Comparison of baseline and treatment for low-intensity NPPV (n=13) and high-intensity NPPV (n=15)
| Baseline | After 6 weeks of NPPV | Difference (95% CI) | p Value | |
| LI-NPPV-Paco2 01.00 h (mm Hg)* | 61.5±5.8 | 58.0±9.4 | −3.6 (−9.1 to 2.0) | 0.19 |
| HI-NPPV-Paco2 01.00 h (mm Hg)* | 63.6±7.7 | 49.6±7.8 | −14.0 (−18.5 to −9.4) | <0.001 |
| LI-NPPV-Paco2 12.00 h (mm Hg)† | 56.4±5.8 | 52.7±7.9 | −3.6 (−8.9 to 1.6) | 0.16 |
| HI-NPPV-Paco2 12.00 h (mm Hg)† | 58.0±7.6 | 51.8±6.4 | −6.2 (−9.5 to −2.9) | <0.001 |
| LI-NPPV-HCO3− 01.00 h (mmol/l)* | 33.4±2.8 | 31.5±2.4 | −1.9 (−4.5 to 0.5) | 0.11 |
| HI-NPPV-HCO3− 01.00 h (mmol/l)* | 34.3±3.6 | 30.2±3.2 | −4.1 (−5.8 to −2.4) | <0.001 |
| LI-NPPV-HCO3− 12.00 h (mmol/l)† | 32.6±2.7 | 30.5±2.3 | −2.2 (−4.5 to 0.2) | 0.07 |
| HI-NPPV-HCO3− 12.00 h (mmol/l)† | 33.8±4.9 | 30.4±3.6 | −3.4 (−4.9 to −1.9) | <0.001 |
| LI-NPPV-FEV1 (l) | 0.76±0.29 | 0.80±0.37 | 0.04 (−0.07 to 0.16) | 0.44 |
| HI-NPPV-FEV1 (l) | 0.74±0.29 | 0.85±0.39 | 0.11 (0.01 to 0.21) | 0.037 |
| LI-NPPV-VC (l) | 1.95±0.45 | 2.07±0.68 | 0.13 (−0.17 to 0.42) | 0.37 |
| HI-NPPV-VC (l) | 1.96±0.58 | 2.14±0.62 | 0.22 (0.06 to 0.39) | 0.012 |
| LI-NPPV-BDS after 6MWT‡ | 9 (4/10) | 6 (4/10) | 0.55 | |
| HI-NPPV-BDS after 6MWT‡ | 9 (4/10) | 4 (3/5) | 0.014 | |
| LI-NPPV-6MWD | 252±131 | 291±111 | 38.5 (−2.7 to 79.7) | 0.065 |
| HI-NPPV-6MWD | 264±129 | 297±125 | 32.9 (−24.3 to 90.1) | 0.24 |
| LI-NPPV-PImax (kPa) | 4.8±1.6 | 5.1±1.5 | 0.37 (−0.59 to 1.33) | 0.41 |
| HI-NPPV-PImax (kPa) | 5.0±2.3 | 5.6±2.5 | 0.53 (−0.2 to 1.3) | 0.16 |
| LI-NPPV-SRI-SS | 58.0±14.6 | 63.2±18.9 | 5.3 (−0.42 to 11.0) | 0.066 |
| HI-NPPV-SRI-SS | 55.8±15.5 | 62.2±16.3 | 6.4 (1.5 to 11.2) | 0.014 |
Data are presented as mean±SD unless otherwise stated.
6MWT, 6-minute walking test; BDS, Borg dyspnoea scale; FEV1, forced expiratory volume in 1 s; HI-NPPV, high-intensity non-invasive positive pressure ventilation; HCO3−, bicarbonate; LI-NPPV, low-intensity non-invasive positive pressure ventilation; Paco2, arterial carbon dioxide tension; PImax, maximal inspiratory mouth occlusion pressure; SRI-SS, Severe Respiratory Insufficiency Questionnaire Summary Score; TLC, total lung capacity; VC, vital capacity.
↵* Blood gases taken during night time non-invasive ventilation.
↵† Blood gases taken under spontaneous breathing.
↵‡ Median values with IQR.