. 2008 Apr 21;12(2):R55. doi: 10.1186/cc6875

Table 3.

Temperature and humidity of the medical gas with and without the heated humidifier in patients with acute respiratory failure

	Temperature (°C)	Absolute humidity (mgH₂O/l)	Relative humidity (%)
CPAP_VENTwith HH	32.4 ± 1.4^a,c	34.1 ± 2.8^a,b,c	98.1 ± 1.8^a,c
CPAP_VENTwithout HH	29.5 ± 2.0^a	18.4 ± 5.5^a,b	61.4 ± 14.7^a,b
CPAP_LFwith HH	32.3 ± 1.0^a,c	33.9 ± 1.9^a,c	98.0 ± 1.0^a,c
CPAP_LFwithout HH	28.5 ± 1.7^a	11.4 ± 4.8^a	40.4 ± 15.5^c
CPAP_HFwith HH	29.4 ± 1.1^c	24.2 ± 5.4^c	82.3 ± 18.3^c
CPAP_HFwithout HH	27.4 ± 1.2	6.4 ± 1.8	24.6 ± 6.9

^aP < 0.05 versus CPAP_HF; ^bP < 0.05 versus CPAP_LF; ^cP < 0.05 versus each mode of CPAP without HH. CPAP, continuous positive airway pressure; CPAP_VENT, ventilator CPAP; CPAP_LF, continuous low-flow CPAP; CPAP_HF, continuous high-flow CPAP; HH, heated humidifier.