Table 2.
Changes in respiratory parameters during high-flow oxygen via tracheostomy in Case 2
| HFT day | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| HFT setting | ||||||||||||
| FIO2 | 0.3 | 0.25 | 0.25 | 0.25 | 0.3 | 0.3 | 0.3 | 0.3 | 0.3 | 0.3 | 0.3 | 0.3 |
| Flow (L/minute) | 40 | 40 | 40 | 40 | 40 | 50 | 40 | 40 | 40 | 40 | 30 | 20 |
| RR (breaths/minute) | 39 | 22 | 26 | 24 | 24 | 31 | 32 | 30 | 30 | 23 | 26 | 20 |
| SpO2 (%) | 96 | 94 | 95 | 94 | 95 | 96 | 97 | 97 | 98 | 98 | 99 | 100 |
| etCO2 (mmHg) | 44 | 37 | 40 | 42 | 46 | 48 | 46 | 49 | 48 | 45 | 43 | 46 |
| VT (mL) | 220 | 210 | 210 | 230 | 220 | 220 | 230 | 230 | 230 | |||
| Arterial blood gases | ||||||||||||
| pH | 7.47 | 7.43 | 7.41 | 7.37 | 7.40 | 7.38 | 7.39 | 7.42 | 7.42 | 7.42 | 7.42 | |
| PaCO2 (mmHg) | 50 | 53 | 58 | 68 | 66 | 70 | 66 | 61 | 59 | 59 | 60 | |
| PaO2 (mmHg) | 61 | 73 | 68 | 77 | 80 | 86 | 79 | 91 | 93 | 72 | 85 | |
| HCO3− (mmol/L) | 53.1 | 34.7 | 35.9 | 38.5 | 40.1 | 40.1 | 38.8 | 39.1 | 37.9 | 36.9 | 37.8 | |
Abbreviations: etCO2 end-tidal carbon dioxide, FIO2 fraction of inspiratory oxygen, HFT high-flow oxygen via tracheostomy, HCO3− bicarbonate ion, PaCO2 partial pressure of arterial carbon dioxide, PaO2 partial pressure of arterial oxygen, RR respiratory rate, SpO2 arterial oxygen saturation by pulse oximetry, VT tidal volume (measured by Wright respirometer)