Table 2.
Changes in daytime arterial blood gasses, lung function, hours of non-invasive ventilation and transcutaneous carbon dioxide and oxygen saturation after the start of non-invasive ventilation
| ALS group | Non-ALS group | Between groups | |||||
|---|---|---|---|---|---|---|---|
| Baseline, N = 30 | Change 0–2 months (N = 12) | Change 0–6 months (N = 19) | Baseline (N = 47) | Change 0–2 months (N = 17) | Change 0–6 months (N = 43) | P value for difference in change 0–6 months | |
| PaCO2 (kPa) | 6.6 ± 0.8 | −1.2 ± 0.4* | −0.7 ± 0.3* | 6.6 ± 1.0 | −1.1 ± 0.2* | −0.7 ± 0.2* | 0.862 |
| PaO2 (kPa) | 10.4 ± 0.9 | 1.8 ± 0.7* | 0.3 ± 0.4 | 9.6 ± 1.6 | 0.3 ± 0.7* | 1.3 ± 0.3* | 0.035¶ |
| FVC (% pred) | 41.6 ± 13.7 | – | −9.8 ± 3.7* | 45.2 ± 16.6 | – | 2.5 ± 2.1 | 0.005¶ |
| FEV1 % FVC | 88.1 ± 13.8 | – | −3.2 ± 3.4 | 76.2 ± 12.3 | – | 3.0 ± 2.9 | 0.247 |
| NIV initiated, N = 28 | N = 27 | N = 23 | NIV initiated, N = 46 | N = 43 | N = 42 | ||
|---|---|---|---|---|---|---|---|
| Hours NIV | 7.7 ± 3.8 | 3.5 ± 1.3* | 3.8 ± 1.5* | 6.8 ± 1.7 | 0.9 ± 0.4* | 1.1 ± 0.4* | 0.031 |
| tcpCO2 (kPa) | 6.5 ± 0.9 | −1.6 ± 0.3* | −2.5 ± 0.4 | 6.4 ± 0.9 | −1.5 ± 0.2* | −1.7 ± 0.3* | 0.111 |
| tcSpO2 (%) | 95.9 ± 1.5 | 3.3 ± 0.4 | 3.8 ± 0.5* | 95.1 ± 1.7 | 6.1 ± 1.0* | 6.0 ± 1.1* | 0.103 |
Baseline data are presented as mean ± standard deviation
Changes over time are presented as mean ± standard error of mean
kPa kilo Pascal, PaCO 2 partial pressure of arterial carbon dioxide, PaO 2 partial pressure of arterial oxygen, FVC forced vital capacity, FEV 1 forced expiratory volume in one second, %pred % predicted, NIV non-invasive ventilation, tcpCO 2 transcutaneous carbon dioxide, tcSpO 2 transcutaneous oxygen saturation
¶ p < 0.05: for difference in change between groups 0–6 months
* p < 0.05 for chances within groups from baseline