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Carbohydrate drink: The administration of a complex carbohydrate-rich drink before surgery (100gm the evening before surgery and 50gm 2-3 hours preop) may increase insulin sensitivity but does not reduce complications or significantly improve other outcomes when compared to placebo fluids (1).
Larger trials are required to establish impact on protein catabolism and on clinical outcomes. In addition, drinks containing simple carbohydrates may not have the same impact on insulin response and further research is required in comparison to placebo fluids and complex carbohydrate containing drinks. Further research is also required prior to use of carbohydrate drinks in diabetics or other patients at risk for hyperglycemia.
For more information, see Chapter 4: Preoperative Fasting and Carbohydrate Treatment in The SAGES / ERAS® Society Manual of Enhanced Recovery Programs for Gastrointestinal Surgery
References
1. Smith MD, McCall J, Plank L, Herbison GP, Soop M, Nygren J. Preoperative carbohydrate treatment for enhancing recovery after elective surgery. Cochrane Database Syst Rev 2014 Aug 14; 8: CD009161
