“…In addition, the combined effect of the destruction of membrane structures and the presence of a higher degree of oxidative stress in the RBCs of patients with COVID-19 [ 20 ], leads to the formation of metHb [ 281 , 282 , 283 , 284 , 285 , 286 ], unable to carry oxygen [ 88 , 90 , 287 , 288 ] and thereby the initiator of encephalopathy, the clinical manifestations of which (depending on the degree of metHb accumulation) [ 289 ] can vary from asymptomatic to severe hypoxia that does not respond to supplemental oxygen therapy, leading to changes in mental status, coma, and death [ 290 , 291 , 292 ].…”