Baseline and postintervention capillary blood gas results
| Target SpO2 range | NHF manual | NHF automatic | ||||
| 88%–92% N=5 | 92%–96% N=5 | All N=10 | 88%–92% N=6 | 92%–96% N=4 | All N=10 | |
| Baseline | Mean (SD) | |||||
| pH | 7.44 (0.02) | 7.47 (0.06) | 7.5 (0) | 7.46 (0.06) | 7.47 (0.02) | 7.5 (0) |
| PCO2 (mm Hg) | 35.9 (6.2) | 30.5 (4.9) | 33.2 (6) | 40.0 (7.0) | 32.6 (5.2) | 37 (7.1) |
| PO2 (mm Hg) | 59.0 (4.7) | 68.9 (9.3) | 63.9 (8.7) | 62.6 (12.9) | 68.9 (6.9) | 65.1 (10.9) |
| Target SpO2 range | 88%–92% N=5 | 92%–96% N=5 | All N=10 | 88%–92% N=6 | 92%–96%* N=3 | All* N=9 |
| Postintervention | Mean (SD) | |||||
| pH | 7.46 (0.02) | 7.47 (0.05) | 7.5 (0) | 7.47 (0.04) | 7.47 (0.02) | 7.5 (0) |
| PCO2 (mm Hg) | 35.9 (6.1) | 30.7 (6.2) | 33.3 (6.4) | 40.4 (6.5) | 34.0 (4.7) | 38.2 (6.5) |
| PO2 (mm Hg) | 56.6 (5.6) | 73.4 (12.6) | 65 (12.8) | 56.1 (6.0) | 74.2 (8.7) | 62.1 (11.1) |
*One participant in the automatic titration 92%–96% group was withdrawn and subsequently required mechanical ventilation, hence an end of intervention blood gas was not taken.
NHF, nasal high-flow; PCO2, partial pressure of carbon dioxide; PO2, partial pressure of oxygen.