Hyperglycaemic Hyperosmolar Syndrome (HHS)

Question 1

what is it?

Answer 1

relative insulin deficiency in combination with extra stress can lead to hyperglycaemia and dehydration which then causes osmotic diuresis

Question 2

what are the biochemical results of HHS

Answer 2

• Hypovolaemia
• Marked hyperglycaemia >30mmol/L
• No or mild ketonaemia <3mmol/L
• Bicarbonate >15mmol/L or venous pH >7.3
• Osmolarity >320 mosmol/kg
• Osmolarity = 2[Na] + urea + glucose (normal osmolarity is 275-295)
• Higher glucose than DKA (often > 50mmol/L but 30mmol/L is indicative)
• Renal impairment
• Sodium either high normal or raised
• Less ketogenic and acidotic than DKA

Question 3

who gets it?

Answer 3

diabetes generally not known at presentation
older patients or young Afro-Caribbean patients
high intake of refined carbohydrate intake before presentation
medication - steroids and thiazide diuretics
can be nderlying precipitants e.g. sepsis or CVD (stroke/MI)

Question 4

how is it managed?`

Answer 4

• Monitor and frequently measure plasma osmolarity
• Assess severity of dehydration and use 0.9% saline for fluid replacement – will help to reduce osmolarity
• No insulin generally
• Monitor and chart BG osmolarity and sodium
• Start low dose IV insulin only if significant ketones >1 or if BG is falling at a slow rate
• Prophylactic fragmin
• Identify underlying precipitants
• High risk of feet complications so check the feet (CPR)

Question 5

what type of DM is more associated?

Answer 5

Type 2

Question 6

what normally precipitates?

Answer 6

diuretics &/or steroids can increase risk
‘fizzy drinks’ can increase risk
new diabetes diagnosis or infection precipitates
source can often be another health event e.g. silent MI