The present study was a randomized control trial following CONsolidated Standards of Reporting Trials (CONSORT) guideline. After institutional review board (IRB) approval (November 19, 2019), the trial was conducted in DM patients who were set for cardiac surgery undergoing cardiopulmonary bypass (CPB) at the Cardiac Center, King Chulalongkorn Memorial Hospital. Inclusion criteria were 20–80 years of age, DM Type 2 (T2DM), and scheduling for elective valvular heart surgery (VHS) or coronary artery bypass graft (CABG). Exclusion criteria were 1) DM Type 1, 2) insulin-dependent T2DM, 3) BG <60 or >300 mg/dL from 6 pm of the day before surgery, 4) preoperative administration of insulin, glucose, or dextrose solution, 5) preoperative inotropes/vasopressors infusion or mechanical cardiovascular support devices, 6) history of postoperative nausea or vomiting (PONV), 7) thyroid cancer or endocrine neoplasia syndromes, 8) chronic pancreatitis or previous surgery of pancreas, 9) recent steroid administration, 10) pregnancy, and 11) current treatment with GLP-1 analogs. Written informed consent was obtained from all the enrolled samples.