Extremely high blood glucose levels (hyperglycemia) may lead to a coma Nonketotic hyperglycemic-hyperosmolar coma This type of coma occurs in Type 11diabetics. More than 50% of persons who go into this type of coma die. It occurs when there is hyperglycemia with inadequate fluid intake and resulting (dehydration). This condition can occur along with an acute infection.

Causes of this condition are infections such as acute pneumonia untreated Type 11 diabetes, and initiation of corticosteroid or diuretic treatment. The blood glucose level is usually >55mmol/l. This condition can cause circulatory collapse and death.

DIABETIC KETOACIDOSIS

Another type of diabetic coma can occur. Diabetic ketoacidosis occurs in Type 1 diabetics. This happens when there is an acute shortage of insulin availability (usually caused by a lapse in treatment, or severe infection).
There is a resultant hyperglycemia with osmotic diuresis causing severe dehydration and can lead to coma and death if not adequately identified and rapidly treated. Signs of developing ketoacidosis are polyuria, nausea, vomiting, occasionally abdominal pain, lethargy and sleepiness.

ACUTE HYPOGLYCEMIA

This occurs when there is too little glucose in the blood for normal body functioning to occur. If the blood glucose levels drop below 3.5-4mmol/l (50mg/dl) the body starts reacting. The symptoms are associated with the brain and the sympathetic nervous system.

The symptoms are associated with the brain because the brain requires sufficient blood glucose for it to function normally. Very low blood glucose levels cause brain blood glucose insufficiency (neuroglycopenia].