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Deteriorating Patient

Blood Sugar Level



  • The blood sugar should be tested in every acutely unwell person, mainly because hypoglycaemia is an underdiagnosed cause of reduced consciousness, and can mimic stroke symptoms.


  • A blood sugar level of ≤3.9 is generally considered to indicate hypoglycaemia. This is a clinical emergency and should be rapidly treated.
    • Causes of Hypoglycaemia

    • Diabetics

    • Insulin - excessive insulin dosing, regular insulin dosing despite reduced carbohydrate intake / missing a meal, use of an insulin infusion perioperatively without dextrose infusion
    • Oral hypoglycaemics - sulfonylureas
    • Non-Diabetics

    • Insulinoma
    • Symptoms

    • Autonomic (mild / moderate hypoglycaemia) - hunger, anxiety, diaphoresis, tremor, palpitations, paraesthesiae
    • Neuroglycopaenic (severe hypoglycaemia) - fatigue, confusion, visual changes, seizures, unconsciousness


    • Symptoms

    • Fatigue
    • Polyuria
    • Polydipsia
    • Thirst
    • Weight loss
    • Acute Complications

    • Diabetic ketoacidosis (DKA)
    • Hyperglycaemic hyperosmolar state (HHS)
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