The mean PrRPl/B was @ and @ ( @ % CI = @-@ @ and @-@ @ ) on the first postoperative day , and it remarkably dropped down to @ and @ ( @ % CI = @-@ @ and @-@ @ ) on the second day in Groups S and C , respectively , and remained below @ on the third day ( repeated-measures of ANOVA design , post hoc ` within-group ' comparison of the first postoperative day versus second and third days ; P < @ ) .