EARLY ISOTONIC SALINE RESUSCITATION FROM UNCONTROLLED HEMORRHAGE IN RATS

Background. Attempts to modify traditional fluid resuscitation have be en based on animal models that evaluate several variables including an esthesia. This study presents the effects of early saline resuscitatio n from severe uncontrolled hemorrhage in unanesthetized rats. Methods. Sixty-three female Sprague-Dawley mts were equally divided into three groups: group A, nonresuscitated; and groups B and C, resuscitated wi th isotonic saline (40 and 80 mL/kg respectively). Hemodynamics, blood loss, survival time, and mortality were recorded for 360 minutes afte r the hemorrhage, which was initiated by 75% resection of the tail. Re sults. In group C, 80 mL/kg of saline significantly lowered mortality (24% vs 76% and 71% for groups A and B, respectively) with concomitant increases in mean survival time (241 +/- 103 min vs 146 +/- 108 and 1 75 +/- 92 min for groups A and B, respectively). There were no statist ically significant differences in blood loss, hematocrit, or hemodynam ic parameters among the groups. Conclusions. Early and adequate isoton ic saline resuscitation of unanesthetized rats improved outcome despit e continuing hemorrhage. The significantly lower mortality rate and in creased survival fine were not a result of transiently improved arteri al pressure and did not correlate with blood loss. No significant blee ding increases were noted in the resuscitated groups.