Hypoglycaemia

Introduction

Hypoglycaemia is a medical emergency. It can be lethal due to neuronal damage if prolonged and untreated.

 

Any patient with confusion or an altered level of consciousness must have hypoglycaemia out ruled as a cause. Not all patients who have hypoglycaemia have diabetes.

 

Causes

  • Drug induced

    • Insulin, Oral Hyperglycaemic Agents, ETOH

  • Inadequate food intake especially if combined with exercise

  • Sepsis

  • Status Epilepticus

    • (Hypoglycaemia can also cause the seizure)

  • Endocrine

    • adrenal insufficiency, pituitary failure, insulinoma

  • Liver Failure

Clinical Features

 

Symptoms

  • Palpitations, anxiety, hunger, fatigue, confusion

  • Many don’t get warning symptoms

Signs

  • Increased Sympathetic Activity

    • Sweating, tachycardia, pallor, dilated pupils

  • CNS Signs

    • Confusion, altered conscious state, tremor, parasthesia, seizure, slurred speech, weakness

 

Differential Diagnosis

  • CNS

    • Stroke, Infection, Trauma, Seizure, Migraine, Tumour

  • Cardiac

    • Acute MI, Tachyarrhythmia, Syncope

  • Sepsis

  • Metabolic

    • Hyponatraemia

Clinical Investigations

Bedside

  • Finger Prick BM < 4.0mmol

    • is all that is required to make the diagnosis.

  • VBG

    • Gives BM and other info e.g. metabolic disturbance, lactate, Na + K

Other investigations are targeted at finding the cause or excluding alternative diagnosis

Treatment & Disposition

 

Initial Resuscitation

  • Address ABC as clinically indicated

    • Hypoglycaemia may be cause of reduced consciousness, threatened airway or seizure.

    • Therefore BM should  be checked as matter of urgency while resuscitation is occurring

Specific Treatment

Conscious and able swallow

  • 15-20g of PO fast acting carbohydrate e.g. fruit juice, glucose gel or tablet

  • If repeat BM < 4 repeat above

  • If BM increases to > 4 follow with long acting carbohydrate e.g. 2 x biscuit

Unconscious or unable swallow

  • IV access and 75ml IV glucose 20% or 150ml glucose 10%

  • If unable obtain IV access give Glucagon 1mg IM

  • If repeat BM < 4 repeat above

  • Once alert ensure PO carbohydrate

Seek and treat any underlying cause

Disposition

  • If patient is well post treatment, has explained cause and has someone at home to keep an eye on them they can be discharged from the ED with GP follow up

  • If recurrent episodes, treatment resistant, underlying cause requiring treatment or no safe discharge plan patient should be admitted to hospital for ongoing treatment/observation

 

References

  1. Dunn et al. Chapter 49: Diabetic Emergencies. The Emergency Medicine Manual. 5th Edition. Vol 1

  2. SJH Prescriber Capsule. Endocrinology. Hypoglycaemia

Before you go have another look at the clinical case and see have your answers to any of the questions changed and if so how?