The distribution of urinary biomarkers in different groups by blood transfusion is shown in box plot. The bars represent the inter-quartile range and the solid lines in the bars represent the median values of first post-operative urinary IL-18 and urinary NGAL. The median values of both urinary IL-18 and urinary NGAL were significantly elevated in the group that received > 2 PRBC units compared to those who received < 2 (P values for Wilcoxon test <.0001 and <.0001 respectively) or no blood (P values for Wilcoxon test <.0001 and <.0001 respectively).
* No Blood vs. More than 2 PRBC p value <.0001,
^ Less than 2 PRBC vs. More than 2 PRBC p value <.0001.