High-flow nasal cannula oxygen during endotracheal intubation in hypoxemic patients: a randomized controlled clinical trial.

Purpose: Intubation of hypoxemic patients is associated with life-threatening adverse events. High-flow therapy by nasal cannula (HFNC) for preoxygenation before intubation has never been assessed by randomized study. Our objective was to evaluate the efficiency of HFNC for preoxygenation, compared to high fraction-inspired oxygen facial mask (HFFM).
Methods: Multicenter, randomized, open-labelled, controlled PREOXYFLOW trial (NCT 01747109) in six French intensive care units. Acute hypoxemic adults requiring intubation were randomly allocated to HFNC or HFFM. Patients were eligible if PaO2/FiO2 ratio was below 300 mmHg, respiratory rate at least 30/min and if they required FiO2 50% or more to obtain at least 90% oxygen saturation. HFNC was maintained throughout the procedure, whereas HFFM was removed at the end of general anaesthesia induction. Primary outcome was the lowest saturation throughout intubation procedure. Secondary outcomes included adverse events related to intubation, duration of mechanical ventilation and death.
Results: A total of 124 patients were randomized. In the intent-to-treat analysis, including 119 patients (HFNC n = 62; HFFM n = 57), the median (interquartile range) lowest saturation was 91.5% (80-96) for HFNC and 89.5% (81-95) for the HFFM group (p = 0.44). There was no difference for difficult intubation (p = 0.18), intubation difficulty scale, ventilation-free days (p = 0.09), intubation-related adverse events including desaturation <80% or mortality (p = 0.46).
Conclusions: Compared to HFFM, HFNC as a preoxygenation device did not reduce the lowest level of desaturation.