Upper abdominal surgeries under general anaesthesia causes decrease in PEFR (Peak expiratory flow rate) values as lung compliance will be reduced because of general anaesthesia and upper abdominal surgery will limit the lung movements because of pain. Objective of this study is to find the effect of general anaesthesia in patients undergone upper abdominal surgery in Saveetha Medical College and hospital, Tamilnadu. METHODOLOGY:After research ethics board approval, 45 patients scheduled for upper abdominal surgeries under general anaesthesia are measured for PEFR values preoperative and postoperatively using wright peak flow meter. RESULT:In the 45 patients studied, PEFR values are reduced for all postoperatively. CONCLUSION:Patients who has undergone upper abdominal surgeries under general anaesthesia will have reduced PEFR values because general anaesthesia will decrease respiratory muscle tone, decreased lung volume accompanied by reduced lung compliance and upper abdominal surgery will limit the lung movements because of pain.

Keywords : Upper Abdominal Surgery, General Anaesthesia, Peak Expiratory Flow Rate, Lung Compliance.