Effect of visual lung recruitment manoeuvres guided by trans-oesophageal lung ultrasound on atelectasis after thoracoscopic lobectomy: a randomised, single-blind, prospective study.

Background: Although the incidence of postoperative atelectasis could be reduced using lung recruitment manoeuvres, it remains high. We hypothesised that intraoperative visual lung recruitment guided by trans-oesophageal lung ultrasound would be more effective than the conventional method for managing postoperative atelectasis.

Methods: In this randomised, controlled, prospective study, 84 patients undergoing thoracoscopic lobectomy were recruited from Affiliated Chengdu Fifth People^'s Hospital (teaching hospital) in China. Patients were grouped into trans-oesophageal lung ultrasound-guided (Group G, n = 42) and control (Group C, n = 42) groups.

Methods: Lung recruitment was performed after anaesthesia induction, before chest closure and before the endotracheal tube extubation. In Group C, recruitment pressure was controlled at 30 cm H₂O for 10 s (performed thrice); in Group G, the pressure was controlled at 30 cm H₂O (performed thrice), and the tidal volume did not exceed 20 ml kg^-1 until no atelectasis was detected by trans-oesophageal ultrasound. The primary outcome was lung ultrasound scores measured at the post anaesthesia care unit 30 min after extubation. The secondary outcomes included the oxygenation index (30 min after extubation) and the incidence of atelectasis (30 min after extubation and 3 days after surgery).

Results: The final analysis included 79 patients. The lung ultrasound score was significantly higher in the control group than in the ultrasound-guided group 30 min after extubation (Group C vs. Group G, 8.6 ± 2.6 vs. 6.5 ± 2.0, P < 0.001). No significant difference in the oxygenation indexes 30 min after extubation was observed between the groups (P = 0.074); however, the incidence of atelectasis 30 min after extubation significantly differed between the two groups (Group C vs. Group G, 57% vs. 33%, P = 0.031). The incidence of atelectasis 3 days after surgery did not significantly differ between the two groups (Group C vs. Group G, 45% vs. 28%, P = 0.122).

Conclusions: Lung recruitment guided by trans-oesophageal lung ultrasound can reduce lung ultrasound scores and the incidence of atelectasis at the post anaesthesia care unit 30 min after extubation. However, it does not significantly reduce the incidence of atelectasis 3 days after surgery. TRIAL REGISTRATION: Registration number: ChiCTR2200062509. Registered on 10 /8/ 2022.