In a normally functioning human body, the pancreas produces insulin, a hormone that helps break down a certain type of sugar, glucose, so that it can leave the bloodstream and enter the cells of various organs. If a person has diabetic hyperglycemia, insulin does not remove glucose from the blood stream, and the blood sugar level becomes elevated beyond normal levels. The cause of diabetic hyperglycemia varies, usually depending on the type of diabetes someone has. For instance, if a person has type 1 diabetes and neglects to give himself enough insulin, his blood sugar will rise, because his body is unable to produce insulin on its own. Someone with type 2 diabetes may eat too much and experience diabetic hyperglycemia because her body has become resistant to insulin.
Ideally, a person's blood sugar stays below 130 milligrams per deciliter (mg/dL) of blood when he has not eaten and under 140 mg/dL after a meal. Diabetic hyperglycemia can be measured either while a person fasts or after a meal. Fasting hyperglycemia is a blood sugar level over 130 mg/dL, while after-meal hyperglycemia is blood sugar over 180 mg/dL.
Someone with diabetic hyperglycemia may not known her blood sugar is elevated unless she constantly monitors it, as symptoms usually do not occur until the levels reach 200 mg/dL. Common symptoms of diabetic hyperglycemia include increased thirst, headaches, and the frequent need to urinate. If a person does not get his blood sugar under control, hyperglycemia can worsen. Signs of an advanced case of hyperglycemia include an unusual, fruity breath odor, trouble breathing, and vision problems.
Diabetic hyperglycemia can also lead to a buildup of ketones, toxic acids produced in the blood when the body uses fat for energy. When the level of ketones in the blood becomes high, they move into the urine as well. Usually, the body will flush the ketones out in the urine. If the level is too high, it can lead to ketoacidosis, which can cause a diabetic coma.
Diabetic hyperglycemia can usually be controlled through exercise and diet. A person should avoid exercise if she has elevated ketone levels, as physical activity may then make the blood sugar level increase. Diabetics should monitor their blood sugar closely and talk with their doctor about making dietary changes if it is constantly above normal levels. Some people may need medication to keep their blood sugar levels under control.