Song IK, Jang YE, Lee JH, et al. - Researchers undertook this randomized controlled, patient- and sonographer-blinded trial to investigate how different F_IO₂ (fraction of inspired oxygen) can influence the development of intraoperative atelectasis in mechanically ventilated children using lung ultrasound. Assignment of 86 children (≤ 6 years) undergoing noncardiac surgery to a low (n = 43) or high (n = 43) F_IO₂ group was done. Consistently, 30% air-oxygen mixture during preoxygenation, ultrasound-guided recruitment maneuver, and mechanical ventilation were provided to the low F_IO₂ group. In the high F_IO₂ group, 100% oxygen during preoxygenation and ultrasound-guided recruitment maneuver and 60% air-oxygen mixture during mechanical ventilation were received. Both groups had a positive end-expiratory pressure of 5 cm H₂O applied. One minute following the commencement of mechanical ventilation and at the termination of surgery, lung ultrasound was performed in both groups. Findings revealed no influence of F_IO₂ on significant atelectasis formation in mechanically ventilated children who received ultrasound-guided recruitment maneuver and positive end-expiratory pressure.