Methods: Patients were randomised to off-pump coronary artery bypass grafting (OPCAB) or conventional coronary artery bypass grafting with cardiopulmonary bypass (CABG-CPB). Small intestine function was assessed by differential four sugars (0=methyl-D-glucose, D-xylose, L-rhamnose, and Lactulose) permeability and absorption tests before surgery, at day 1 and day 5 post-surgery. Liver function was assessed before and at the end of surgery by monoethylglycinexyhdide (MEGX)/Iidocaine ratios after injection of 1 mg/kg bolus of lidocaine and by serial measurements of transaminases (AST and ALT), bilirubin, and alkaline phosphatase (ALP).