Improved survival time with combined early blood transfusion and fluid administration in uncontrolled hemorrhagic shock in rats.

OBJECTIVE

To test whether early blood administration combined with crystalloid solution infusion may prolong survival in a clinically relevant model of ongoing uncontrolled life-threatening hemorrhage.

METHODS

Light anesthesia was induced with halothane in 24 rats, and spontaneous breathing was maintained. Uncontrolled hemorrhagic shock was induced by withdrawal of blood at 2.5 mL/100 g over a 15-minute period, followed by 75% tail amputation. At 10 minutes after tail cutting, rats were randomized into four groups (n = 6 each): group 1, receiving 3 mL of shed blood for 5 minutes followed by 9 mL of lactated Ringer's (LR) solution for 15 minutes; group 2, receiving 9 mL of LR solution for 15 minutes followed by 3 mL of shed blood for 5 minutes; group 3, receiving 9 mL of LR solution only for 15 minutes; group 4, receiving neither of shed blood nor LR solution. Rats were then observed until death or a maximum of 180 minutes.

RESULT: Mean survival time was 138 +/- 30 minutes, 108 +/- 22 minutes, 79 +/- 13 minutes, and 55 +/- 18 minutes for groups 1, 2, 3, and 4, respectively (p < 0.05 among the four groups). Additional blood loss from the tail stump did not differ significantly between the three treatment groups.

CONCLUSIONS

In a model of uncontrolled hemorrhagic shock in rats, a resuscitation regimen using crystalloids agent alone is not ideal, and even a brief delay in blood administration worsens survival. Early blood administration combined with crystalloid solution infusion seems ideal.