BackgroundAcute respiratory distress syndrome (ARDS) is a major complication in patients with severe coronavirus disease in 2019 (COVID-19). COVID-19 convalescent plasma (CCP) has been proposed as a specific therapy for patients with COVID-19. Our goal is to assess changes in oxygenation and inflammatory markers in patients after receiving CCP.MethodsThis is a retrospective, health system-based, a case-control study comparing hospitalized patients with COVID-19 who received CCP and were discharged (survivors) to patients who died after receiving CCP (non-survivors). We analyzed the severity of ARDS, oxygenation, and inflammatory markers of 295 patients, comparing 202 survivors to 93 non-survivors with COVID-19 who received CCP. Demographic information and laboratory data were collected on the day of the admission (initial), the day of the plasma infusion (D1), and post-infusion days 3, 7, 15, and 30 (when available).ResultsSurvivors were younger (52.48 y versus 64.02 y; p<0.001) with no pre-existing conditions (25.2% versus 13.9%; p=0.03) compared to non-survivors. Severe ARDS (PaO2/FiO2 <100) was predictive of increased mortality after CCP in non-survivors (p<0.001). Survivors with mild (20%) or moderate (46%) ARDS on D1 had a 54% resolution of ARDS on D7 after CCP (p<0.001). After 72 hours of transfusion, supplemental oxygen requirements decreased by 63% of the survivors, compared to 33% of non-survivors (p<0.001). Inflammatory markers, including white blood cells, absolute neutrophils, platelets, C-reactive protein (CRP), lactate dehydrogenase (LDH), and creatinine, improved within three days in survivors after CCP (p<0.05). Baseline findings associated with a poor prognosis on D1 include a lower platelet count (219.02 versus 281.64, p<0.001), higher blood urea nitrogen (BUN) (35.41 versus 21.48, p<0.001), higher creatinine (2.24 versus 1.26, p<0.001), higher D-dimer (5.88 versus 2.46, p<0.001) and elevated lactate dehydrogenase (LDH) (698.3 versus 464.51, p<0.001) when comparing non-survivors to survivors, respectively. After 72 hours post-transfusion, the following changes were remarkable: normalization of creatinine with a mean of 1.07 in survivors versus 1.92 in non-survivors (p<0.001), a significant decrease in CRP improving from 129.27 to 84.25 in survivors versus 139.11 to 130.0 in non-survivors (p<0.001), and lower lactate dehydrogenase (LDH) in survivors (459.47) versus non-survivors (674.56, p<0.001).ConclusionIn this retrospective, health system-based, case-control study, we found that the improvement in oxygenation, resolution of ARDS, and reduced inflammatory markers are seen in survivor patients after early COVID-19 convalescent plasma transfusion. These parameters can be used to assess response to COVID-19 convalescent plasma after 72 hours of the transfusion and could help physicians in the decision-making when administering CCP, especially if resources are scarce. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.