Diabetic Emergencies

Question 1

List some common causes of hypoglycaemia

Answer 1

• Drugs (sulfonylureas, gliptins)
• Exercise
• EtOH
• Carb miscounting
• Diabetic lipodystrophy (scarring at site of continuous injection)

Question 2

How might you manage a patient with hypoglycaemia on presentation?

Answer 2

• Conscious?
  
  • Quick-acting carbs (5 jelly beans raises BGLs 2 mmol)
  • Long-acting carbs (sandwich, fruit etc.)
• Unconscious?
  
  • Glucagon - pre-filled syringes raise BGLs around 5 mmol
  • IV dextrose - 10 mL of 50%

Question 3

How might you manage a patient presenting with diabetic ketoacidosis?

Answer 3

• Rehydration
  
  • 1L stat, 1L over next 30 min, 1L over next hour
  • Change to 5% dextrose when BGLs below 12
• Correct potassium
  
  • Do not give insulin until K+ is known as it can cause intracellular shifts and hypokalaemia
  • Maintain between 3.5 and 5 mM
  • If less than 3.5 mM hold off on glucose and give 30 mM per hour until K+ within normal range
• Insulin therapy
  
  • 6-8 units hourly IV then adjust according to BGLs
  • Only lower BGLs by 2-5 mM per hour, give dextrose if too fast.
  • Hold levels around 10-15 once reached, else risk of proliferative retinopathy
• Correct underlying cause

Question 4

How might you manage a patient presenting with hyperosmotic non-ketotic coma?

Answer 4

• Fluids
  
  • 2L 0.45% saline over 3 hours, then 1L 2-3 hourly
  • Monitor urine output
• Insulin, potassium correction

Question 5

What are the two most important equations used in diabetic emergencies?

Answer 5

• Serum osmolality
  
  • 2(K+ + Na+) + glu + urea
  • Normally 280-295 mOsm (>330 in HONK)
  • In DKA, high IV osmolality shifts fluid to IV space, causing an apparent dilution of electrolytes
• Corrected sodium
  
  • Glu/4 + Na+
  • Corrects for apparent dilution