Study of initial fluid resuscitation volume following hemorrhagic shock in rats

Objective To observe the fluid requirement while mean arterial blood pressure(MAP)resuscitated to 100mm Hg with different fluids on hemorrhagic shock in rats.Methods SD rats were used to make hemorrhagic shock model by 20%,35% and 45% hemorrhage.The Lactated Ringer' s(LR),hydroxyethyl starch(HES),7.5%NaCl/6% Dextran40(HSD)and LR + HES were used as resuscitation fluid.The fluid requirement to resuscitate MAP to 100mm Hg was recorded.Meanwhile the left intraventricular systolic pressure(LVSP),the maximal change rate of left intraventricular pressure(±dp/dtmax)of hemorrhagic shock rat,the artery blood gas and the survival time were observed.Results For 20% hemorrhagic shock rats,MAP could auto- matically restored to 90-100mm Hg.The initial fluid amount to restore hemodynamics to the stable condition in 35% hemorrhage group was less than 45% hemorrhage group.Among all observed fluids,the initial requirement of HSD was least,HES was the next.HES and LR plus HES improved hemodynamic parameter better than other groups.Blood gases in each group had significant difference.Conclusion Initial volume of different fluids to resuscitate different degree of shock is different.Among the fluid ob- served in the present study,the initial volume of HSD is least,but resuscitation effects of HES and LR plus HES are better.