Fig. 2

Association of circulating plasma concentration of inflammatory biomarkers angiopoietin-2, interleukin-6, and interleukin-8, with respiratory drive in univariable and multivariable models. Adjusted model 1 includes the biomarker of interest and measures of lung mechanics (tidal volume scaled to predicted body weight, end-inspiratory transpulmonary pressure, end-expiratory transpulmonary pressure), chemoreceptor input (pH, PaCO₂, PaO₂) and sedation depth (Richmond agitation-sedation score [RASS]). Adjusted model 2 includes all covariates in adjusted model 1 plus clinical markers of inflammation (maximum temperature and white blood cell count in the 24 h preceding enrollment) and an index of multiorgan dysfunction (sequential organ failure assessment [SOFA]). The biomarker of interest was entered as a continuous log-transformed variable into each model. Additional sensitivity analyses with alternative model formulations are reported in the online supplement