High-Flow Nasal Oxygenation During Sedation for Transcatheter Aortic Valve Replacement: The HIGH-OXY-TAVR Randomised–Controlled Trial

<b>Background:</b> Data on high flow nasal oxygenation (HFNO) efficacy in hypoxia prevention in transcatheter aortic valve replacement (TAVR) are conflictive. We aimed to determine the benefit of HFNO in preventing the occurrence of desaturations during TAVR. <b>Methods:</b> An investigator-initiated, proof of concept, single-centre, randomised, and controlled trial on 132 adult patients who were scheduled to undergo transfemoral TAVR was conducted. Patients were randomised (1:1) to HFNO (H-group) with a flow rate of 50 L min^-1 and FiO₂ 0.6 or standard of care oxygen therapy (S-group). The primary endpoint was the number of patients with a desaturation episode (SpO₂ < 93%) for >10 s during TAVR. Secondary outcomes included arterial partial pressure of oxygen (pO₂) 45 min from sedation start and changes in glomerular filtration rate from baseline to 12 h post-procedure. <b>Results:</b> Between 23 November and 24 July, a per-protocol analysis was performed in a total of 125 patients (H-group <i>n</i> = 64; S- group <i>n</i> = 61; 49 females). The number of patients with any desaturation episode was significantly lower in the H-group [13/64 (20%, 95% CI: 12-32%)] than in the S-group [31/61 (51%, 95% CI: 39-63%), RR: 0.39 (95%CI: 0.23-0.68)]. At 45 min, mean (SD) pO₂ was higher in the H-group (24(9.8) kPa vs. 16.7(7.5) kPa; <i>p</i> < 0.005). A significant improvement in delta median (IQR) difference on glomerular filtration rate was observed in the H-group [1.6(-1-7.9) mL min^-1 1.73 m^-2] with respect to the S-group [0.2(-6.1-3.1) mL min^-1 1.73 m^-2; <i>p</i>-value: 0.013]. <b>Conclusions:</b> This trial demonstrated that HFNO provides a better oxygenation pattern than standard oxygen therapy during TAVR. Larger studies focusing on long-term clinical outcomes are warranted to evaluate the benefit of HFNO during sedation for TAVR procedures.