Hyperosmolar Hyperglycaemic State Flashcards
What is HHS?
-Medical emergency that can be difficult to manage and has a significant associated mortality (up to 20%).
-Hyperglycaemia results in osmotic diuresis, severe dehydration, and electrolyte deficiencies.
-HHS typically presents in the elderly T2DM
Pathophysiology of HHS
-Hyperglycaemia → ↑ serum osmolality → osmotic diuresis → severe volume depletion
Precipitating factors in HHS
-Intercurrent illness
-Dementia
-Sedative drugs
Clinical features of HHS
-Onset over many days
=more extreme dehydration and metabolic disturbances
-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)
Diagnostic criteria (typical features)
-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)
Management of HSS
-Fluid replacement
=Weight, fluid loss, osmolality
=Fluid losses in HHS are estimated to be between 100 - 220 ml/kg
=IV 0.9% sodium chloride solution
=Typically given at 0.5 - 1 L/hour depending on clinical assessment
=Potassium levels should be monitored and added to fluids depending on the level
-Insulin (Actrapid 0.05units/kg/hr IV)
=Should not be given unless blood glucose stops falling while giving IV fluids/ significantly ketonaemia
-Venous thromboembolism prophylaxis
=Patients are at risk of thrombosis due to hyperviscosity
Complications of HHS
-Vascular complications may occur due to hyperviscosity:
=Myocardial infarction
=Stroke
