Diabetic ketoacidosis

• What is Diabetic Ketoacidosis
• Statistics on Diabetic Ketoacidosis
• Risk Factors for Diabetic Ketoacidosis
• Progression of Diabetic Ketoacidosis
• Symptoms of Diabetic Ketoacidosis
• Clinical Examination of Diabetic Ketoacidosis
• How is Diabetic Ketoacidosis Diagnosed?
• Prognosis of Diabetic Ketoacidosis
• How is Diabetic Ketoacidosis Treated?
• Diabetic Ketoacidosis References

What is Diabetic Ketoacidosis

Diabetic ketoacidosis (DKA) is the hallmark of type 1 (insulin-dependent) diabetes mellitus. DKA is an emergency condition caused by a disturbance in your body’s metabolism. Extremely high blood glucose levels, along with a severe lack of insulin, result in the breakdown of body fat for energy and an accumulation of ketones in the blood and urine.

Statistics on Diabetic Ketoacidosis

Diabetic ketoacidosis can occur in between 16%-80% of children presenting with newly diagnosed diabetes. It remains the most common cause of death for young type 1 diabetes sufferers. Before the discovery of insulin, mortality rates were up to 100%. Today, the mortality has fallen to around 2% due to early identification and treatment. Death is usually caused by cerebral oedema (swelling of the brain).
DKA is most common in type 1 diabetes sufferers but may also occur in those with type 2 diabetes mellitus. However, the latter group usually has at least some functioning insulin so suffer from another disorder called hyperosmolar non-ketotic coma (HONK).
DKA tends to occur in individuals younger than 19 years, the more brittle of type 1 diabetic patients. However, DKA can affect diabetic patients of any age or sex.

Risk Factors for Diabetic Ketoacidosis

People with diabetes lack sufficient insulin, a hormone the body uses to metabolise glucose (a simple sugar) for energy. Therefore in diabetic patients glucose is not available as a fuel, so the body turns to fat stores for energy. However when fats are broken down they produce byproducts called ketones which build up in the blood and can be damaging to the body. In particular, accumulated ketones can “spill” over into the urine and make the blood become more acidic than body tissues (ketoacidosis). Blood glucose levels also become very high due to the liver producing more glucose to try to combat the problem and because cells cannot take up that glucose without insulin.
The most common causes of this scenario are either a new diagnosis of diabetes or stresses to the body which alter the body’s insulin requirements in a known diabetic. Some examples of the latter include:

• Underlying infection, commonly pneumonia or urinary tract infection.

 

• Silent myocardial infarction
• Pancreatitis
• Stroke
• Drugs such as steroids or diuretics (fluid tablets).
• Non taking your insulin after you have already been diagnosed with diabetes.
• Surgery.As fore mentioned, young children and adolescents are more prone to developing ketoacidosis than adult patients with diabetes.In type 2 diabetics, diabetic ketoacidosis can be caused by severe stress to the body in conjunction with poor compliance with medication (not taking your medications as prescribed) and diet.
  

  Progression of Diabetic Ketoacidosis

  Diabetic ketoacidosis is a medical emergency that requires immediate hospitalisation to control the condition. Decreasing cell function due to decreased blood pH leads to organ failure. Patients can also lapse into a coma. Severe ketoacidosis can be fatal if left untreated.
  

  Symptoms of Diabetic Ketoacidosis

  If you are developing diabetic ketoacidosis you may notice a number of different symptoms. The most common early symptoms include excessive thirst, drinking lots of fluids, frequent urination and rapid weight loss. These are the classical symptoms of diabetes and excess blood sugar. These symptoms may then worsen into full blown diabetic ketoacidosis. In these cases you may notice:

  • General weakness.
    Fatigue.

   

• Dehydration.
• Nausea and vomiting.
• Loss of appetite .
• Confusion.
• Abdominal pain.
• Breathlessness or rapid breathing.
• A general ill appearance.
• Dry skin.
• Dry mouth.
• Increased heart rate.
• Sometimes a distinctive fruity odour on the breath.Your doctor will ask specific details about your symptoms including their onset and duration. They will also want to know if you have been previously diagnosed with diabetes and if applicable whether you have been taking your medications correctly.
  

  Clinical Examination of Diabetic Ketoacidosis

  Your treating doctor will carefully examine you paying attention to your vital signs (pulse, respiratory rate, blood pressure, temperature) and then each of your major systems. The diagnosis of DKA is usually apparent following history, examination and basic investigations. Remember that DKA is an emergency and requires urgent treatment which is normally commenced during your assessment.
  Some major signs of ketoacidosis your doctor will be looking for include:

  • A general ill appearance.
• Signs of acidosis- Shallow and rapid breathing, abdominal tenderness and altered consciousness.
• Signs of dehydration- Weak and rapid pulse, dry mouth, dry skin, reduced skin turgor and low blood pressure.
• Decreased reflexes.
• A distinctive fruity/acetone smell to the breath.
• Hypothermia.
• Signs of other illness such as heart attack, urine infection or pneumonia.
  

  How is Diabetic Ketoacidosis Diagnosed?

  Your doctor may perform a number of investigations to confirm the diagnosis of DKA and to check for any conditions that may have triggered the disorder. It is likely you will have a number of blood tests including a full blood count and measurement of blood sugar, potassium, sodium, and other electrolyte levels. Ketone levels and kidney function markers along with an arterial blood gas sample, which provides a determination of the blood acid concentration (pH), are also standard investigations.
  You may also need a chest x-ray, ECG, urine analysis, and possibly a CT of the brain to identify any sources of infection. If you develop altered consciousness during therapy, you may also need an MRI of the head to detect any cerebral oedema.
  

  Prognosis of Diabetic Ketoacidosis

  The metabolic changes associated with DKA have the potential to cause significant cell damage, illness or death. Some of the possible complications of DKA are listed below:

  • Complications from associated illnesses- For example infection, stroke, and heart attacks are possible.

   

• Cerebral edema (swelling of the brain) and >pulmonary oedema (fluid in the lungs)- These disorders more commonly result secondary to treatments for DKA. Excessive fluid replacement can cause fluid to accumulate in other cavities.
• Arrhythmias (abnormal heart rhythms)- These occur secondary to electrolyte abnormalities and the acidosis.
• Diabetic retinopathy– These changes have been reported both prior to and after treatment for DKA.Thankfully however many treatments have been developed to help reduce these risks. Today the overall prognosis of DKA is very good. With aggressive treatment, most people with diabetic ketoacidosis can expect complete recovery. Death is considered rare and only occurs approximately 2% of the time. The elderly, patients with severe presentation and those with other illnesses are at the greatest risk of severe consequences.
  

  How is Diabetic Ketoacidosis Treated?

  Diabetic ketoacidosis is an emergency and requires urgent medical attention, often in and intensive care setting. The goal of treatment is to correct the elevated blood glucose level by giving additional insulin (usually by an infusion into the vein over several hours), and to replace fluids and electrolytes lost through excessive urination and vomiting. You will require close monitoring including regular finger prick glucose measurements, vital observations, fluid charts, blood tests and ECG monitoring. You may need a catheter into the bladder to measure urine output accurately. Monitoring is essential as there is a very fine balance between the fluid and electrolyte levels in your body.
  In addition you may require further investigations for the cause of the attack of ketoacidosis (as described above). If infection is the cause you may require a course of antibiotics.
  When you are feeling lots better and able to eat you will be switched from an insulin infusion to subcutaneous injections. Particularly if this is your first presentation of diabetes you will need education about the disorder and how to prevent it in the future. It is important you understand the early warning signs of ketoacidosis such as excessive thirst, increased urination or lethargy. Your doctor will explain how to adjust your medications if this occurs. If you develop an illness or infection you should take the following steps to avoid ketoacidosis:

  • Frequently measure your blood glucose by finger prick test.
• If your glucose is higher than 16, measure the ketones in your urine. Elevated ketones and high sugar may suggest impending ketoacidosis so you should seek medical advice.
• Maintain your hydration by keeping your fluids consumption up.
• Continue or increase your insulin dose as prescribed by their doctor.
• Seek medical attention urgently if dehydration, persistent vomiting, or uncontrolled hyperglycemia develop.
  

  Diabetic Ketoacidosis References

  1. Australasian Paediatric Endocrine Group for the Department of Health and Ageing Clinical practice guidelines: Type 1 diabetes in children and adolescents, NHMRC, 2005.
• Hamdy O, Schade D. Diabetic Ketoacidosis, eMedicine, 2006. Available [online] at URL: http://www.emedicine.com/med/topic548.htm
• Kumar P, Clark M. Clinical Medicine. WB Saunders 2002 Pg 427-430.
• Longmore M, Wilkinson I, Torok E. Oxford Handbook of Clinical Medicine. Oxford University Press. 2001.
• Powers A. ‘Diabetes Mellitus’ in Braunwald, Fauci, Kasper, Hauser, Longo, Jameson, Harrison’s Principles of Internal Medicine, 16th Edition, McGraw-Hill, 2005.