Aim: To review the most significant studies on the pathophysiology of hypoglycaemia and hyperglycaemia in neurocritical patients and the therapeutic interventions used to control them.
Development: Available evidence shows that hypoglycaemia and hyperglycaemia increase brain injury and aggravate the prognosis, but it fails to establish the most suitable levels of blood glucose. Intensive treatment with insulin, compared with more moderate regimes, has not improved the prognosis and leads to further episodes of hypoglycaemia.
Conclusions: Hypoglycaemia must always be avoided. Intensive treatment to control hyperglycaemia does not offer any kind of advantages and increases the likelihood of hypoglycaemia; it therefore cannot be recommended in neurocritical patients. No evidence is available showing the optimal level of blood glucose or the most suitable insulin regime, although its use is generally indicated when blood glucose levels are higher than 180-200 mg/dL. The value of the pharmacological control of blood glucose levels to improve the prognosis remains uncertain.