DKA (1*) Flashcards
Pathophysiology:
Why does Ketoacidosis occur?
Why does Dehydration occur?
Why does Hyperkalaemia occur?
→ Why shouldn’t insulin be started suddenly?
What is therefore the most important aspect in DKA management?
➊ Body enters a state of starvation, so it gets its energy from fat stores via ketogenesis. Ketone bodies are weak acids, which can lead to significant acidosis and severe illness in increasing quantities. Kidneys then produce Bicarbonate to try and buffer the ketones, but over time the ketones become too much → Acidosis
➋ Glycosuria draws water out into the urine in a process called Osmotic Diuresis → Polyuria and Polydipsia
➌ Lack of insulin means Potassium can’t be driven into cells
→ Pts can develop severe Hypokalaemia as lots of K+ is pushed into cells. This can lead to fatal Arrhythmias.
➍ Fluid resuscitation as its the these things that kill pts
How does it present?
How is it diagnosed?
➊ • Usually triggered by e.g. infection, non-compliance to meds, emotional/physical stress, dehydration
• Dehydration
• Polyuria, Polydipsia
• N+V
• Altered consciousness
• O/E – Kussmaul breathing, Fruity breath (Acetoacetone), Hypotension (may even go into hypovolemic shock)
➋ • Diabetes – > 11mmol/L
• Ketosis - > 3mmol/L
• Acidosis - < 7.3
Management:
What is the first thing to do?
→ Why shouldn’t this be done too quickly?
What should be done after this?
How else should it be managed?
➊ Fluid Resuscitation!
• Initial bolus of 10ml/kg 0.9% NaCl over 60 mins
• Add KCl in every 500 ml and monitor K closely
→ It increases the risk of cerebral oedema
➋ Fixed-rate Insulin infusion at 0.05-0.1units/kg/hour 1-2 hours after starting IVF
➌ • Monitor glucose, ketones, ph, gcs
• Avoid hypoglycaemia with dextrose if glucose falls < 4mmol/L
• Monitor for signs of cerebral oedema e.g. unequal pupils, lower GCS etc.
What’s the main complication that occur here during management?
→ Why does this occur?
→ How is this managed?
What other complications are there?
➊ Cerebral Oedema
→ Dehydration and Hyperglycaemia cause water to move out of brain cells, causing them to shrink. Rapid correction of this dehydration and hyperglycaemia causes lots of water to move into cells too quickly. This causes oedema and can lead to brain cell death.
→ IV Mannitol, Hypertonic Saline, or Slowing IVF
➋ Hypoglycaemia and Hypokalaemia
