Table 1 Demographics and clinical characteristics of patients before HFNC start (n = 150)

Age—year

74 [60–80]

Male sex—no. (%)

81 (54%)

SOFA Score

4 [2–4]

APACHE II Score

11 [8–13]

Charlson’s Comorbidity Index

5 [3–6]

Comorbidities—no. (%)*

 COPD

52 (35%)

 Cystic fibrosis

9 (6%)

 Others respiratory

22 (15%)

 Hypertension

47 (31%)

 Malignancies

38 (25%)

  Haematological

24 (15%)

  Respiratory

7 (5%)

  Others

7 (5%)

 Cardiac

25 (17%)

 Congestive heart failure

20 (13%)

 Diabetes mellitus

17 (11%)

 Neurologic

15 (10%)

 Renal

10 (7%)

 Hepatic

6 (4%)

Immunocompromised—no. (%)^§

48 (32%)

Reason for hospital admission—no. (%)

 Respiratory

99 (66%)

 Surgery

10 (7%)

 Extrapulmonary sepsis

10 (7%)

 Cardiac

6 (4%)

 Mixed cardiac—respiratory

2 (1%)

 Others

23 (15%)

Cause of acute respiratory failure—no. (%)

 Community-acquired pneumonia

71 (48%)

 Hospital-acquired pneumonia

27 (18%)

 COPD

15 (10%)

 Others respiratory

17 (11%)

 Cardiac failure

12 (8%)

 Mixed cardiac—respiratory

8 (5%)

Bilateral infiltrates on chest radiograph—no. (%)

65 (43%)