Alternate Names: Nonketotic hyperglycemic coma; NKHHC

Causes and Risks:

Diabetic hyperglycemic hyperosmolar coma is a condition characterized by decreased consciousness, extreme dehydration, and extremely high blood-glucose levels that is not accompanied by ketoacidosis. The condition is usually seen in noninsulin-dependent diabetes and may occur in those previously undiagnosed, or those who have neglected their diabetes. The condition could be precipitated by an infection or by certain medications that impair glucose tolerance or increase fluid loss.

Normally the kidneys compensate for high glucose levels in the blood by excreting excess glucose in the urine. However, when dehydration occurs, the kidneys conserve fluid and glucose levels become higher (which results in greater dehydration).

Hyperosmolarity is a condition in which the blood is concentrated with sodium, glucose, and other molecules which, attracts water into the blood stream as a result. This creates a vicious cycle of increasing dehydration and increasing blood-glucose levels.

Risk factors are older age; underlying kidney insufficiency; congestive heart failure; recent discontinuation of insulin or oral hypoglycemic agents; and a precipitating event such as infection, heart attack, stroke, or recent surgery.

Prevention: Good control of noninsulin-dependent diabetes, recognition or early signs of dehydration and infection aid in prevention.

Symptoms:

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

• Speech impairment
• Muscle function/feeling loss
• Movement, dysfunctional

Signs and Tests: Vital signs (temperature, pulse, rate of breathing, blood pressure):

• Temperature greater than 38 degrees Centigrade (100.4 degrees Fahrenheit)
• Heart rate, greater than 100
• Systolic blood pressure, low (less than 100)

• Blood glucose, severely elevated (from 600 to 2,400 milligram/deciliter)
• Elevated serum osmolality test
• Elevated serum sodium

Treatment: The goal of treatment is to correct the dehydration which will correspondingly improve the blood pressure, low urine output, and poor circulation. Fluids and potassium are replaced by intravenous therapy. High glucose levels are treated with a short acting insulin preparation.

Prognosis: The death rate associated with this condition is up to 40%.

Complications:

• Acute circulatory collapse
• Thromboembolic events
• Cerebral edema
• Lactic acidosis

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