Comparison of high-flow nasal cannula oxygen therapy versus nasal cannula in sedated transoesophageal echocardiography in patients with mitral regurgitation: a prospective, randomized controlled clinical trial.

BACKGROUND: Patients with moderate-to-severe mitral regurgitation (MR) undergoing pre-procedural transesophageal echocardiography (TEE) for transcatheter edge-to-edge repair (TEER) are at high risk for hypoxia during propofol sedation. We evaluated the efficacy and safety of high-flow nasal cannula (HFNC) oxygen therapy compared with conventional nasal cannula in this population. METHODS: This prospective, single-center, randomized controlled trial enrolled 263 patients with moderate-to-severe MR scheduled for pre-procedural TEE under propofol sedation. Patients were randomized to receive either HFNC or conventional nasal cannula. The primary outcome was the incidence of hypoxia. Secondary outcomes included subclinical respiratory depression, need for airway interventions, hemodynamic parameters, adverse events, and satisfaction scores. RESULTS: HFNC significantly reduced hypoxia incidence compared with conventional oxygen (13.74% vs. 23.48%; relative risk 0.59, 95% CI 0.35–0.99; p = 0.040). HFNC also decreased subclinical respiratory depression (18.32% vs. 32.58%; p = 0.007) and need for jaw-lift maneuvers (20.61% vs. 33.33%; p = 0.026). No patients in the HFNC group required mask ventilation versus 12.88% in the control group (p < 0.001). Operator and anesthesiologist satisfaction scores were higher with HFNC (both p < 0.01). No serious HFNC-related adverse events occurred. CONCLUSIONS: HFNC significantly reduces hypoxia and airway interventions during pre-procedural TEE in patients with MR, with improved safety and satisfaction profiles.