Effects of Periodic Recruitment Maneuvers on Atelectasis and Respiratory Mechanics During Elective Spine Surgery Assessed by Lung Ultrasonography

During general anesthesia, especially when patients are placed in the prone (face-down) position for spine surgery, parts of the lungs may partially collapse. This condition, called atelectasis, can reduce oxygen levels and affect breathing during and after surgery. Although anesthesiologists routinely use a breathing technique known as an alveolar recruitment maneuver to reopen collapsed lung areas, performing this maneuver only once at the beginning of surgery may not be sufficient to keep the lungs open throughout longer procedures. The purpose of this study is to determine whether performing alveolar recruitment maneuvers at regular intervals during surgery can better prevent lung collapse compared with performing a single maneuver at the start of surgery. The study will include adult patients undergoing elective lumbar spine surgery under general anesthesia in the prone position. All participants will receive standard anesthesia care and a baseline alveolar recruitment maneuver after being positioned for surgery. Participants will then be randomly assigned to one of two groups. One group will receive additional alveolar recruitment maneuvers approximately once every hour during surgery, while the other group will not receive further recruitment maneuvers beyond the initial one. Lung aeration will be assessed using lung ultrasound, a non-invasive imaging method that does not involve radiation. The main outcome of the study is the presence of significant lung collapse immediately before removal of the breathing tube at the end of surgery. Secondary outcomes include measurements of breathing mechanics, oxygen levels, and the occurrence of temporary drops in oxygen saturation. The results of this study may help determine the most effective way to maintain lung function during prone spine surgery and improve respiratory safety during anesthesia.