Diabetic Ketoacidosis

Introduction

Diabetic ketoacidosis (DKA) is a condition associated with high blood glucose (usually > 18 mmol/L), which nonetheless, is unavailable to the body tissues as a source of energy.
Fat is therefore broken down as an alternative source of energy, releasing toxic chemicals called ketones as a by-product.
Additionally, there is severe dehydration and electrolyte imbalance in DKA, especially low potassium.
It is a common cause of death among diabetes patients in developing countries.
It often occurs in type 1 diabetes patients but may also occur in type 2 diabetes.
In contrast, the Hyperosmolar Non-Ketotic state (HONK) in diabetes occurs primarily in Type 2 patients, and is similar in its clinical presentation to diabetic ketoacidosis in many respects.
A major difference, however, is the absence of a significant amount of ketones in the urine (usually trace or 1+) and the presence of severe dehydration.
The management of this condition is similar to that of DKA.

Causes of diabetic ketoacidosis

The following are some of the known causes of diabetic ketoacidosis:

  1. Severe deficiency of insulin
  2. Interruption of anti-hyperglycaemic therapy (usually for financial reasons or for alternative treatment)
  3. Stress of intercurrent illness (e.g. infection, myocardial infarction, stroke, surgery, complicated pregnancy etc.)

Symptoms of diabetic ketoacidosis

The following are common symptoms of diabetic ketoacidosis:

  • Polyuria
  • Polydipsia
  • Nausea, vomiting
  • Abdominal pain
  • Alteration in sensorium or collapse
  • Symptoms of infection or other underlying condition

Signs of diabetic ketoacidosis

Signs of diabetic ketoacidosis include the following:

  • Dehydration (dry skin, reduced skin turgor or sunken eyes)
  • Deep and fast breathing
  • Fast and weak pulse
  • ‘Fruity’ breath (smell of acetone)
  • Confusion, stupor or unconsciousness
  • Evidence of infection, recent surgery, stroke etc.

Investigations

  • Random blood glucose (usually >18 mmol/L)
  • Urine glucose (usually >3+) Urine ketones (usually >2+)
  • Blood urea and electrolytes (usually low potassium, however if in renal failure urea and potassium may be high)
  • Blood film for malaria parasites
  • Full blood count (raised white cell count would suggest bacterial infection) Urine culture
  • Blood culture
  • Chest X-ray (for pneumonia).
  • Arterial blood gases
  • Electrocardiogram (to identify hypokalaemia, and in adult patients to exclude acute myocardial infarction as a precipitating factor)

Treatment of diabetic ketoacidosis

Treatment objectives

The treatment objectives of diabetic ketoacidosis include the following:

  1. To replace the fluid losses
  2. To replace the electrolyte losses, especially potassium
  3. To replace deficient insulin
  4. To seek the underlying cause and treat appropriately

Pharmacological treatment

A. Management of Diabetic Ketoacidosis (DKA)

Regime for managing Diabetic Ketoacidosis in AdultsĀ 

 

Regime for managing Diabetic Ketoacidosis in Children

Sample Sliding Scale Chart

Blood Glucose Result
(following 4-hourly testing)
Corresponding Dose of Regular Insulin to administer
Subcutaneously
Corresponding Dose of Regular Insulin to administer
Subcutaneously
mmol/LADULTSCHILDREN
< 6.0No InsulinNo Insulin
6.1 - 9.04 units0.06 units/kg
9.1 - 12.06 units0.09 units/kg
12.1 - 15.0 8 units0.12 units/kg
15.1 - 18.010 units0.15 units/kg

Note

The example of the sliding scale given above is not a fixed standard.
The requirement of insulin for each level of blood glucose measured differs from patient to patient.
The corresponding insulin doses may therefore need to be adjusted up or down to suit each patient.
For both adults and children, continue the sliding scale, making appropriate adjustments to the doses of insulin, until the patient is eating normally and the urine is free of ketones before changing to twice-daily intermediate or premixed insulin.
This may take on average 12-72 hours.

B. Management of Hyperosmolar Non-Ketotic State (HONK)

(See ‘Management of DKA’ above)

C. Adjunct Treatment for DKA and HONK

  • Broad-spectrum antibiotics for suspected infections (See appropriate section).
  • Treat malaria if suspected or confirmed (See appropriate section)

Referral Criteria

  • If there are inadequate resources for managing the patient, start 0.9% Sodium Chloride, IV, and give initial dose of soluble or regular insulin IV or IM after confirming blood glucose and urine ketone levels and refer to a nearby regional or teaching hospital.
  • If the patient remains comatose or fails to pass adequate amounts of urine despite management, refer to a regional or teaching hospital for further care.