Fig. 4

Time course of hourly fractional excretion of sodium before and after intravenous furosemide administration in the overall study population (single-dose group, group n = 39), as divided according to the median value of central venous pressure at baseline (8; 6–11). Data are expressed as median value and interquartile ranges. Baseline denotes the time of furosemide administration. Two-way ANOVA for repeated measurements was performed (P < 0.001 for time effect; P < 0.001 for group effect; P = 0.03 for interaction; *P < 0.05 vs. baseline, time 0). Na ⁺ sodium, CVP central venous pressure