|
Supine
|
Head-up tilt
|
|---|
|
TPLN
|
VLFLN
|
LFLN
|
HFLN
|
LFNU
|
HFNU
|
LF:HF
|
TPLN
|
VLFLN
|
LFLN
|
HFLN
|
LFNU
|
HFNU
|
LF:HF
|
|---|
|
Room air
|
|
8.21
|
7.23
|
6.88
|
6.66
|
52.36
|
44.01
|
2.49
|
8.37
|
7.21
|
7.14
|
6.02†
|
66.58
|
24.05†
|
4.09
|
|
(0.68)
|
(0.89)
|
(0.64)
|
(1.11)
|
(21.93)
|
(21.57)
|
(3.94)
|
(1.05)
|
(0.83)
|
(1.01)
|
(1.25)
|
(19.49)
|
(13.90)
|
(3.05)
|
|
5%CO2
|
|
8.93
|
6.91
|
7.24
|
8.17*
|
22.97*
|
69.23*
|
0.38*
|
8.27
|
7.09
|
6.79
|
6.79*†
|
40.45*†
|
47.64*†
|
1.31*†
|
|
(0.88)
|
(0.54)
|
(1.10)
|
(1.17)
|
(11.54)
|
(15.37)
|
(0.26)
|
(1.08)
|
(0.94)
|
(1.26)
|
(1.55)
|
(21.41)
|
(21.11)
|
(1.43)
|
- Reported values are mean (SD) following transformation with natural logarithm function (LN), or normalised (NU) for total power (TP) of the spectrum between 0 and 0.5 Hz
- Very low frequency (VLF): 0–0.04 Hz, low frequency (LF): 0.04–0.15 Hz, high frequency (HF): 0.15–0.4 Hz
- * P < 0.03 between room air and 5%CO2
- †P < 0.03 between supine and head-up tilt
