages throughout the night. Shortly before midnight, continuous positive airway pressure was started (Pmask increases from 0), which was followed by elimination of respiratory events, normalisation of arterial oxygen saturation, and REM rebound (>2 h of REM). Sleep efficiency is the proportion of time in bed spent asleep after lights out. Sleep latency is the time from lights out until the first epoch of sleep. REM latency is the time from lights out until the first epoch of sleep. An epoch is a time window of 30 s. CnA=central apnoea. ObA=obstructive apnoea. MxA=mixed apnoea. Hyp=hypnoea. Uns=unclear events. RERA=respiratory event related arousal. PLM=periodic limb movement. TST=total sleep time. REM=rapid eye movement. W=awake. NREM=non-rapid eye movement. R=right. B=back. L=left. F=front. U=upright. On the hypnogram, 1, 2, and 3 represent NREM stages 1, 2, and 3.