Fever is frequent after extracorporeal membrane oxygenation (ECMO) decannulation. We aimed to evaluate the incidence of post-decannulation fever and describe its causes.

Adult ECMO patients who were successfully weaned from ECMO were retrospectively included. Minimal and maximal core temperatures were collected daily for each patient from 48 h before decannulation up to 5 days after. Patients were grouped according to the cause of fever (infection, thrombosis, or no evident cause) and compared. Plasma cytokine profile was obtained, each day from decannulation to 5 days after for 20 patients.

Between January 2021 and December 2022, 123 patients successfully weaned from ECMO were included. Post-decannulation fever occurred in 54 patients (44 %). It was associated with an infection in 39 patients (72 %) and with a thrombosis in 6 patients (11 %), and no cause was identified in the remaining 9 (17 %). Prolonged ECMO duration, extended ICU length-of-stay, diabetes and vascular comorbidities were significantly associated with a higher risk of infection. Finally, the pro-inflammatory cytokine profiles did not differ between febrile and afebrile patients.

Post-decannulation fever was common, and was mainly due to infections or thrombosis. Fever should therefore not be considered as a benign inflammatory reaction until proven otherwise.