Emergency Interventions After Severe Traumatic Brain Injury in Rats: Effect on Neuropathology and Functional Outcome

摘要

Traumatic brain injury (TBI) contributes to combat morbidity/ mortality. Studies in models of TBI have focused on novel mediators and mechanisms. We used controlled cortical impact (CCI), a contemporary model of TBI in rats to study field-oriented treatments. The following technical objectives were addressed: (1) What is the optimal ventilation strategy. (2) Is hypothermia beneficial. and (3) What is the optimal sedative/analgesic. A fourth objective, combining hypothermia plus other therapies was abandoned due to the limited efficacy of hypothermia. The most important findings/publications include: Objective (1) In a report published in the Journal of Neurosurgery, we demonstrated that early aggressive hyperventilation worsened neuronal death. Objective (2) We published the first report showing that hypothermia was ineffective in the combat-relevant scenario of CCI followed by secondary hypoxemia. That work is in press in Critical Care Medicine. Objective (3) We reported remarkably poor outcome in rats treated with narcotics (fentanyl) versus general anesthesia (isoflurane) after CCI. That work was presented at the 1999 meeting of - the National Neurotrauma Society by research trainee Dr. Kimberly Statler, who received the Women in Neurotrauma Award. The paper is in press in the Journal of Neurotrauma. Since narcotics are the current field treatment after TBI, we then completed a seven anesthetic study in our CCI model. This is the first comprehensive assessment of the effect of anesthetic agents on outcome in experimental TBI. Notably, agents that are commonly used in the field (narcotics, benzodiazepines, and propofol) had detrimental effects on selective aspects of outcome. The results of this study will be presented at the National Neurotrauma Society meeting this fall.