Hypoxaemia in COVID-19 does not necessarily imply COVID pneumonia or post-COVID lung fibrosis, and the caveats of finger pulse oximetry should be remembered. Drug-induced methaemoglobinemia should be considered in individuals with unexplained cyanosis, refractory hypoxaemia, or the presence of a saturation gap. Here, we share our recent encounter of ‘spurious hypoxia’ in a patient with COVID-19 and methaemoglobinemia.
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