Alterations of the serum cortisol and blood glucose in brain-injured patients.

Serial serum cortisol and blood glucose measurements in brain- injuried patients showed consistently higher levels in comatose patients than in patients with other injuries not involving the brain or brain stem. In the brain-injured patients the cortisol and glucose levels were related to the degree of injury, with higher and more widely scattered values found with deeper levels of unconsciousness. The cortisol and glucose levels showed 4 distinct patterns of response, depending upon the level of coma. The observed hyperglycaemia was directly related to cortisol levels up to 12 mmol/l glucose whereas higher blood glucose levels appeared to be related to the concentrations of other hormones, e.g. glucagon, growth hormone and the catecholamines. In brain-injured patients persistently high levels of glucose and cortisol in blood portend a fatal outcome.