Diabetic Ketoacidosis

Diabetic Ketoacidosis Vanessa Ting Ching Ching

Introduction • DKA is a serious acute complication of diabetes. • Characterised by hyperglycaemia, anion gap metabolic acidosis & ketonaemia

Pathogenesis

Precipitating Factors • • • • •

Inadequate/non-compliance with insulin therapy Infection Acute major illnesses (MI, CVA) New onset Type 1 diabetes Drugs affecting carbohydrate metablosim (glucocorticoids, high dose thiazides, sympathomimetic agents (dobutamine, dopamine), 2nd-generation antipsychotic agent • Cocaine use

Clinical Presentation • Rapid progression (usually over a few days) • Initially polyuria, polydipsia, nocturia & weight loss • Progress to Kussmaul respirations (compensatory hyperventilation for low arterial pH), fruity (acetone) breath, abdominal pain, vomiting • Hypovolaemia (dehydration, decreased skin turgor, dry axillae and oral mucosa, hypotension) • Drowsiness, lethargy & coma (neurologic disturbances due to plasma hyperosmolality) • Fever is rare even in infection due to peripheral vasoconstriction caused by hypovolaemia

Diagnosis • Hyperglycaemia (>14mmol/L) • Anion gap metabolic acidosis (pH<7.3, HCO3<15mmol/L) • Other investigations – Serum potassium: usually high (K+ movement into ECF & insulin deficiency) – Serum sodium: normal or low (usually of no concern) – WCC: raised; may be unrelated to infection (hypercortisolaemia) – Urea & creatinine: raised (dehydration

• Ketonaemia/ Ketonuria – 3 ketone bodies produced (beta-hydroxybutyric acid, acetoacetic acid, acetone)

Laboratory Findings • Hyperglycaemia • Hyperosmolality • ↑blood urea & creatinine (due to ↓GFR)

Fluid Replacement • For the 1st 24 hours, 6-8L may need to be given. Normal saline (0.9%) is initially used • Switch to half saline (0.45%) when Na>145mmol/L. Care must be taken not to reduce plasma osmolality too rapidly (cerebral oedema may occur) • Dextrose saline or 5% dextrose should be used when glucose level<15mmol/L • Blood urea, serum electrolytes and serum creatinine must be concurrently monitored.

Potassium Supplementation

Complications of Treatment

Patient Education • Insulin – compliance, skipped doses – Condition of insulin – cloudy, frosted vial, proper storage – Increased requirements due to illness/stress (infection, pregnancy, pancreatitis, trauma, hyperthyroidism, MI)

• Signs & symptoms – – – –

Hyperglycaemia – thirst, excess urination, fatigue, blurred vision Acidosis – fruity breath, deep & difficult breathing Dehydration – dry mouth, warm dry skin, fatigue Stomach pain, nausea, vomiting, decreased appetite

• Action to be taken – Drink plenty of fluids, continue taking insulin dose – Seek medical attention immediately