Convalescent plasma therapy for COVID-19 in patients with nasal catheter oxygen therapy

Numerous studies have demonstrated that convalescent plasma therapy reduces mortality in coronavirus disease 2019 (COVID-19) patients. Current guidelines recommend nasal catheter oxygen therapy for most hypoxic patients during the early stages of the illness. However, limited data are available regarding the efficacy of convalescent plasma therapy in patients already receiving oxygen therapy. Given the widespread use of nasal catheter oxygen therapy in hypoxic COVID-19 patients and the increasing evidence supporting the efficacy of convalescent plasma, this study aimed to evaluate the efficacy and safety of convalescent plasma therapy in COVID-19 patients who were receiving early oxygen therapy.

A retrospective study was conducted at the First Affiliated Hospital of Ningbo University, analyzing 112 COVID-19 patients treated with convalescent plasma from December 2022 to July 2023. Data on demographics, laboratory tests, and plasma doses were collected before and after convalescent plasma transfusion, alongside standard care. The primary outcome was 28-day mortality, with laboratory parameters as secondary outcomes.

On day 28, the mortality rate was 20% in the convalescent plasma group compared to 44% in the standard-care group (P=0.008). In severe COVID-19 cases, mortality was 34% in the convalescent plasma group versus 59% in the standard-care group (P=0.04). Among patients who received nasal catheter oxygen therapy for 48 hours or longer, mortality was 21% in the convalescent plasma group compared to 42% in the standard-care group (P=0.02).

Convalescent plasma therapy administered to COVID-19 patients receiving nasal catheter oxygen therapy significantly reduced mortality at day 28.