The study looks at how different levels of oxygen affect lung issues after lung surgery. *Pulmonary reexpansion* means getting the lung back to normal after it has been collapsed during surgery. *FiO2* stands for Fraction of Inspired Oxygen, which is the amount of oxygen you breathe in. This research compares two oxygen levels: 80% and 30%, to see which helps patients recover better after surgery. *Postoperative pulmonary complications (PPCs)* are lung problems that can happen after surgery, and they are quite common. The study will help doctors decide the best oxygen levels to use during lung surgeries to reduce these complications. Participants need to have planned thoracic surgery, be between 18 and 80 years old, and meet certain health conditions. The study will take place over 7 days after surgery. Participants will help improve patient care in future surgeries.

• The study lasts for 7 days after surgery.
• Participants must undergo thoracic surgery and meet health criteria.
• The study will help improve oxygen use in surgeries.