The usage of immunosuppressant agents and secondary infections in patients with COVID-19 in the intensive care unit: a retrospective study

Although COVID-19 infection is an immunosuppressant disease, many immunosuppressant agents, such as pulse methylprednisolone (PMP), dexamethasone (DXM), and tocilizumab (TCZ), were used during the pandemic. Secondary infections in patients with COVID-19 have been reported recently. This study investigated these agents' effects on secondary infections and outcomes in patients with COVID-19 in intensive care units (ICUs). This study was designed retrospectively, and all data were collected from the tertiary intensive care units of six hospitals between March 2020 and October 2021. All patients were divided into three groups: Group I [GI, PMP (-), DXM (-) and TCZ (-)], Group II [GII, PMP (+), DXM (+)], and Group III [GIII, PMP (+), DXM (+), TCZ (+)]. Demographic data, P_aO/FiO₂ ratio, laboratory parameters, culture results, and outcomes were recorded. To compare GI-GII and GI-GIII, propensity score matching (PSM) was used by matching 14 parameters. Four hundred twelve patients with COVID-19 in the ICU were included in the study. The number of patients with microorganisms ≥ 2 was 279 (67.7%). After PSM, in GII and GIII, the number of (+) tracheal cultures and (+) bloodstream cultures detected different microorganisms ≥ 2 during the ICU period, neuropathy, tracheotomized patients, duration of IMV, and length of ICU stay were significantly higher than GI. The mortality rate was similar in GI and GII, whereas it was significantly higher in GIII than in GI. The use of immunosuppressant agents in COVID-19 patients may lead to an increase in secondary infections. In addition, increased secondary infections may lead to prolonged ICU stay, prolonged IMV duration, and increased mortality.