Table 1 baseline characteristics of the patients

Age (years)

57 ± 15

Gender (female/male)

4/10

Pneumonia

13/14

History of COPD (GOLD II-IV)^a

7/14

ARDS^a

8/14

SAPS II at admission

35 ± 10

LTOT before

4/14

Home NIV before

2/14

Active smoking

11/14

Mortality

3/14

Days on mechanical ventilation

36 ± 26

Days in ICU

41 ± 37

 pH day 1

7.24 ± 0.1

 PaCO₂ day 1 (mmHg)

72 ± 20

 PaO₂ day 1 (mmHg)

82 ± 19

 P/F ratio day 1 (mmHg)

124 ± 41

 PEEP day 1 (cmH₂O)

14 ± 2

 P_insp day 1 (cmH₂O)

30 ± 4

 Tidal volume day 1 (ml)

470 ± 88

 PEEP day 7 (cmH₂O)

13 ± 2

 P_insp day 7 (cmH₂O)

26 ± 4

 Tidal volume day 7 (ml)

450 ± 101