Although insulin treatment for critically ill patients has become a standard of care, efficacy might well vary with different ICUs. A study published in 2001 reported that intensive insulin therapy with blood glucose maintained at or below 6 mmol/l reduced morbidity and mortality in critically ill patients in surgical ICUs [32]. However, subsequent studies on intensive insulin therapy of critically ill patients in medical ICUs showed that this treatment could reduce morbidity but not mortality [33]. The debate over this issue remains, and a study published in 2009 found that intensive glycaemic control could increase mortality in adults in ICUs, but increasing target glucose levels to 10 mmol/l could reduce mortality [34]. A recent review separately examined surgical and medical patients and suggested that, to treat hyperglycaemia, insulin therapy should be used to maintain the glucose level between 8 mmol/l and 10 mmol/l. This treatment could reduce the mortality and morbidity resulting from high FBG and lower the occasional risk of hypoglycaemia associated with intensive insulin therapy [35].