A comparison of lactated ringer's solution to hydroxyethyl starch 6% in a model of severe hemorrhagic shock and continuous bleeding in dogs

In this randomized, controlled study in dogs, we examined the short-term effects of blood pressure targeted fluid resuscitation with colloids or crystalloids solutions on systemic oxygen delivery, and lactate blood concentration. Fluid resuscitation using hydroxyethyl starch (HES) 6% to a mean arterial blood pressure (MAP) of 60 mm Hg was compared with lactated Ringer's solution (LR) to a MAP of 60 or 80 mm Hg (LR60 and LR80, respectively). The model was one of withdrawal of blood to a MAP of 40 mm Hg through an arterial catheter that was then connected to a system allowing bleeding to occur throughout the study whenever MAP exceeded 40 mm Hg. Target MAP was maintained for 60 min with a continuous infusion of the designated fluid replacement. All 15 dogs (5 in each group) survived until the last measurement. Blood loss in the LR80 group (2980 ± 503 mL) (all values mean ± SD) was larger than in the LR60 and HES60 groups (1800 ± 389 mL, and 1820 ± 219 mL, respectively) (P < 0.001). Whereas 840 ± 219 mL of HES60 was needed to maintain target MAP, 1880 ± 425 mL of LR was needed in the LR60 group, and 4590 ± 930 mL in the LR80 group (P < 0.001). Lactate blood concentrations were smaller and delivered 02 higher in the HES60 group (35 ± 17 mg/dL and 239 ± 61 mL/min, respectively) in comparison to the LR60 group (89 ± 18 mg/dL and 140 ± 48 mL/min, respectively) and the LR80 group (75 ± 23 mg/dL and 153 ± 17 mL/min, respectively) (P = 0.02 and P = 0.026). In conclusion, fluid resuscitation during uncontrolled bleeding, to a target MAP of 60 mm Hg, using HES60 resulted in larger oxygen delivery and smaller systemic lactate A resuscitation to a target MAP of 60 or 80 mm Hg using LR.