Table 1 Baseline population characteristics

Demographics

Age, years

60 ± 16

59 ± 17

63 ± 15

Male sex

89 (52%)

54 (61%)

35 (40%)

Arrest characteristics

Out-of-hospital arrest

96 (56%)

58 (61%)

38 (51%)

Initial rhythm VT/VF

64 (38%)

31 (33%)

33 (44%)

Therapeutic hypothermia used

113 (66%)

76 (80%)

37 (49%)

Pittsburgh cardiac arrest category

 1

28 (16%)

9 (9%)

19 (25%)

 2

63 (37%)

26 (27%)

37 (49%)

 3

32 (19%)

19 (20%)

13 (17%)

 4

47 (28%)

41 (43%)

6 (8%)

First PaO₂:FiO₂ ratio

241 ± 137

249 ± 129

231 ± 146

Dynamic compliance, mL/cm H₂O

29 ± 12

29 ± 12

28 ± 13

Initial SOFA-respiratory score

 0

26 (15%)

13 (14%)

13 (17%)

 1

33 (19%)

24 (25%)

9 (12%)

 2

33 (19%)

17 (18%)

16 (21%)

 3

46 (27%)

26 (27%)

20 (27%)

 4

32 (19%)

15 (16%)

17 (23%)

Initial SOFA-cardiovascular score

 0

76 (45%)

33 (35%)

43 (57%)

 1

18 (11%)

8 (8%)

10 (13%)

 2

10 (6%)

9 (9%)

1 (1%)

 3

31 (18%)

22 (23%)

9 (12%)

 4

25 (21%)

23 (24%)

12 (16%)

Cumulative vasopressor index

1.4 ± 1.9

1.7 ± 1.9

1.1 ± 1.9

Time to first FiO₂ wean, h

6.3 ± 6.4

6.8 ± 6.9

5.8 ± 5.6

Number of FiO₂ changes in 24 h

2.5 ± 1.5

2.5 ± 1.6

2.6 ± 1.4