Lactated Ringer's solution alleviates brain trauma-precipitated lactic acidosis in hemorrhagic shock

To determine the influence of brain trauma on blood acid-base and lactate-pyruvate responses to hemorrhage, and the effect of lactated Ringer's solution on these responses, 30 anesthetized rats were assigned to four groups: hemorrhage (n = 7), hemorrhage following fluid percussion brain trauma (trauma-hemorrhage group) (n = 7), hemorrhage treated with lactated Ringer's solution (hemorrhage-resuscitation group) (n = 8), and hemorrhage following brain trauma treated with lactated Ringer's solution (trauma-hemorrhage-resuscitation group) (n = 8). The hemorrhage group showed no significant changes in pH, HCO3, and base excess after hemorrhage. Base excess and pH were significantly reduced after the hemorrhage in the trauma-hemorrhage group but were raised after resuscitation in the hemorrhage-resuscitation group. Acid-base values showed no difference between the trauma-hemorrhage-resuscitation and hemorrhage groups. The trauma-hemorrhage-resuscitation group also had a significantly higher base excess than the trauma-hemorrhage group. Lactate rose significantly after hemorrhage in the hemorrhage group and was even higher in the trauma-hemorrhage group, but there were no differences between the hemorrhage versus hemorrhage-resuscitation or trauma-hemorrhage-resuscitation groups. Both brain trauma and lactated Ringer's solution increased pyruvate with marked reduction in the ratio of lactate to pyruvate. These data indicate that brain trauma precipitates blood lactate accumulation and metabolic acidosis after hemorrhage, and infusion of lactated Ringer's solution can relieve these disturbances.