Background and objective: High flow nasal oxygen (HFNO) has been shown to reduce desaturations during flexible bronchoscopy. We evaluated
outcomes of HFNO vs. low flow nasal oxygen (LFNO) on intraprocedural hypoxemia, the demand of sedative and reversal medications, postprocedure
complications, procedure conversion to general anaesthesia and patient comfort during outpatient standard and EBUS (Endo Bronchial
Ultrasound) guided bronchoscopy under conscious sedation.
Methods: A Prospective open-label study where the first 42 patients were allocated to LFNO and subsequent 42 patients were allocated to HFNO.
Baseline and lowest oxygen saturation, duration of hypoxemia, procedure type, amount of sedative and reversal medications and patient comfort
Results: Both HFNO and LFNO had similar characteristics at baseline. The odds ratio of being hypoxic (<90%) was 13.8 times more in the LFNO
group (CI 3.55-70.7, p < 0.001) after adjustment for confounders. In addition, the LFNO group had a longer period of desaturation (OR 11.24, CI
3.18-49.78, p < 0.001). There was no statistically significant difference in median lowest peripheral oxygen saturation, the amount of sedative and
reversal medications, patient comfort, procedure conversion to general anaesthesia, and post-procedure complications between the two groups.
Conclusion: During outpatient standard and EBUS guided bronchoscopy, HFNO is associated with a statistically significant reduction in oxygen
desaturation and duration of hypoxemia. However, there was no clinically significant difference in adverse outcomes, or patient comfort between
the two groups. We would like to highlight that LFNO can be considered safe to be used during outpatient bronchoscopy under conscious sedation
which is cost effective. However, further multicentre studies are needed to identify high risk patients who will benefit most from HFNO.