High Versus Low Volume Fluid Resuscitation Strategies in a Porcine Model (Sus Scrofa) of Combined Thermal and Traumatic Brain Injury.

Background Combined burn and traumatic brain injury (TBI) treatment priorities may not align due to opposing fluid resuscitation paradigms used in treating burns and TBI. We developed a porcine model of combined thermal injury/TBI and compared an "aggressive" fluid resuscitation strategy using the Parkland formula and a "restrictive" resuscitation strategy using the modified Brooke formula. Methods Twenty eight swine were deeply anesthetized and received a 40% total body surface area full thickness burn injury and TBI. Swine were then randomized to receive restrictive or aggressive resuscitation for eight hours after which time animals were euthanized and necropsy was performed. Volume of brain injury was assessed after analyzing segmental slices of brain tissue. Results There were no differences between the restrictive and aggressive resuscitation groups in blood pressure, heart rate, central venous pressure, intra-cranial pressure (ICP), or serum lactate levels after 8 hours of resuscitation. Urine output was higher in the aggressive resuscitation group. The restrictive group had a significantly higher serum BUN compared to baseline and compared to the aggressive group. There was no significant difference in size of brain injury between groups. Conclusions Both restrictive and aggressive resuscitation demonstrated adequate resuscitation at eight hours post-injury. Increased serum BUN in the restrictive group may be an indicator of early acute kidney injury, despite adequate urine output. Resuscitation strategy did not appear to affect ICP or the size of brain injury.