Controlled resuscitation for uncontrolled hemorrhagic shock

Objective: To test the hypothesis that controlled resuscitation can lead to improved survival in otherwise fatal uncontrolled hemorrhage. Methods: Uncontrolled hemorrhage was induced in 86 rats with a 25-gauge needle puncture to the infrarenal aorta. Resuscitation 5 minutes after injury was continued for 2 hours with lactated Ringer's solution (LR), 7.3% hypertonic saline in 6% hetastarch (HH), or no fluid (NF). Fluids infused at 2 mL · kg^-1 · min^-1 were turned on or off to maintain a mean arterial pressure (MAP) of 40, 80, or 100 mm Hg in six groups: NF, LR 40, LR 80, LR 100, HH 40, and HH 80. Blood loss was measured before and after 1 hour of resuscitation. Results: Survival was improved with fluids. Preresuscitation blood loss was similar in all groups. NF rats did not survive 4 hours. After 72 hours, LR 80 rats (80%) and HH 40 rats (67%) showed improved survival over NF rats (0%) (p < 0.05). Rebleeding increased with MAP. Attempts to restore normal MAP (LR 100) led to increased blood loss and mortality. Conclusion: Controlled resuscitation leads to increased survival compared with no fluids or standard resuscitation. Fluid type affects results. Controlled fluid use should be considered when surgical care is not readily available.