Electronic database search – Medline, the Cochrane Library, Embase, Ovid, the NHS Scotland e-Library, SIGN, NICE and Google

51 potentially relevant abstracts identified

9 studies excluded: No extractable data for cardiac surgery patients

42 studies identified with extractable data for cardiac surgery patients

13 studies excluded: No reference to tight vs normal glucose control

29 studies identified comparing tight vs normal glucose control

20 studies excluded: Non RCTs No efforts to blind/randomise Unclear method Target glucose levels for tight or control group not specified No original data

9 RCTs met inclusion criteria

3 studies excluded: No comparable outcome measures

6 RCTs included in meta-analysis