Fig. 3

Restricted cubic spline curve based on the multivariate Cox proportional hazards models. The multivariable-adjusted hazard ratios for 28-day mortality based on the dose of the initial vasopressor when additional vasopressors were administered are shown on a continuous scale. The solid red lines represent the multivariable-adjusted hazard ratios, and the pink filling represents the 95% confidence intervals derived from restricted cubic spline regressions with three knots. The dashed black lines show a hazard ratio of 1.0, indicating no association. The dashed red curves highlight the range of 0.25 μg/kg/min, which is suggested by the Surviving Sepsis Campaign for the administration of additional vasopressors