Hemodynamic and Metabolic Effects of Ringers Lactate Solution in Hemorrhagic Shock

Abstract

Hemorrhagic shock in dogs was treated prior to irreversibility by Ringer''s lactate solution alone, Ringer''s lactate solution plus 1/2 the shed blood, or blood alone. Measurements included cardiac output, O2 comsumption, blood gas tensions and contents, pH, hematocrit and lactate, pyruvate, and excess lactate levels. The total body metabolic deficit was adequately corrected by all 3 treatment programs. However, when Ringer''s lactate solution was used alone normal O2 consumption was maintained only by increased cardiac output and increased O2 extraction with a low venous O2 content. Ringer''s lactate solution given with blood decreased the volume of blood required to provide adequate cardiac output, Oo consumption and blood gas contents. Ringer''s lactate solution, in the volumes and rate, given, transiently increased cardiac output beyond the control value, whereas blood did not. The buffered saline provided some immediate correction of metabolic acidosis, but 3 hr. after treatment there were no significant differences in any of these measured parameters in the 3 groups. Animals given Ringer''s lactate solution plus 1/2 the shed blood had a normal hemotocrit at the end of the study. Previously described beneficial effects of electrolyte solutions in addition to blood as compared to blood alone in the treatment of hemorrhagic shock seem to be due in part to better flow characteristics of blood with hemodilution.