Low-Flow Anesthesia and Perioperative Atelectasis in Laparoscopic Bariatric Surgery

The goal of this clinical trial is to learn whether low-flow anesthesia reduces perioperative atelectasis compared to normal-flow anesthesia in adults undergoing laparoscopic bariatric surgery. The main questions it aims to answer are: Does low-flow anesthesia result in a smaller increase in lung ultrasound score from baseline to postoperative hour 1? Does low-flow anesthesia result in better preservation of pulmonary function at postoperative hour 48? Researchers will compare low-flow anesthesia (fresh gas flow 0.5 L/min) to normal-flow anesthesia (fresh gas flow 2 L/min) to see if low-flow anesthesia reduces the extent of perioperative atelectasis as measured by lung ultrasound. Participants will: Be randomly assigned to receive either low-flow or normal-flow inhalational anesthesia with sevoflurane during surgery Undergo lung ultrasound assessments before surgery and at postoperative hours 1 and 24 Undergo spirometric testing one day before surgery and at postoperative hour 48

NCT Number	NCT07041567
Lead Sponsor	Istanbul University
Conditions	Atelectasis, Pulmonary Complications, Ultrasonography, Bariatric Surgery, Low Flow Anesthesia
Enrollment	60 participants
Start Date	2026-01-15
Primary Completion	2026-04-01 (estimated)
Study Completion	2026-04-15 (estimated)
Updated on ClinicalTrials.gov	2026-05-20