Objective: To compare gas exchange indices behavior by using liberal versus conservative oxygenation targets in patients with moderate to severe acute respiratory distress syndrome secondary to COVID-19 under invasive mechanical ventilation. We also assessed the influence of high FiO 2 on respiratory system mechanics. Methods: We prospectively included consecutive patients aged over 18 years old with a diagnosis of COVID-19 and moderate-severe acute respiratory distress syndrome. For each patient, we randomly applied two FiO 2 protocols to achieve SpO 2 88% – 92% or 96%. We assessed oxygenation indices and respiratory system mechanics. Results: We enrolled 15 patients. All the oxygenation indices were significantly affected by the FiO 2 strategy (p < 0.05) selected. The PaO 2 /FiO 2 deteriorated, PA-aO 2 increased and Pa/AO 2 decreased significantly when using FiO 2 to achieve SpO 2 96%. Conversely, the functional shunt fraction was reduced. Respiratory mechanics were not affected by the FiO 2 strategy. Conclusion: A strategy aimed at liberal oxygenation targets significantly deteriorated gas exchange indices, except for functional shunt, in COVID-19-related acute respiratory distress syndrome. The respiratory system mechanics were not altered by the FiO 2 strategy. Clinical Trials Register: NCT04486729.
【저자키워드】 COVID-19, Respiratory distress syndrome, artificial, Respiration, Oxygenation, Respiratory mechanics, Pulmonary gas exchange, 【초록키워드】 protocol, clinical, Gas exchange, Patient, target, Respiratory system, respiratory, patients, acute respiratory distress, Invasive mechanical ventilation, Shunt, syndrome, fraction, Randomly, enrolled, selected, affected, significantly, applied, functional, not affected, was reduced, consecutive patient, diagnosis of COVID-19, liberal, moderate-severe, PaO, patients with moderate, 【제목키워드】 Impact, Gas exchange, target, acute respiratory distress, physiological, liberal,