What We Have Learned About COVID-19: Part One - Mass General Advances in Motion
►https://advances.massgeneral.org/pulmonary/article.aspx?id=1269
Happy Hypoxia: Not Hypoxia and Not New
Early in the outbreak, some reported that patients with #COVID-19 respiratory failure were presenting with hypoxemia that is out of proportion to the degree of dyspnea—a phenomenon termed (incorrectly) “happy hypoxia.” To the extent that this is a real phenomenon (most reports were anecdotal), the observation of hypoxemia without dyspnea should not be surprising (Tobin, Laghi and Jubran 2020) and is not unique to COVID-19. Indeed, an argument may be made that the widespread attention paid to this issue was more a function of the number of non-specialist providers seeing COVID-19 patients than it was of the virus itself. Since that time, corrective literature (Tobin, Laghi and Jubran 2020), which explains the established principles of respiratory physiology (Banzett et al. 1996; Burki and Lee 2010; Lansing, Gracely and Banzett 2009; Harold L. Manning et al. 1992) behind this phenomenon, has emerged. Dyspnea has a complex relationship to hypoxemia, and hypoxemia alone is a weak stimulus for dyspnea (H. L. Manning and Schwartzstein 1995) We cover the physiology at length in a prior two-part FLARE.