High-flow nasal cannula oxygen therapy in post-anesthesia care unit (PACU) reduces postextubation atelectasis in patients undergoing esophageal cancer surgery: A randomized controlled trial

Background Esophageal cancer surgery frequently leads to post-extubation atelectasis. The efficacy of high-flow nasal cannula (HFNC) oxygen therapy in the post-anesthesia care unit (PACU) for these patients remains unvalidated. Methods This randomized controlled trial enrolled 100 patients after esophageal cancer surgery, allocated to a control group (conventional oxygen therapy at 5 L/min, n = 50) or an HFNC group (heated and humidified oxygen at 40% FiO₂, 37°C, 10 L/min, n = 50). The primary outcome was the lung ultrasound score at pre-extubation (T1), 30 minutes post-intervention (T2), and before PACU discharge (T3). The secondary outcome measures included PaO 2 /FiO 2 , hypoxemia, incidence of pulmonary complications within 7 days post-intervention. Results The reduction in lung ultrasound score from T1 to T3 was significantly greater in the HFNC group (mean change: −5.6 points) than in the control group (mean change: −1.4 points), with a between-group difference of −4.2 points (95% CI: −4.7 to −3.7; P < 0.001). At T2 and T3, lung ultrasound score were significantly lower in the HFNC group (T2: 8.7 ± 1.2 vs. 12.7 ± 1.5; T3: 7.6 ± 1.0 vs. 11.7 ± 1.1; both P < 0.001). The HFNC group also had significantly higher PaO₂/FiO₂ ratios at T2 (325 ± 38 vs. 295 ± 35 mmHg) and T3 (340 ± 32 vs. 305 ± 30 mmHg) (both P < 0.001), and a lower incidence of hypoxic events (12.0% vs. 28.0%, P = 0.046) and 7-day postoperative pulmonary complications (10.0% vs. 36.0%, P = 0.002). No significant differences were found in sedation scores or hemodynamic parameters. Conclusion The utilization of HFNC oxygen therapy in the PACU may provide a safe and effective means of mitigating the severity of atelectasis subsequent to extubation, enhancing oxygenation levels, and decreasing the incidence of early pulmonary complications in patients who have undergone surgical interventions for esophageal cancer.