SAQ 373 – Endocrinology – myxoedema coma

Endocrinology – myxoedema coma.

a. Differentials

• Neurological: seizure or intracranial haemorrhage.
• Endocrine: adrenal insufficiency.
• Infective: sepsis, meningitis, or encephalitis.
• Environmental hypothermia.
• Toxicological: opioids, barbiturates, or valproate overdose.

b. Triggers

• Hypothermia, with higher incidence in winter.
• Infection, especially pneumonia, UTI, or cellulitis.
• Cerebrovascular event.
• Acute myocardial ischaemia.
• Trauma.
• Medications such as amiodarone, lithium, anaesthetic agents, or diuretics.

c. Treatment

• Replace thyroid hormone with levothyroxine 200-400 microg IV loading, then 50-100 microg daily.
• Give triiodothyronine 5-20 microg IV, then 2.5-10 microg every 8 hours.
• Give hydrocortisone 50-100 mg QID.
• Provide supportive care: IV fluid replacement and vasopressors/inotropes such as noradrenaline, adrenaline, or dobutamine aiming MAP 65 mmHg.
• Correct electrolytes, including IV calcium gluconate 10 mL of 10% for hypocalcaemia.