Clinical variables at baseline and at 3-month follow-up
| AVAPS | Fixed-level PS | |||||
| Baseline | Follow-up | p Value | Baseline | Follow-up | p Value | |
| Age (years) | 53±9 | 56±11 | ||||
| Gender (male/female) | 12/13 | 11/14 | ||||
| Emergency/elective presentation | 9/16 | 9/16 | ||||
| BMI (kg/m2) | 50±8 | 48±9 | 0.007 | 52±8 | 51±7 | 0.024 |
| Fat-free mass (kg) | 69±17 | 68±18 | 0.493 | 72±18 | 71±18 | 0.870 |
| Waist circumference (cm) | 141±18 | 136±17 | 0.006 | 145±14 | 146±14 | 0.120 |
| Neck circumference (cm) | 46±6 | 46±7 | 0.340 | 48±5 | 48±7 | 0.084 |
| FEV1 (% predicted) | 53±15 | 59±14 | 0.039 | 55±15 | 60±16 | 0.222 |
| FVC (% predicted) | 52±14 | 58±13 | 0.019 | 56±15 | 62±18 | 0.189 |
| PaCO2 (kPa) | 7.0±0.7 | 6.4±0.8 | 0.004 | 6.8±0.8 | 6.2±0.8 | 0.021 |
| PaO2 (kPa) | 8.9±1.2 | 9.1±1.2 | 0.660 | 8.7±1.8 | 9.3±1.2 | 0.163 |
| HCO3 (mmol/litre) | 31±3 | 29±3 | 0.001 | 31±4 | 27±3 | 0.003 |
The p values refer to paired t test analysis from initiation to follow-up values within each group.
AVAPS, average-volume-assured pressure support; BMI, body mass index; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; HCO3, arterial concentration of bicarbonate; PaCO2, arterial partial pressure of carbon dioxide; PaO2, arterial partial pressure of oxygen; PS, pressure support.