*2.4. COVID-19 Management*

The decision to hospitalize LTRs and the level of care needed were made by the lung transplant team based on disease severity. In general, LTRs were hospitalized if they had hypoxia or severe symptoms (tachypnea with a respiratory rate of >30 breaths/minute, chest pain, dyspnea, etc.) suggestive of a progression to respiratory failure and clinical instability. The standard of care of hospitalized COVID-19-infected LTRs was based on the disease stage and severity, using institutional protocols that were consistent with NIH treatment guidelines [17]. Patients with mild or moderate disease and unchanged baseline oxygenation were treated as outpatients. The general recommendation was symptomatic treatment, to isolate, hydrate well, and communicate with the LT coordinators if symptoms worsened. Immunosuppression management changed over the course of the pandemic, with a discontinuation of the cycle-cell inhibitors in all LTRs with any severity of COVID-19 during the Delta variant period, and in hospitalized LTRs regardless of the circulating variant at the time of a COVID-19 diagnosis. In patients with mild and moderate COVID-19 that were not hospitalized, a virtual visit was conducted 1 week after the diagnosis of COVID-19 to confirm clinical improvement or the need of hospitalization in case of disease progression. At follow-up visits, the decision to resume the cell-cycle inhibitor was made on average 31 days after discontinuation in 9 patients who did not require hospitalization. Additional therapy with monoclonal antibodies was utilized as they became available in outpatients to prevent disease progression.

For hospitalized patients with mild-to-moderate COVID-19, the administration of intravenous remdesivir was considered within 7 days of symptom onset. In patients with COVID-19-related pneumonia and hypoxia, the corticosteroid dose was increased. In addition, for patients in the ICU with high levels of inflammatory markers and oxygen therapy requiring non-invasive or invasive mechanical support, tocilizumab or baricitinib were considered on a case-by-case basis.
