Liver injury as a model of uncontrolled hemorrhagic shock: resuscitation with different hypertonic regimens

Using a standardized liver injury model of uncontrolled hemorrhage, we tested the effect of different hypertonic solutions on mortality, blood pressure, intra-abdominal bleeding, and circulating blood volume. After liver injury, rats were randomized to 4 groups: lactated Ringer's (LR, n = 10), Isosal (ISO, n = 10), hypertonic saline (HS, n = 10), and hypertonic sodium acetate (HA, n = 10). In all resuscitation groups, 4 mL/kg was infused at a rate of 0.4 mL/min. Blood volume was evaluated both directly and by estimation. Mortality was highest after HA resuscitation (40%) and lowest after HS resuscitation (0%), but this difference was not significant. Blood pressure was significantly higher after HS resuscitation, and this difference was sustained for 4 hours. The HA resuscitation did not increase blood pressure compared with LR resuscitation. Intraperitoneal blood volume was significantly higher with HS (25.5 +/- 0.7 mL/kg) and HA (26.8 +/- 1.2 mL/kg) than with LR (22.5 +/- 0.4 mL/kg). The HA resuscitation led to a significantly larger drop from baseline values of estimated terminal circulating blood volume than LR resuscitation. Nonparametric analysis combining survival time and directly measured change in blood volume demonstrated a significant advantage to HS, compared with LR. HA and HS resuscitations increased bleeding from uncontrolled solid viscus injury. The HS resuscitation restored blood pressure better than the other hypertonic solutions and maintained circulating blood volume in spite of increased bleeding. The HA and ISO resuscitations did not exhibit any advantage over LR in resuscitation of solid viscus injury.