Hyperglycaemic hyperosmolar state (HHS) Flashcards
Define HHS.
What is the pathogenesis?
Relative insulin deficiency with high BM but normal ketones.
What are the symptoms of HHS?
HHS comes on over many days, and consequently, the dehydration and metabolic disturbances may be more extreme:
- consequences of volume loss - clinical signs of dehydration; polyuria; polydipsia
- systemic - lethargy, nausea and vomiting
- neurological - altered level of consciousness; focal neurological deficits
- haematological - hyperviscosity (may result in myocardial infarctions, stroke and peripheral arterial thrombosis)
How do you diagnose HHS?
- hypovolaemia
- marked hyperglycaemia (> 30 mmol/L)
- significantly raised serum osmolarity (> 320 mosmol/kg)
- can be calculated by: 2 * Na+ + glucose + urea
- no significant hyperketonaemia (< 3 mmol/L)
- no significant acidosis (bicarbonate > 15 mmol/l or pH > 7.3 – acidosis can occur due to lactic acidosis or renal impairment)
There are no precise diagnostic criteria though.
What is the osmolarity equation?
2(Na +K) + urea + glucose = osmolarity
normal = ~ 300mosm/L
What is the management of HHS?
Fluid resuscitation - may be deplete by 20-50% of body weight. Initially normal bloods as glucose draws water into vessels.
- fluid losses in HHS are estimated to be between 100 - 220 ml/kg
- give 0.5-1L/hr
- monitor K and add to fluids as needed
- sodium may rise as glucose falls
Insulin rarely needed - give only if necessary i.e. if glucose stops falling despite increasing fluids, give 0.05units/kg/hr
VTE prophylaxis
In HHS which of the following is false?
A serum bicarb is above is above 15
B patients are profoundly dehydrated
C VTE is far more likely
D patients are usually severely acidotic
E Blood sugars tend to be higher than in DKA
D
What are some triggers or HHS?
Illness
Dementia
Sedative drugs
What are the complications of HHS?
MI
Stroke