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Updated: Dec 7, 2025

A Model to Simulate Clinically Relevant Hypoxia in Humans
Published on: December 22, 2016
Misconceptions of pathophysiology of happy hypoxemia and implications for management of COVID-19
Martin J Tobin1, Amal Jubran2, Franco Laghi2
1Division of Pulmonary and Critical Care Medicine, Hines Veterans Affairs Hospital and Loyola University of Chicago Stritch School of Medicine, Hines, IL, 60141, USA. mtobin2@lumc.edu.
Abstract:
In the article "The pathophysiology of 'happy' hypoxemia in COVID-19," Dhont et al. (Respir Res 21:198, 2020) discuss pathophysiological mechanisms that may be responsible for the absence of dyspnea in patients with COVID-19 who exhibit severe hypoxemia. The authors review well-known mechanisms that contribute to development of hypoxemia in patients with pneumonia, but are less clear as to why patients should be free of respiratory discomfort despite arterial oxygen levels commonly regarded as life threatening. The authors propose a number of therapeutic measures for patients with COVID-19 and happy hypoxemia; we believe readers should be alerted to problems with the authors' interpretations and recommendations.
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