Glycemic control targets in intensive care units (ICUs) have three distinct domains. Firstly, excessive hyperglycemia needs to be avoided. The upper limit of this varies depending on the patient population studied and diabetic status of the patients. Surgical patients particularly cardiac surgery patients tend to benefit from a lower upper limit of glycemic control, which is not evident in medically ill patient. Patient with premorbid diabetic status tends to tolerate higher blood sugar level better than normoglycemics. Secondly, hypoglycemia is clearly detrimental in all groups of critically ill patient and all measures to avoid this catastrophe need to be a part of any glycemic control protocol. Thirdly, glycemic variability has increasingly been shown to be detrimental in this patient population. Glycemic control protocols need to take this into consideration and target to reduce any of the available metrics of glycemic variability. Newer technologies including continuous glucose monitoring techniques will help in titrating all these three domains within a desirable range.
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