Fever and Leukocytosis Are Poor Predictors of Bacterial Coinfection in Patients With COVID-19 and Influenza Who Are Receiving Extracorporeal Membrane Oxygenation

Open Forum Infect Dis. 2023 Oct 9;10(11):ofad501. doi: 10.1093/ofid/ofad501. eCollection 2023 Nov.

Abstract

Background: Fever and leukocytosis are 2 parameters commonly cited in clinical practice as indications to perform an infectious workup in patients receiving extracorporeal membrane oxygenation (ECMO), but their utility is unknown.

Methods: All patients who received ECMO between December 2014 and December 2020 with influenza or COVID-19 were included in this retrospective cohort study. Cultures were included if they were drawn from patients without signs of decompensation. Maximum temperature and white blood cell count were recorded on the day of culture collection. Workups with infections were compared with those that were negative.

Results: Of the 137 infectious workups in this 45-patient cohort, 86 (63%) were performed in patients with no signs of decompensation, totaling 165 cultures. These workups yielded 10 (12%) true infections. There were no differences in median (IQR) temperature (100.4 °F [100.2-100.8] vs 100.4 °F [99.3-100.9], P = .90) or white blood cell count (18.6 cells/mL [16.8-20.1] vs 16.7 cells/mL [12.8-22.3], P = .90) between those with and without infections.

Conclusions: In patients with influenza or COVID-19 who require ECMO, fever and leukocytosis were common indications for infectious workups, yet results were frequently negative. Despite their use in clinical practice, fever and leukocytosis are not reliable indicators of infection in patients who are hemodynamically stable and receiving ECMO.

Keywords: diagnostic stewardship; extracorporeal membrane oxygenation; fever; infection; leukocytosis.