Fig. 2From: Incidence of oxygen desaturation using a high-flow nasal cannula versus a facemask during flexible bronchoscopy in patients at risk of hypoxemia: a randomised controlled trialThe high-flow nasal cannula and endoscopic facemask. a and b: high-flow nasal cannula device; c and d: endoscopic facemask used in flexible bronchoscopy. Bronchoscopy was performed through the nasal route in a supine positionBack to article page