Effects of resuscitation fluid on neurologic physiology after cerebral trauma and hemorrhage

Background: The current standard of care for fluid resuscitation of hemorrhagic hypotensive patients involves the use of crystalloid solutions. Traumatic brain injury (TBI) is often associated with hemorrhage and hypotension, which can contribute significantly to morbidity and mortality. Guidelines for the choice of fluid resuscitation and the use of red blood cell transfusions are not yet clear in the context of brain injury. Methods: Various fluid resuscitation strategies were evaluated in Sprague-Dawley rats using fresh blood, normal saline, hypertonic saline, and albumin fluid resuscitation protocols. Mean arterial blood pressure (MAP) and cerebral oximetry were assessed in hemorrhaged groups and the mean population spike amplitudes (PSA) from the hippocampus were examined in fluid percussion injured (FPI) animals subject to hemorrhage and fluid resuscitation. Results: MAP in control animals, hemorrhage and hemorrhage + albumin treated groups was 82.4 +/- 1.5 mm Hg, 55.7 +/- 1.5 mm Hg, and 97.0 +/- 3.4 mm Hg, respectively. Arterial PaO2 was higher in albumin-treated animals relative to other fluid alternatives. Regional tissue oxygen tension (PbrO2) levels in hemorrhaged animals reached significantly higher levels in albumin treated group compared with in normal saline and hypertonic saline (p < 0.001, p=0.034, respectively). After FPI+hemorrhage, PSA values in albuminresuscitated animals were significantly higher than in normal saline-resuscitated animals (p=0.012). Conclusions: The results of normal saline resuscitation, relative to other fluid alternatives, suggest that a re-evaluation of current treatment strategies in hemorrhagic hypotensive TBI patients is warranted. Albumin demonstrated the greatest beneficial effects on neurophysiology endpoints over crystalloid alternatives. These data suggests that albumin resuscitation may play an important role in the treatment of hemorrhagic hypotension and TBI.