DKA

Diabetic Ketoacidosis (DKA) in Children

Diabetic ketoacidosis (DKA) is a serious and potentially life-threatening complication of type 1 diabetes mellitus (T1DM). It is a medical emergency that results from a severe lack of insulin, leading to dangerously high blood glucose levels and the production of acidic ketone bodies. It is a common presenting feature of new-onset T1DM in children.

Pathophysiology

In DKA, the absence of insulin prevents glucose from entering the body’s cells for energy. The body’s counter-regulatory hormones (glucagon, cortisol, catecholamines) respond by breaking down fat and muscle for energy. This process, known as lipolysis and proteolysis, produces ketone bodies and fatty acids. The accumulation of these acidic ketones in the blood leads to a metabolic acidosis.

Three key components define DKA:

1. Hyperglycaemia: Blood glucose $>11$ mmol/L.

2. Ketosis: Ketones in the blood (beta-hydroxybutyrate) $>3.0$ mmol/L or urine ketones $>2+$.

3. Metabolic Acidosis: A blood pH of $<7.3$ or bicarbonate level of $<15$ mmol/L.

    

Clinical Presentation

The symptoms of DKA can be non-specific and may develop over several days.

• Classic Symptoms of T1DM: Polyuria (frequent urination), polydipsia (excessive thirst), and weight loss.

• Abdominal Symptoms: Abdominal pain and vomiting are very common and can lead to a misdiagnosis of gastroenteritis or a surgical abdomen.

• Respiratory: Deep, laboured breathing (Kussmaul respiration) as the body tries to “blow off” carbon dioxide to correct the acidosis.

• Neurological: Drowsiness, confusion, and, in severe cases, reduced consciousness.

   

Management

Management of DKA is a paediatric emergency and should be carried out in a hospital setting with a clear protocol. The main aims are to correct dehydration, reverse acidosis, and normalise blood glucose.

Initial Assessment

• A-E Approach: Follow a structured Airway, Breathing, Circulation, Disability, Exposure (A-E) approach.

• Fluid Assessment: Assess the degree of dehydration.

• Investigations: Get an immediate blood gas to check pH, bicarbonate, and blood glucose.

   

Management Protocol

1. Fluid Resuscitation:

   • Start an intravenous fluid infusion (e.g., 0.9% saline) to correct dehydration and improve circulation.

   • Give a fluid bolus of 10 ml/kg of 0.9% saline for significant shock or hypotension.

      

2. Insulin Infusion:

   • Start a continuous intravenous insulin infusion (usually 0.05-0.1 units/kg/hour). Insulin should not be started until after the initial fluid resuscitation to avoid a rapid drop in blood glucose.

      
      

3. Electrolyte Management:

   • Monitor electrolytes closely, especially potassium.

   • Add potassium to the IV fluids once the potassium level is known and the child has started to pass urine.

      

4. Monitoring:

   • Monitor the child’s neurological status closely.

   • Monitor fluid input and output.

   • Monitor blood glucose, ketones, and electrolytes regularly.

Complications

The most feared complication of DKA is cerebral oedema, which can occur due to a rapid shift in fluid and electrolytes during treatment. The risk of cerebral oedema can be reduced by using a slow, steady fluid infusion and avoiding a rapid correction of blood glucose. Other complications include hypokalaemia and thrombosis.