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
Dunn et al. Chapter 49: Diabetic Emergencies. The Emergency Medicine Manual. 5th Edition. Vol 1
SJH Prescriber Capsule. Endocrinology. Hypoglycaemia