Table 3.

Sleep time, respiratory rate (RR) and arterial O₂ saturation (S_pO₂) measured by pulse oximetry

Parameter	Wake (n = 38)	REM (n = 36)	N1 (n = 35)	N2 (n = 38)	N3 (n = 34)
Sleep time (min)	85.5 ± 63.3	65.9 ± 31.5	15.3 ± 11.4* , §	215.6 ± 66.3* , §	64.8 ± 52.8
RR (bpm)	16.8 ± 2.4	15.2 ± 3.0*	15.7 ± 2.8†	15.5 ± 2.2*	15.9 ± 2.4†
SpO2 (%)	97.1 ± 1.2	97.0 ± 1.2‡	96.7 ± 1.5‡	96.6 ± 1.5†	96.2 ± 1.2* , ¶

REM, rapid‐eye‐movement. *P < .0001 versus Wake. †P < .01 versus Wake. ‡P < .05 versus Wake. §P < .0001 versus REM. ¶P < .01 versus REM.