Attenuation of ischemic brain edema by pentobarbital after carotid ligation in the gerbil

The efficacy of pentobarbital in the treatment of ischemic cerebral edema was evaluated in 160 gerbils. Animals underwent carotid ligation under ether or pentobarbital (50 mg/kg) anesthesia. The pentobarbital anesthetized group received an additional dose of 30 mg/kg 4 h after ligation. Animals were evaluated for neurologic deficit at 4 and 8 h post-ligation, then sacrificed. Water content of each hemisphere and swelling percentage were calculated from the wet and dry weights of the hemispheres. Swelling percentage in animals anesthetized with ether was 6.374 +/- 0.89 SE, whereas gerbils who underwent sham carotid ligation showed a negligible (0.491 +/- 0.15) swelling percentage (p less than 0.01). Pentobarbital animals had a swelling percentage of 3.359 +/- 0.68. This represents a significant edema reduction compared to ether-anesthetized animals (p less than 0.01). Neurologic deficit was decreased by 56.7% (17/60 vs 30/60) in pentobarbital animals compared with ether animals (p less than 0.025). Mortality at 8 hours was reduced by 75% (2/60 vs 8/60) in pentobarbital animals (p less than 0.05).