Hyperosmolar Hyperglycaemic State

Question 1

What is hyperosmolar hyperglycaemic state (HHS)?

Answer 1

A severe complication of diabetes mellitus (predominantly type 2) characterised by extreme hyperglycaemia and hyperosmolality without significant ketosis.

Question 2

What are the key driver of hyperglycaemia in HHS?

Answer 2

Osmotic diuresis with associated loss of sodium and potassium.

Question 3

What physiological changes occur due to severe volume depletion in HHS?

Answer 3

Significant raise in serum osmolality leading to hyperviscosity of blood.

Question 4

What is the effect of hypertonicity in HHS?

Answer 4

Preservation of intravascular volume; patients may not appear as dehydrated as they are.

Question 5

What are the general clinical features of HHS?

Answer 5

• Fatigue
• Nausea
• Vomiting

Question 6

What neurological symptoms are associated with HHS?

Answer 6

• Altered consciousness
• Headaches
• Papilloedema
• Weakness

Question 7

What cardiovascular symptoms are present in HHS?

Answer 7

• Dehydration
• Hypotension
• Tachycardia

Question 8

What are the three key diagnostic criteria for HHS?

Answer 8

• Hypovolaemia
• Hyperglycaemia (>30mmol/L) with no significant ketosis or acidosis
• Raised serum osmolality (>320mosmol/kg)

Question 9

What are the management goals for HHS?

Answer 9

• Normalise osmolality (gradually)
• Replace fluids and electrolytes
• Normalise blood glucose (gradually)