To ensure patient safety, the target blood glucose concentration must be closely monitored and the results known to the clinical staff treating the patients. As patient safety is paramount, it is not possible to blind the clinical staff to treatment allocation. In this open-label trial, bias will be minimised by ensuring concealment of treatment allocation prior to randomisation. The unblinded design risks introducing a systematic difference in some other treatment between the two groups, this is unlikely in the ICU setting where many other interventions will be administered simultaneously. The primary outcome measure is mortality and therefore not subject to ascertainment bias.