Diabetic hyperglycemic hyperosmolar coma is a complication of type 2 diabetes that involves extremely high blood sugar (glucose) levels without the presence of ketones. Ketones are a by-product of fat breakdown.

This condition is usually seen in people with type 2 diabetes. It may occur in those who have not been diagnosed with diabetes, or in people who have not been able to control their diabetes with diet and medications.

The condition may be brought on by an infection, or by certain medications that lower glucose tolerance or increase fluid loss.

Normally, the kidneys make up for high glucose levels in the blood by allowing the extra glucose to leave the body in the urine. However, when water is scarce, the kidneys conserve (save) fluid, and glucose levels become higher. This results in a greater need for water.

Hyperosmolarity is a condition in which the blood has a high concentration of sodium, glucose, and other substances that normally cause water to move into the bloodstream. When the kidneys are conserving water, however, this creates a cycle of increasing blood-glucose levels and dehydration.

Risk factors include:

• A stressful event such as infection, heart attack, stroke, or recent surgery
• Congestive heart failure
• Older age
• Poor kidney function
• Poor management of diabetes -- not following the treatment plan as directed
• Stopping insulin or other medications that lower glucose levels

• Coma
• Confusion
• Convulsions
• Increased thirst
• Lethargy
• Nausea
• Weakness

Symptoms may get worse over a period of days or weeks.

Other symptoms that may occur with this disease:

• Dysfunctional movement
• Loss of feeling or function of muscles
• Speech impairment

Signs may include:

• Extreme dehydration
• High temperature -- higher than 38 degrees Centigrade (100.4 degrees Fahrenheit)
• Increased heart rate
• Low systolic blood pressure

Tests results include:

• High blood glucose
• High serum osmolarity
• Higher than normal serum sodium

Evaluation for possible causes may include:

• Blood cultures
• Chest x-ray
• Electrocardiogram (ECG)
• Urinalysis

The goal of treatment is to correct the dehydration. This will improve the blood pressure, urine output, and circulation.

Fluids and potassium will be given through a vein (intravenously). High glucose levels are treated with intravenous insulin.

The death rate with this condition is as high as 40%.

• Acute circulatory collapse (shock)
• Blood clot formation
• Brain swelling (cerebral edema)
• Increased blood acid levels (lactic acidosis)

This condition is a medical emergency. Go to the emergency room or call the local emergency number (such as 911) if you develop symptoms of diabetic hyperglycemic hyperosmolar coma.

Controlling type 2 diabetes and recognizing the early signs of dehydration and infection can help prevent this condition.

Cydulka RK, Pennington J. Diabetes Mellitus and Disorders of Glucose Homeostasis. In: Marx JA, Hockberger RS, Walls RM, Adams JG. Marx: Rosen's Emergency Medicine: Concepts and Clinical Practice. 6th ed. Philadelphia, Pa:Mosby, Inc.;2006:chap 124.