Hyperglycemia, or high blood sugar, can negatively affect hospitalized patients who fail to produce sufficient insulin to metabolize the sugar contents of their blood. Aside from patients with diabetes, hyperglycemia can result from medical conditions. Stroke or myocardial infarction (heart attack) patients, patients who have problems with the thyroid, adrenal, pituitary gland, pancreas, and patients who undergo major surgeries may also go into a hyperglycemic state.

Initial signs of hyperglycemia include hunger, thirst, frequent urination and fatigue. Sustained high blood sugar levels have far greater impact. They may lead to skin infections and impaired healing, stomach and intestinal difficulties, and eventually eye, kidney, and nerve damage. The condition may damage blood vessels and the organs they support, resulting in blindness, heart attack, stroke and limb amputations.

Prolonged hyperglycemia also may lead to a condition known as ketoacidosis. Overwhelmed by sugar, the body ceases to produce insulin, or diabetic insulin therapies become ineffective. Fat, rather than sugar, is then broken down for fuel. This result is a buildup of toxic ketones: a byproduct of fat metabolism. The syndrome is characterized by a shortness of breath, fruity breath odor, and nausea. Ketoacidosis requires immediate medical attention. If left untreated, it may result in coma and/or death.

Hospitalized patients, whether or not they have diabetes, may be treated with insulin to keep their blood sugar levels under control. Today, new technologies have been introduced to optimize insulin dosing for patients who experience hyperglycemia.