Effects of fluid resuscitation on MAP in the three groups. MAP in all patients was registered by professional statisticians in the hospitals. There were no differences in MAP among the three groups at all the six time points. Comparing MAP in the same group, MAP at T60, T90, T120 and T8h was significantly higher than that at T0 in the Ns group; the parameter at T90, T120 and T8h was higher than at T0 in the Hs group; and MAP at T30, T60, T90, T120 and T8h were higher than that at T0 in the Sb group (*p < 0.05). MAP increased earlier in the Sb group than in the Ns and Hs groups.