Methaemoglobinaemia – True Blue

Author: Frances Balmer / Editor: Jason Kendall / Reviewer: Rebecca Ford, Frances Balmer / Codes: A1, A4, PP2, R2 / Published: 16/05/2022

Methaemoglobinaemia is a life-threatening cause of hypoxia and death but is reversible with early recognition and treatment. This session provides an understanding of the underlying pathophysiology and causative agents, discusses how to identify and assess the patient with methaemoglobinaemia, and provides an evidence-based guide to treatment in line with the National Poisons Information Service and best practice.

Learning Objectives:

  • Understand the pathophysiology and clinical manifestation of methaemoglobinaemia
  • Recognise the need to screen for underlying causes of methaemoglobinaemia and modifying treatment according to cause
  • Appreciate the effect of methaemoglobin on oximetry and the limitations of SpO2 monitoring
  • Be able to perform risk stratification to identifying those patients who need active treatment
  • Gain a detailed knowledge of the pharmacological profile and risk/benefits of methylene blue use to facilitate safe prescribing


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