By Victor 
Diabetic Ketoacidosis (DKA) is a life threatening acute complication of Diabetes Mellitus. It is common in type 1 diabetes but can occur in type 2 diabetes as well.
It often occurs in younger patients, develops over hours to days.
Signs and Symptoms of Diabetic Ketoacidosis (DKA)
- Vomiting
- Abdominal cramps
- Body weakness
- Dehydration
- Acidotic breathing
- Coma or seizures
- High blood sugar but usually <40mmol/L
- Ketonuria
- Blood ketones positive
- Serum osmolality < 350mOsm/L
Diagnostic criteria
Presence of the following features are enough for diagnosis of DKA:
- Hyperglycemia
- Ketonuria or positive serum ketones
- Metabolic Acidosis on Arterial Blood Gas (ABG) or venous blood gas
General Measures
For All patients:
- St up two large intravenous lines
- Protect airway and insert nasogastric tube if unconscious
- Monitor urine output
- Monitor plasma glucose, ketones, urine, and electrolytes on venous blood gas
- Look for precipitating factors such as infection (e.g. respiratory infection) and MI.
Medicine Treatment
Medicine treatment of diabetic ketoacidosis (DKA) is divided into 5 main areas of focus:
- Fluid management
- Insulin therapy
- Electrolyte correction
- Monitoring
- Additional treatment
Fluid management
Average fluid deficit in adults is about 6L, may be as much as 12L.If renal or cardiac disease is present, monitor with central venous pressure.
In the absence of renal or cardiac compromise:
- NaCL 0.9% (normal saline), IV 15 to 20ml/kg in the first hour. For patients < 20 years rate is 10-20ml/kg.
- Subsequent rate varies from 5 to 5ml/kg/hour depending on the clinical condition.
- Correction of estimated deficits should take place over 24 hours.
- The volume infused in the first 4 hours should not be more than 50ml/kg.
- Fluid therapy is thereafter calculated to replace estimated deficit in 48 hours, ±5ml/kg/hour
- Reduction in serum osmolality should not exceed 3 mOsm/kg/hour
Electrolyte Correction
Correct plasma sodium value for blood glucose:
- Divide glucose value by three then add sodium value, the formula is below.
- Corrected Na+= [blood glucose ÷ 3 ] + Na+
If plasma sodium Na+ > 140:
- Use hypotonic saline (NaCl 0.45%), IV as fluid replacement
If plasma Na+ ≤ 140:
- Use Normal saline (NaCl 0.9%), IV as fluid replacement
If plasma glucose is less than 15mmo/l but ketones still present:
- Replace change fluids to Dextrose 5% or Dextrose 10% in sodium chloride 0.9%, IV.
Adjust fluid volume and rate accordingly, cerebral oedema may occur with over-aggressive fluid replacement or rapid sodium change.
For Potassium use KCL:
- Add 40mmol in each 1L of fluids if serum potassium < 3.5
- Add 20mmol in each litre of fluids if serum potassium is 3.5-5.5 mmol/l
- Do not add any KCL if potassium > 3.5mmol/l
- Maximum K+ dose is 40mmol/hour
Monitor potassium hourly initially, then 2 hourly when stabilized.
Insulin therapy
Patients should be managed with continuous intravenous insulin or hourly intramuscular injections in a high care setting with appropriate monitoring.
Continue insulin therapy until acidosis and ketones have resolved.
Continuous intravenous insulin infusion instruction:
- Add 50 units of short acting insulin in 200ml NaCl.
- This means each 4ml solution = 1 unit insulin.
- Initial infusion is 0.1 units/kg/hour
- This translates to roughly 5 to 7 units/hour or 20-28ml/hour infusion rate.
- If blood sugar does not fall by 3 mmol/L in the 1st hour, double the rate.
- Expected plasma glucose drop is 3-4mmo/L/hour
- If plasma glucose < 14 mmol/L, reduce insulin infusion rate to 1-2 units per hour (4-8ml/hour).
Hourly intramuscular injections (if no fluid rate regulator machine available):
- Dilute 100units of Short Acting insulin in 9 ml NaCl to make 10 units/ml solution.
- Loading dose is 0.5 units/kg
- Give half dose IM and half dose IV as bolus. Do not use insulin syringe or needle for IM injection.
- Subsequent hourly doses: ±5-10 units IM hourly (0.1 units/kg/hour)
Monitoring in Diabetic Ketoacidosis
The following close monitoring is needed:
- Urine output hourly: expected output is at least 0.5ml/kg/hour
- Blood glucose hourly
- Potassium on blood gas 2-4 hourly
- Acidosis on venous blood gas 4 hourly
- Ketones in urine 4 hourly
- Ketones in serum
Additional Management
For all patients with Diabetic Ketoacidosis heparin must be given while in ward as follows:
- Give Enoxaparin 40 mg, SC, daily. OR
- Unfractionated heparin 5 000 units, SC, 12 hourly.
The above mentioned management should continue until the patient is out of acidosis and:
- Ketones have cleared
- Patient is able to eat
All patients with DKA should be started on insulin therapy as a long term treatment once DKA resolves, including type 2 diabetes patients.