Information
Editors
Diabetic Ketoacidosis
Essentials
- Always remember to measure plasma/blood glucose in patients showing unclear symptoms of any kind.
- Check for an acute disease needing treatment as the reason for plasma glucose increase.
- Ketoacidosis must always be treated in hospital. If the hyperglycaemic, non-ketotic patient is not admitted to hospital for observation, make sure that
- the patient is given insulin and fluids
- the plasma glucose begins to decrease.
- the patient is able to take care of himself and gets immediate help if he feels any worse.
- The reason for ketoacidosis should always be investigated and the patient's knowledge and skills regarding the management of his/her underlying disease checked (children, see Newly Diagnosed Type 1 Diabetes in a Child).
The most common reasons for ketoacidosis
- The cause of diabetic ketoacidosis is a lack of insulin which can be due to
- recent onset of diabetes
- interruption of insulin treatment for any reason
- acute infection
- sudden (acute) severe illness such as myocardial infarction
- insulin pump failure
- ineffective/spoiled insulin.
- Patients on insulin pump therapy develop ketoacidosis within a few hours e.g. in the event of insulin pump malfunction if alternative insulin administration methods are not used quickly enough, since the insulin used in the pumps is rapid-acting and is not stored under the skin.
Symptoms and findings
- Thirst
- Diuresis
- Nausea
- Stomach pain
- Chest pain
- Tachycardia
- Weight loss (undiagnosed or poorly controlled diabetes)
- Fever (infection)
- Reduced consciousness
- Deep hyperventilation (Kussmaul's respiration)
- Smell of acetone in breath
Laboratory findings
- Plasma glucose usually > 15 mmol/l. Note! Ketoacidosis should already be suspected at lower glucose levels in patients who are pregnant or in poor health condition. Ketoacidosis appears at lower than usual glucose levels also in patients who take SGLT2 inhibitors due to the mechanism of action of these drugs.
- Blood ketones are moderately elevated (possible to detect by rapid test). Determining urinary ketones is no longer recommended.
- Metabolic acidosis in blood gas analysis (Astrup). Note: in compensated acidosis the pH is normal, but BE < -2.5
Tests and treatment
Clinical examinations to find infection sites
- Auscultation of lungs
- Skin, especially between the toes and on the legs (erysipelas)
Laboratory tests
- Plasma glucose
- Plasma sodium and potassium
- Urine strip tests and culture
- CRP and blood leukocytes if there are signs of infection
- Acid-base balance, if available
- Plasma creatinine
- Plasma ionized calcium, magnesium, phosphate
- ECG and troponin as needed
- Chest x-ray
Treatment with fluids
- Give isotonic (0.9%) NaCl solution. If the patient has plasma sodium > 134 mmol/l, a 0.45% NaCl solution or Ringer solution should be given.
- 1 000 ml during the first 30-60 minutes
- About 500 ml/hour (4-14 ml/kg/hour, depending on the severity of dehydration), until blood glucose is < 12 mmol/l, after which the infusion is continued with 5% glucose solution.
- For the elderly and patients with heart failure the dosing should be more cautious, adjusted to the patient's condition and response, being approx. 50% of the aforementioned doses.
Treatment with insulin
- Rapid-acting insulin is given as intravenous infusion or once an hour intramuscularly (the effectiveness of subcutaneous absorption is uncertain).
- Continuous intravenous infusion is primarily used (no boluses because of the short half-life of insulin).
- Starting dose 0.15 units/kg
- Continuing with intravenous infusion 0.1 units/kg/hour
- If needed, the infusion rate may be adjusted so that plasma glucose concentration is reduced by 2 mmol/l/hour.
- Insulin may be administered as follows:
- Insulin solution in an infusion pump: 49.5 ml 0.9 % NaCl + 50 units (0.5 ml) rapid-acting insulin, resulting in an insulin concentration of 1 units/1 ml
- Insulin solution in an infusion controller: 99 ml 0.9 % NaCl + 100 units (1 ml) rapid-acting insulin, resulting in an insulin concentration of 1 units/ml (1 ml = 20 gtt)
- If intravenous infusion is not possible, rapid-acting insulin is administered intramuscularly.
- Starting dose 10-20 units
- Continuing with 0.1 units/kg every hour
- Plasma glucose monitoring hourly
Treating acidosis
- Acidosis is normally corrected by giving insulin and fluid therapy. The treatment of severe acidosis (pH < 7.0) with bicarbonate requires checking the dosing and by observing the response by following the acid-base balance (Astrup).
The prevention and treatment of potassium depletion
- Plasma potassium < 3.0 mmol/l: give potassium concentrate/chloride 35 mmol/hour added to the infusion solution. Note that insulin treatment may be started when plasma potassium concentration is > 3.3 mmol/l.
- Plasma potassium 3.0-4.0 mmol/l: potassium substitution 25 mmol/hour
- Plasma potassium 4.0-5.3 mmol/l: potassium substitution 20 mmol/hour
- Plasma potassium > 5.3 mmol/l: no potassium substitution
- Electrolyte concentrations monitored every 1-2 hours
- Important:Because of the risk of arrhythmia potassium must not be infused rapidly as a pure concentrate.
- Continuation of potassium substitution 1-3 g/day orally is often needed for a few days after stopping infusion.