Effects of Esketamine-Dexmedetomidine Combination on Immediate Postprocedural Oxygenation Index in Severe Pneumonia Patients Undergoing Bedside Fiberoptic Bronchoscopic Sputum Aspiration: A Prospective Randomised Controlled Trial.

Purpose: The aim was to investigate the effect of esketamine-dexmedetomidine (ESK-DEX) combination on immediate postprocedural oxygenation index (OI) in severe pneumonia patients undergoing bedside fiberoptic bronchoscopic (FOB) sputum aspiration, and provide clinical reference. Methods: A total of 90 patients diagnosed with severe pneumonia receiving non-invasive mechanical ventilation (NIV) who underwent bedside FOB were randomly and evenly divided into three groups: Group C (local anesthesia alone), Group D (DEX alone), Group ED (ESK-DEX). The primary outcome was the OI immediately after procedure (T1). The secondary outcomes: the OI was calculated at 6 h (T2), 12 h (T3), and 24 h (T4) after procedure; the mean arterial pressure (MAP) and heart rate (HR) were assessed at the following time points: FOB tip passage through nostril (t1), glottis (t2), 5 minutes after procedure (t3), and upon procedure completion (t4); Additionally, perioperative adverse events were also documented. Results: The Group ED demonstrated significantly higher OI compared to Group C at T1 (mean difference, -8.1; 95% CI, -13.48, -2.64; P=0.001). Similarly, the Group ED demonstrated significantly higher OI compared to Group C at each time point from T2 to T4, respectively (all P<0.05). Regarding hemodynamic parameters, both Group ED and Group D exhibited significantly lower MAP and HR values compared to Group C from t1 to t4 time points, respectively (all P<0.05). The total incidence of adverse events in Group ED was significantly reduced compared to Groups C (P=0.033). Conclusion: Compared with conventional sedation protocols, the ESK-DEX combined regimen demonstrated superior OI preservation immediately after procedure, enhanced OI within 24 hours postoperatively, improved hemodynamic stability, and enhanced safety profile in severe pneumonia patients undergoing bedside FOB-guided suction therapy. This pharmacodynamic synergy addresses critical gaps in FOB sedation-simultaneously preventing hypoxemia, maintaining respiratory drive, and minimizing adverse events.