Impact of Lung Function Prehabilitation to Postoperative Pulmonary Complications

Inclusion Criteria: * adults 18 years or older * scheduled for the upper abdominal surgery under general anesthesia with intraoperative mechanical ventilation * possess adequate cognitive function to comprehend and follow instructions * possess sufficient physical capacity to perform structured prehabilitation exercises * express willingness to participate in the intervention program before surgery Exclusion Criteria: * pregnancy * pre-existing severe pulmonary diseases such as chronic obstructive pulmonary disease (COPD) * planned laparoscopic procedures * history of significant neuromuscular impairment (e.g: stroke) * declined to participate