METHODS: This is a pragmatic randomized control trial study where elective admitted patients will be randomly divided into the intervention (SS) or control (NN) group. All data will be collected during a face-to-face interview, anthropometric measurement, blood sampling (albumin, white blood count, hemoglobin, and c-reactive protein), handgrip strength, and postoperative complications. Group SS will be receiving a tailored lifestyle and intensively supplemented with oral nutrition support as compared to Group NN that will receive standard medical care. The primary outcome for this study is the length of stay in the hospital. Additional outcome measures are changes in biochemical profile and nutritional and functional status. The effects of intervention between groups on the outcome parameters will be analyzed by using the SPSS General Linear Model (GLM) for the repeated measure procedure.

DISCUSSION: The intervention implemented in this study will serve as baseline data in providing appropriate nutritional management in patients undergoing gastrointestinal and oncological surgery.