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?

Case 2