 Several studies have shown that hyperglycemia is associated with poor outcomes in hospitalized patients. Postoperative glucose levels are a significant predictor of infection rates after cardiac surgery and death rate. Based on these observational studies, a randomized controlled intervention trial in surgical ICU patients demonstrated that intensive insulin therapy reduced the overall in-hospital mortality by 34 and stream infection by 46 . Using continuous glycemic monitoring CGM it has been shown that intensive insulin therapy based on discontinuous glucose monitoring revealed that normoglycemia is achieved only 22 of time. The researchers aim is to determine if real time CGM with a new generation mini invasive device, Glucoday S, would allow quickly adjusting insulin infusions rates according to interstitial glucose levels and decreasing both hyperglycemic and hypoglycemic excursions. This study will further investigate whether application of real time CGM to titrate insulin therapy to target glycemia in a tight range 80-110 mgdl can improve diabetic patient outcome after coronary artery bypass grafting CABG. 