Concentration of complement product C5a measured at inlet (C
), outlet (C
), in the ultrafiltrate (C
) and total mass production rate (M
) over time (median and interquartile range). Results of generalized estimating equations (symbols: ● no anticoagulation ■ heparin ▲ citrate) for C5a in A. Ci: highest in the citrate group (P = 0.016). B. Co: highest in the citrate group (P = 0.026), decreases over time (P = 0.012) but least in the citrate group (P = 0.008). C. Cuf: lowest in the citrate group (P < 0.001), decreases over time (P < 0.001). D. Mtp: decreases over time (P < 0.001), most in the heparin group (P = 0.007 for interaction).