Effects of ketamine and midazolam combination anesthesia on focal cerebral ischemia injury in rats

Objective: We investigated the effects of anesthesia with ketamine and midazolam on focal cerebral ischemia injury, and evaluated the neuroprotective properties of this combination during surgical procedures. Methods: Thirty male Sprague-Dawley rats were subjected to permanent middle cerebral artery occlusion (MCAO) under ketamine or ketamine-midazolam intraperitoneal anesthesia (n = 15 each). The neurological scoring was performed to determine functional impairment of the brain at 4 h after MCAO. TTC staining of brain slices was used to measure infarct size of the brain at 24 h after MCAO. At day 3 after MCAO, TUNEL staining was employed to detect apoptotic cells in the penumbra. Results: Although neurological scoring (1.57±0.65 vs 1. 74±0.52) was not significantly different between ketamine and ketamine-midazolam groups(P > 0. 05), infarct size and apoptotic cell density in the penumbra were significantly lower in the ketamine-midazolaml group than those in the ketaminel group (infarct size: (24. 1±4. 63)% vs (38.48±4.18)%; apoptotic cells density; (178±23) cells/mm₂ vs (258±15) cells/mm2, P<0. 0.5), respectively. Conclusion: The above findings suggested that ketamine and midazolam combination might provide neuroprotection during surgical procedures that pose risk for ischemic cerebral injury.