SELESTIAL: Trial of Insulin to Control Blood Sugar After Acute Stroke Using Magnetic Resonance Imaging (MRI) End-Points

High blood sugar (hyperglycaemia) affects 40% of acute stroke patients and has a major adverse effect on survival and recovery. Increased production of lactic acid in brain tissue that has a poor blood supply is postulated to be the mechanism by which high blood sugar may worsen brain injury after stroke. Treatment with insulin infusions is proposed as a neuroprotective strategy, and a clinical trial is ongoing to test this hypothesis. However, the biological basis for insulin treatment has not been established, and there is uncertainty about the duration of insulin infusion that may be required to limit damage. Magnetic resonance spectroscopy (MRS) is a brain scanning technique that allows measurement of brain lactic acid. When performed in conjunction with conventional MRI scanning, the relationship of lactate accumulation to stroke expansion can be established. SELESTIAL is a randomised, placebo-controlled trial of insulin infusions of 24 or 72 hours (h) duration in acute stroke patients with hyperglycaemia, to establish whether insulin prevents lactate accumulation over the initial 72h after stroke, how this relates to stroke evolution, and the effect of treatment on stroke size and clinical outcomes at 1 week.