ISSN: 0034-8376
eISSN: 2564-8896






Detection of Pulmonary Shunts by Transcranial Doppler in Hospitalized Non-mechanically Ventilated Coronavirus Disease-19 Patients



Jaime L. I. Salazar-Orellana, Department of Neurology and Psychiatry, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (INCMyNSZ), Mexico City, Mexico
Miguel García-Grimshaw, Department of Neurology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
Sergio I. Valdés-Ferrer, Department of Neurology and Psychiatry, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (INCMyNSZ), Mexico City, Mexico; Center for Biomedical Science, Feinstein Institute for Medical Research, Manhasset, New York, USA
Sergio M. Alday-Ramírez, Department of Internal Medicine Western University, London, Ontario, Canada
Eduardo Ríos-Argaiz, Department of Internal Medicine Western University, London, Ontario, Canada
Zuilma Vasquéz-Ortiz, Cardiolology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
Eduardo Rivero-Sigarroa, Department of Critical Care Medicine, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
Amado Jiménez-Ruiz, Department of Neurology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
Erwin Chiquete, Department of Neurology and Psychiatry, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
Carlos Cantú-Brito, Department of Neurology and Psychiatry, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
Fernando D. Flores-Silva, Department of Neurology and Psychiatry, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico


In severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated disease coronavirus disease 2019 (COVID-19), hypoxemia mechanisms differ from those observed in acute respiratory distress syndrome. Hypoxemia and respiratory failure in COVID-19 are attributed to pulmonary angiopathy, increasing physiological pulmonary shunting1-3. Contrast-enhanced transcranial Doppler (TCD) with agitated saline of middle cerebral arteries (MCA) is a non-invasive method with a higher sensitivity for detecting right-to-left shunts than contrast-enhanced echocardiography4. TCD has been used to detect intrapulmonary shunts in COVID-19 patients undergoing invasive mechanical ventilation (IMV)5. We studied the relationship between intrapulmonary shunting, disease severity, and in-hospital outcome in COVID-19 patients not undergoing IMV (non-IMV).



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