Table 2 Results of multivariate analyses of risk factors for NIV failure, ICU mortality, and hospital mortality

Risk factors for NIV failure

 Delirium

1.97 (1.34–2.88)

 < 0.01

2.33 (1.27–4.30)

 < 0.01

1.84 (1.13–2.99)

0.02

 APACHE II score

1.08 (1.03–1.12)

 < 0.01

1.09 (1.02–1.17)

0.02

1.10 (1.05–1.15)

 < 0.01

 GCS

0.78 (0.66–0.91)

 < 0.01

–

–

–

–

 RR, breaths/min

1.03 (1.00–1.05)

0.02

–

–

–

–

 PaCO₂, mmHg

0.975 (0.968–0.982)

 < 0.01

–

–

–

–

 PaO₂/FiO₂, mmHg

0.996 (0.993–0.998)

 < 0.01

–

–

0.995 (0.992–0.998)

 < 0.01

 Age, years

–

–

1.04 (1.01–1.08)

 < 0.01

–

–

 HR, beats/min

–

–

1.01 (1.00–1.03)

0.04

–

–

 Diabetes mellitus

–

–

–

–

0.57 (0.36–0.91)

0.02

Risk factors for ICU mortality

 Delirium

2.58 (1.74–3.84)

 < 0.01

3.64 (1.89–7.01)

 < 0.01

2.16 (1.31–3.56)

 < 0.01

 APACHE II score

1.06 (1.01–1.11)

0.01

1.18 (1.09–1.28)

 < 0.01

1.06 (1.01–1.11)

0.03

 GCS

0.77 (0.65–0.91)

 < 0.01

–

–

–

–

 RR, breaths/min

1.04 (1.01–1.06)

 < 0.01

–

–

1.03 (1.00–1.06)

0.03

 PaCO₂, mmHg

0.978 (0.970–0.985)

 < 0.01

–

–

–

–

 PaO₂/FiO₂

0.998 (0.995–1.000)

0.04

–

–

0.997 (0.994–1.000)

0.04

 Age, years

–

–

1.04 (1.01–1.08)

0.03

–

–

 Risk factors for hospital mortality

 Delirium

2.55 (1.74–3.75)

 < 0.01

3.34 (1.81–6.18)

 < 0.01

2.11 (1.29–3.45)

 < 0.01

 APACHE II score

1.08 (1.03–1.13)

 < 0.01

1.09 (1.02–1.17)

0.02

1.09 (1.04–1.14)

 < 0.01

 HR, beats/min

1.01 (1.00–1.02)

0.05

1.02 (1.00–1.03)

0.01

–

–

 RR, breaths/min

1.03 (1.00–1.05)

0.03

–

–

1.03 (1.00–1.06)

0.02

 GCS

0.82 (0.67–0.97)

0.02

–

–

–

–

 PaCO₂, mmHg

0.975 (0.968–0.983)

 < 0.01

–

–

–

–

 PaO₂/FiO₂

–

–

–

–

0.997 (0.995–1.000)

0.05

 Age, years

–

–

1.06 (1.03–1.10)

 < 0.01

–

–