Outcome from NIV and relationship with arterial blood gas variables: univariate analysis
| NIV success (n = 72) | NIV failure (n = 16) | OR (95% CI) | p Value | |
| Baseline pH, n = 88* | 7.26 (0.06) | 7.22 (0.08) | 3.96 (1.55 to 5.07) | 0.02 |
| Baseline PaO2 (kPa), n = 88* | 8.15 (2.73) | 8.30 (2.31) | 0.98 (0.80 to 1.20) | 0.87 (NS) |
| Baseline PaCO2 (kPa), n = 88* | 10.20 (2.19) | 10.20 (2.16) | 0.99 (0.78 to 1.28) | 0.99 (NS) |
| Baseline calculated bicarbonate (mmol/l), n = 88* | 26.09 (3.44) | 23.51 (3.69) | 1.24 (1.04 to 1.45) | 0.014 |
| 1 h pH, n = 88* | 7.29 (0.06) | 7.25 (0.09) | 1.78 (0.04 to 2.23) | 0.03 |
| 1 h PaCO2 (kPa), n = 88* | 8.84 (2.21) | 9.50 (2.61) | 0.88 (0.68 to 1.15) | 0.36 (NS) |
| 1 h PaO2 (kPa), n = 88* | 8.77 (2.87) | 7.85 (1.64) | 1.27 (0.84 to 1.91) | 0.26 (NS) |
| 4 h pH, n = 84* | 7.32 (0.51) | 7.28 (0.90) | 4.34 (2.90 to 5.89) | 0.14 (NS) |
| 4 h PaO2 (kPa), n = 84* | 8.37 (2.39) | 7.70 (1.22) | 1.27 (0.79 to 1.96) | 0.31 (NS) |
| 4 h PaCO2 (kPa), n = 84 * | 8.19 (1.98) | 8.47 (2.07) | 0.93 (0.68 to 1.27) | 0.66 (NS) |
Values are given as mean (SD).
*t test.
NIV, non-invasive ventilation; NS, non-significant.