Does early infusion of red blood cells after trauma and hemorrhage improveorgan functions?

Objective: Early management of trauma victims includes control of bleeding and rapid restoration of intravascular volume. However, it remains controve rsial whether infusion of blood products is superior to crystalloids alone. Therefore, it was the aim of the present study to determine whether resusc itation with red blood cells plus lactated Ringer's solution (RL) is more e ffective than RL alone in improving the cardiovascular and hepatocellular f unctions after trauma and severe hemorrhage. Design: Prospective study. Setting: Laboratory. Subjects: Sprague-Dawley rats. Interventions and Measurements: Male adult rats were anesthetized and under went a laparotomy to induce tissue trauma before hemorrhage. The animals we re then bled to and maintained at a mean arterial pressure of 40 mm Hg unti l 40% of the maximal bleed-out (MB) volume was returned in the form of RL, and were then resuscitated with either four times the volume of MB with RL or washed red blood cells (RBC) (similar to 45% the volume of MB) in three times the volume of RL over 60 mins. Various in vivo heart performance vari ables, cardiac output, and hepatocellular function (ie, the maximum velocit y and the overall efficiency of indocyanine green clearance) were determine d at 4 hrs after resuscitation. Hemoglobin, systemic oxygen delivery, circu lating blood volume, and plasma levels of interleukin-6 were also measured. Main Results: At 4 hrs after RL resuscitation, heart performance, cardiac o utput and hepatocellular function were significantly de pressed and plasma levels of interleukin-6 were significantly increased. Although infusion of RBC significantly increased mean arterial pressure, hemoglobin and oxygen d elivery compared with animals resuscitated with RL only, infusion of RBC di d not further improve the depressed cardiovascular and hepatocellular funct ions under such conditions. Conclusion: Because infusion of RBC and RL resuscitation do not improve org an functions compared with RL resuscitation without RBC, it appears that ph armacologic agents in addition to fluid resuscitation are needed to restore cardiovascular and hepatocellular functions after trauma and hemorrhage.