Oseltamivir for severe viral pneumonia in adult ICU patients

Abstract

Background: Patients with influenza pneumonia requiring intensive care unit (ICU) admission remain an important source of mortality. Early treatment of critically ill patients with oseltamivir has been associated with a survival benefit in observational studies. However, recommendations regarding oseltamivir therapy are controversial. The aim of this study was to assess the impact of early versus late oseltamivir therapy in ICU patients with severe viral pneumonia. Methods: This was a retrospective, observational study, which included adult patients admitted to our hospital's ICU with the diagnosis of influenza pneumonia confirmed by polymerase chain reaction (PCR) from January 1, 2016 to December 31, 2018. The patients were divided according to the timing of first oseltamivir administration into early or late oseltimivir groups (within or beyond 48h after the first contact with a healthcare provider after the onset of symptoms, respectively). All-cause mortality, length of ICU stay, duration of invasive mechanical ventilation (IMV) and occurence of bacterial superinfection were compared between the two groups. Results: The study population included 43 patients. A total of 27 (62.8%) patients took early oseltamivir compared to 16 (37.2%) patients who took late oseltamivir. Length of ICU stay, duration of IMV and incidence of bacterial superinfection were similar in both groups (P=0.251; P=0.324; and P=0.596, respectively). In the early oseltamivir group, a total of 5 deaths were registered at ICU, 28 days and 6 months after admission (18.5%), whereas in the late oseltamivir group the registered mortality was 7 (43.8%; HR=3.4 with 95% CI 0.8-13.7; P=0.075), 8 (50.0%; HR=4.4 with 95% CI 1.1-17.5; P=0.030) and 10 (62.5%; HR=7.3 with 95% CI 1.8-29.8; P=0.003) in the same periods. Conclusions: Mortality in the late oseltamivir group was significantly higher at 28 days and 6 months after admission, although it was similar between the two groups during ICU stay. More studies comprising a larger number of critically ill influenza patients may be required to further enlighten the debated benefits of early oseltamivir treatment in this specific group of patients.