Table-I.

Main indices before and after treatment (x̄±s).

	PaO2 (mmHg)		PaCO2 (mmHg)		a/AO2		OI
	Observation	Control	Observation	Control	Observation	Control	Observation	Control
Before	44.83±5.26	45.38±5.8	59.35±6.96	58.12±7.69	0.19±0.13	0.18±0.12	13.7±2.8	14.0±3.1
12 h after	80.75±11.73	75.69±10.85	49.32±6.35	49.96±7.20	0.68±0.17	0.37±0.17	6.9±1.9	9.8±3.0
T	13.13	11.26	5.23	18.31	11.03	4.89	9.25	5.10
P	<0.01	<0.01	<0.01	<0.01	<0.01	<0.01	<0.01	<0.01