IL6 and respiratory failure: Specifically, as indicated by standardized mean differences (SMD), patients in the CVP therapy group had a higher number of comorbidities, a higher modified sequential organ failure assessment (mSOFA) score, a lower paO2/FiO2 ratio, more severe acute respiratory failure grade (inspired by ARDS Berlin 2012-classification), and higher levels of adverse predicting laboratory parameters such as lactate, interleukin-6, and C-reactive protein.