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Deteriorating Patient
Deteriorating Patient

Blood Sugar Level

February 15th, 2021


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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