Table 1 Comparison of patients treated with high-flow nasal oxygen alone and those treated with non-invasive ventilation (NIV) for post-extubation respiratory failure

Characteristics of the patients at admission

Age, years

71 ± 9

70 ± 9

0.59

Male sex, n (%)

40 (65%)

53 (63%)

0.86

Body-mass index, kg/m²

29 ± 7

28 ± 7

0.91

SAPS II at admission, points

60 ± 18

56 ± 17

0.22

Underlying chronic cardiac disease, n (%)

27 (44%)

38 (45%)

0.84

Underlying chronic lung disease, n (%)

23 (37%)

34 (40%)

0.68

Chronic obstructive pulmonary disease, n (%)

18 (29%)

25 (30%)

0.92

Acute respiratory failure as reason for intubation, n (%)

35 (56%)

54 (64%)

0.34

Characteristics of the patients the day of extubation

SOFA score, points

4.5 ± 2.7

4.4 ± 2.8

0.84

Duration of mechanical ventilation, median (IQR), days

5 [3–11]

6 [4–10]

0.71

Weaning difficulty^a, n (%)

0.20

-Simple weaning

36 (58%)

49 (58%)

-Difficult or prolonged weaning

26 (42%)

35 (42%)

Ineffective cough, n/n total (%)

15/58 (26%)

31/82 (38%)

0,14

Abundant secretions, n/n total (%)

30/57 (53%)

32/83 (39%)

0,10

Administration of steroids before extubation, n (%)

4 (6%)

13 (15%)

0,09

Prophylactic NIV after extubation, n (%)

7 (11%)

56 (67%)

 < 0.001

Characteristics at time of respiratory failure

Interval between extubation and respiratory failure, hours

20 [5–47]

22 [4–57]

0.89

Systolic arterial pressure, mm Hg

136 ± 21

135 ± 26

0.82

Diastolic arterial pressure, mm Hg

67 ± 13

66 ± 16

0.68

Heart rate, beats/min

90 ± 28

87 ± 35

0.58

Respiratory rate, breaths/min

27 [23–33]

30 [25–37]

0.07

Clinical signs suggesting respiratory distress, n (%)

20 (32%)

33 (39%)

0.38

SpO₂, %

94 ± 7

95 ± 4

0.40

PaO₂, mm Hg

83 ± 39

80 ± 24

0.66

PaO₂/FiO₂, mm Hg

181 ± 72

187 ± 76

0.70

pH, units

7.46 ± 0.06

7.41 ± 0.10

 < 0.01

PaCO₂, mm Hg

41 ± 9

48 ± 17

 < 0.01

Hypercapnia (PaCO₂ > 45 mm Hg), n/n total (%)

13/50 (26%)

33/73 (45%)

0.03

Treatment duration between the onset of respiratory failure and recovery or reintubation, hours

Duration of high-flow nasal oxygen, hours

14 [2–54]

10 [1–33]

0.04

Duration of NIV, hours

0 [0–0]

12 [4–27]

 < 0.001