Does the infusion rate of fluid affect rapidity of mean arterial pressure restoration during controlled hemorrhage

ObjectiveThis study aimed to compare 2 fluid infusion rates of lactated Ringer (LR) and hydroxyethyl starch (HES) 130/0.4 on hemodynamic restoration at the early phase of controlled hemorrhagic shock.MethodsFifty-six anesthetized and ventilated piglets were bled until mean arterial pressure (MAP) reached 40 mm Hg. Controlled hemorrhage was maintained for 30 minutes. After this period, 4 resuscitation groups were studied (n = 14 for each group): HES infused at 1 or 4 mL/kg per minute or LR1 infused at 1 or 4 mL/kg per minute until baseline MAP was restored. Hemodynamic assessment using PiCCO monitoring and biological data were collected.ResultsTime to restore baseline MAP ± 10% was significantly lower in LR4 group (11 ± 11 minutes) compared to LR1 group (41 ± 25 minutes) (P = .0004). Time to restore baseline MAP ± 10% was significantly lower in HES4 group (4 ± 3 minutes) compared to HES1 (11 ± 4 minutes) (P = .0003). Time to restore baseline MAP ± 10% was significantly lower with HES vs LR whatever the infusion rate.No statistically significant difference was observed in cardiac output, central venous saturation, extravascular lung water, and arterial lactate between 4 and 1 mL/kg per minute groups.ConclusionsIn this controlled hemorrhagic shock model, a faster infusion rate (4 vs 1 mL/kg per minute) significantly decreased the time for restoring baseline MAP, regardless of the type of infused fluid. The time for MAP restoration was significantly shorter for HES as compared to LR whatever the fluid infusion rate.