A randomised controlled trial comparing high‐flow nasal oxygen with standard management for conscious sedation during bronchoscopy

, satisfaction scores and complications. Thirty participants were allocated to each group. Baseline patient characteristics, procedure time and anaesthetic agents used were similar between the groups. Desaturation occurred in 4 out of 30 patients allocated to the high-flow nasal oxygen group, compared with 10 out of 30 allocated to the standard oxygenation group, a non-significant difference (p = 0.07) with intention to treat analysis. The difference was significant (p = 0.047) when using a per-protocol analysis. Oxygen saturation after pre-oxygenation and the lowest oxygen saturation during procedure were significantly higher in the high-flow nasal oxygen group compared with the standard oxygenation group; median (IQR range 100 (99-100 93-100) vs. 98 (97-99 94-100), p = 0.0001 and 97.5 (94-99 77-100) vs. 92 (88-95 79-98), p < 0.001, respectively. There were no differences in other secondary outcomes. Although high-flow nasal oxygen may prevent desaturation due to some causes, it does not protect against hypoxaemia in all circumstances.