Effects of Insulin and Glycaemic Management on Neuromuscular Function

Observational studies have indicated an association between stress-induced hyperglycaemia and neuromuscular complications in critically ill patients. This observation is further supported by electrophysiological findings from two randomized controlled trials which suggested that titrating insulin therapy to achieve a normal blood glucose has a beneficial effect on neuromuscular function, associated with a reduced need for prolonged mechanical ventilation. The underlying pathophysiological mechanisms explaining these clinical observations are not well understood. There is no clear evidence that insulin has anabolic effects on muscle nor that it provides mitochondrial protection. It is possible that the effect of insulin therapy reflects a protective action on peripheral nerves; however, this hypothesis awaits confirmation. Overall, the potential benefits on neuromuscular function must be considered in light of large-scale randomized trials which demonstrate equivalent or worse outcome in critically ill patients managed with intensive insulin therapy.