Table 5 The summary of the main findings of this review

• The proportion of people worldwide with Diabetes undergoing isolated CABG surgery has increased by 33% in recent years to 25–40%

• The incidence of diagnosed Diabetes continues to rise, and high levels of undiagnosed Diabetes and pre-diabetes are reported in surgical patients.

• Pre- and peri-operative hyperglycaemia is associated with worse outcomes following cardiac surgery

• Evidence suggests that pre-operative hyperglycaemia in patients without Diabetes carries greater clinical significance; than in patients already with diagnosed Diabetes.

• Cardiac surgical patients without Diabetes with pre-operative hyperglycaemia have a 1 year mortality double that of patients with normoglyacemia, and equivalent to patients already diagnosed with Diabetes.

• No uniform consensus in the UK or Europe exists, for glycaemic management of patients with Diabetes or pre-diabetes undergoing cardiac surgery.

• Patients with well controlled Diabetes may achieve comparable outcomes to patients without Diabetes with similar glycaemic control.

• This review supports the pre-operative screening, and optimisation of glycaemic control in patients undergoing cardiac surgery.

• The optimal glycaemic management of cardiac surgical patients remains unclear and requires definition

• Clear guidelines relating to the glycaemic management of cardiac surgical patients are needed in the UK and Europe