Diabetic ketoacidosis is caused by an almost total lack of insulin in the blood. Since insulin allows the body to use glucose as an energy source, very low levels of insulin force the body to utilize other molecules for energy. These alternate metabolic processes create chemicals known as ketones, which can be toxic in high amounts.
Dehydration
One of the main symptoms of diabetic ketoacidosis is dehydration, the Mayo Clinic explains. Diabetic ketoacidosis is caused by the body being unable to use glucose as an energy source, forcing it to burn fat. This causes blood sugar levels to skyrocket. The kidneys are unable to filter out all of the glucose, leading it to appear in the blood. This causes the kidneys to excrete large volumes of fluid into the urine in an attempt to dilute the glucose. This excessive urination results in dehydration, which can cause a headache and extreme and persistent thirst. In infants, the dehydration may take the form of a constantly wet diaper.
Abdominal Symptoms
Patients who are experiencing diabetic ketoacidosis will also feel extreme nausea and vomiting, the American Diabetes Association states. Nausea and vomiting are nonspecific symptoms that can be caused by many diseases. Patients suffering from diabetic ketoacidosis, however, will experience prolonged nausea, which can lead to patients vomiting for two hours or longer. Not only may this be a sign of diabetic ketoacidosis, the vomiting may exacerbate the dehydration and make consuming fluids impossible. Diabetic ketoacidosis can also result in extreme abdominal pain and a loss of appetite.
Fruity Breath
Diabetic ketoacidosis can also lead to a characteristic fruity odor on the breath, the Merck Manual explains. The ketones in the blood often take the form of a chemical known as acetone. High levels of acetone in the blood cause some of it to evaporate into air from the lungs which is being exhaled. This acetone then gives the breath a fruit-like odor.
Cardiovascular
Patients who are experiencing diabetic ketoacidosis may also have extremely low blood pressure due to dehydration, combined with a very rapid heart rate as the heart attempts to keep blood flowing. Because the ketones produced by ketoacidosis are a weak acid, the blood can become unusually acidic. To compensate for this, many patients will breathe rapidly and deeply, as increased respiration can help lower the amount of acid in the blood.
Mental Symptoms
Patients suffering from diabetic ketoacidosis may become confused due to the buildup of ketones in the blood. Some patients may also develop swelling in the brain, which is also known as cerebral edema. This can cause severe headaches and changes in the patient's consciousness. If untreated, diabetic ketoacidosis can result in a coma and death.
