Hypoglycaemia - Complications of diabetes

Hypoglycaemia

Definition

Low serum glucose caused by insufficient hepatic glucose production for peripheral requirements.

Aetiology

Insulin overdose (accidental or deliberate self harm), sulphonylurea overdose, malnutrition, fasting, exercise or severe liver disease. Alcohol impairs gluconeogenesis and can cause hypoglycaemia in diabetic patients. Rare causes include insulinomas and Addison’s disease.

Clinical features

Patients become irritable, pale, weak and sweaty. In patients who have regular hypoglycaemic episodes and in autonomic neuropathy the awareness of symptoms is reduced. Untreated the condition progresses to confusion, seizures and coma. Prolonged or severe hypoglycaemia risks permanent neurological damage and death.

Investigations

The diagnosis can be confirmed on bedside blood sugar testing, a formal laboratory glucose sample should be sent but treatment should not be delayed. Other tests may be required to identify the underlying cause.

Management

This is a medical emergency and requires immediate treatment.

·        In conscious patients the blood sugar can be raised by oral administration of a sugary drink. This should be followed by a more complex carbohydrate to prevent a further rebound hypoglycaemia.

·        In unconscious patients or those unable to tolerate oral fluids blood sugar can be raised by administration of glucose gel to the gums (e.g. Hypostop), intravenous dextrose or intramuscular glucagon.

·        Further management depends on severity and the underlying cause.