Table 1.
Basic demographic characteristics of stable COPD patients.
| Total (n = 19) | Group 1 (n = 10) HFNC then NC |
Group 2 (n = 9) NC then HFNC |
p value | |
|---|---|---|---|---|
| Age (year) | 70.4 ± 8.7 | 74.3 ± 5.6 | 66.0 ± 9.6 | 0.04* |
| Male sex | 18 (94.7) | 10 (100%) | 8 (88.9) | 0.28 |
| Height (cm) | 162.5 ± 6.6 | 162.3 ± 6.2 | 162.8 ± 7.3 | 0.88 |
| Body weight (kg) | 60.7 ± 9.9 | 63.7 ± 7.5 | 57.4 ± 11.6 | 0.18 |
| BMI (kg/m2) | 22.9 ± 3.1 | 24.3 ± 2.3 | 21.3 ± 3.3 | 0.03* |
| Smoking history (pack per day*years) | 55.3 ± 33.6 | 61.0 ± 31.8 | 48.9 ± 36.2 | 0.45 |
| Symptoms | ||||
| Wheeze | 1 (5.3) | 0 (0) | 1 (11.1) | 0.28 |
| Cough | 14 (73.7) | 7 (70.0) | 7 (77.8) | 0.70 |
| Sputum | 16 (84.2) | 9 (90.0) | 7 (77.8) | 0.47 |
| Dyspnea | 6 (31.6) | 2 (20.0) | 4 (44.4) | 0.25 |
| Medication | ||||
| LAMA + LABA | 8 (42.1) | 3 (30.0) | 5 (55.6) | 0.45 |
| LAMA + LABA + ICS | 4 (21.1) | 2 (20.0) | 2 (22.2) | |
| ICS + LABA | 2 (10.5) | 2 (20.0) | 0 (0) | |
| LAMA | 5 (26.3) | 3 (30.0) | 2 (22.2) | |
| Pulmonary rehabilitation | 4 (21.1) | 2 (20.0) | 2 (22.2) | 0.91 |
| Comorbidity | ||||
| Coronary artery disease | 3 (15.8) | 1 (10.0) | 2 (22.2) | 0.47 |
| Chronic heart failure | 1 (5.3) | 1 (10.0) | 0 (0) | 0.33 |
| Old stroke | 0 (0) | 0 (0) | 0 (0) | N/A |
| COPD severity | ||||
| GOLD 1 (FEV1 ≥ 80% predicted) | 1 (5.3) | 1 (10.0) | 0 (0) | 0.71 |
| GOLD 2 (50% ≤ FEV1 ≤ 79% predicted) | 6 (31.6) | 3 (30.0) | 3 (33.3) | |
| GOLD 3 (30% ≤ FEV1 ≤ 49% predicted) | 9 (47.4) | 5 (50.0) | 4 (44.4) | |
| GOLD 4 (FEV1 < 30% predicted) | 3 (15.8) | 1 (10.0) | 2 (22.2) | |
| Spirometry | ||||
| FEV1/FVC (%) | 45.8 ± 10.2 | 49.5 ± 11.4 | 41.7 ± 7.3 | 0.10 |
| FEV1 (L) | 1.00 ± 0.4 | 1.1 ± 0.4 | 0.9 ± 0.3 | 0.48 |
| FEV1 (% predicted) | 45.5 ± 15.6 | 49.8 ± 17.4 | 40.8 ± 12.6 | 0.22 |
| FVC (L) | 2.2 ± 0.7 | 2.2 ± 0.6 | 2.3 ± 0.8 | 0.76 |
| FVC (% predicted) | 72.6 ± 18.5 | 74.3 ± 18.9 | 70.8 ± 18.9 | 0.69 |
| FEV3 (L) | 1.6 ± 0.5 | 1.6 ± 0.5 | 1.5 ± 0.5 | 0.74 |
| FEV3 (% predicted) | 53.0 ± 13.7 | 56.0 ± 13.9 | 49.6 ± 13.4 | 0.32 |
| FEF 25–75% (L/s) | 0.4 ± 0.2 | 0.5 ± 0.3 | 0.3 ± 0.1 | 0.22 |
| FEF 25–75% (% predicted) | 26.6 ± 19.9 | 34.4 ± 24.2 | 17.9 ± 8.5 | 0.70 |
| PEF (L/s) | 2.6 ± 1.0 | 2.9 ± 1.0 | 2.3 ± 0.9 | 0.21 |
| PEF (% predicted) | 43.8 ± 17.6 | 51.3 ± 18.3 | 35.6 ± 13.1 | 0.05* |
| Body plethysmography | ||||
| RV (L) | 3.7 ± 2.1 | 3.8 ± 2.8 | 3.6 ± 1.0 | 0.86 |
| RV (% predicted) | 172.8 ± 93.6 | 169.6 ± 122.3 | 176.3 ± 53.3 | 0.88 |
| TLC (L) | 6.1 ± 2.1 | 6.1 ± 2.6 | 6.0 ± 1.3 | 0.94 |
| TLC (% predicted) | 106.6 ± 33.9 | 109.5 ± 44.9 | 103.3 ± 16.9 | 0.70 |
| RV/TLC (%) | 59.3 ± 11.4 | 58.3 ± 13.6 | 60.4 ± 9.0 | 0.69 |
| FRC (L) | 4.6 ± 2.0 | 4.8 ± 2.7 | 4.4 ± 1.0 | 0.71 |
| FRC (% predicted) | 151.2 ± 64.5 | 154.9 ± 86.3 | 147.0 ± 30.9 | 0.80 |
| IC (L) | 1.5 ± 0.4 | 1.3 ± 0.3 | 1.6 ± 0.5 | 0.15 |
| IC (% predicted) | 57.1 ± 22.4 | 58.4 ± 28.8 | 55.7 ± 13.8 | 0.80 |
| Small airway disease (FEF 25–75% < 65% predicted) | 18 (94.7) | 9 (90.0) | 9 (100.0) | 0.33 |
Continuous data are expressed as mean ± SD with t test.
Categorical data are expressed as number (%) with Chi-square test.
COPD chronic obstructive pulmonary disease, HFNC high flow nasal cannula, NC nasal cannula, BMI body mass index, LAMA long-acting muscarinic antagonists, LABA long-acting β2 sympathomimetic agonists, ICS inhaled corticosteroid, N/A not applicable, GOLD global initiative for chronic obstructive lung disease, FEV1 forced expiratory volume that has been exhaled at the end of the first second of forced expiration, FVC forced vital capacity, FEV3 forced expiratory volume that has been exhaled at the end of the third second of forced expiration, FEF 25–75% forced expiratory flow at 25–75% of the pulmonary volume, PEF peak expiratory flow, RV residual volume, TLC total lung capacity, FRC functional residual capacity, IC inspiratory capacity.
*Significance between group 1 and group 2.