Management of Hyperglycemia in Acute Cerebral Stroke

Abstract

Stress hyperglycemia is defined as a transient plasma glucose level above 200 mg/dL and it is thought to be caused by the increased levels of cortisol,glucagon,and epinephrine. These hormones increase gluconeogenesis and decrease peripheral uptake of glucose to ensure substrate availability Causes of hyperglycemia in critical ill patients include diabetes mellitus stimulation of stress hormones (epinephrine, cortisol), glucocorticoid therapy, continuous enteral nutrition and decreased activity. In healthy individuals without DM, the regulation of blood glucose concentration is maintained throughhormonal, neural, and hepatic autoregulatory mechanisms Under normalcircumstances, a postprandial increase in blood glucoseconcentration stimulates the release of insulin from the pancreas, specifically the b-cells. Insulin mediates peripheral glucose disposal and suppresses glucogenesis in theliver, This process maintains blood glucose homeostasis. After uptake into the skeletal muscle, glucose either isdirected to glucagon formation (pathway for carbohydrate storage) or glycolysis (used in the Kreb’s cycle,esulting in energy production),excess glucose also canbe stored in the liver or converted to fatty acids for storage in adipose tissue. Hyperglycemia after acute stroke may be attributable to several underlying mechanisms. These include: a non-specific reaction to acute stress; autonomic, hormonal, and metabolic alterations as a result of tissue injury; uncovering of underlying latent diabetes by the acute stroke; activation of the hypothalamo-hypophyseal-adrenal axis attributable to a direct effect of brain ischemia on the pituitary; and irritation of the glucose regulatory centers in the brain by a stroke. Anyone experiencing symptoms of a stroke requires immediate medical help. Even if the ultimate diagnosis is not stroke, many diseases that can mimic a stroke are also medical emergencies,if a physician cannot be contacted by telephone,the person should be taken to the nearest hospital emergency department at once. Many types of stroke require immediate treatment, and most of the promising new therapies for stroke are effective only if started within a few hours of the onset of symptoms.