The effects of sevoflurane on recovery of brain energy metabolism after cerebral ischemia in the rat: a comparison with isoflurane and halothane.

UNLABELLED: Isoflurane is an appropriate anesthetic for neuroanesthesia. We evaluated whether the effect of sevoflurane is similar to that of isoflurane or halothane on brain energy metabolism after cerebral ischemia followed by reperfusion using 31P-magnetic resonance spectroscopy. Wistar rats (n = 21) were divided into three groups: isoflurane-, sevoflurane-, or halothane-treated. After anesthesia induction and surgical preparation, each anesthetic concentration was adjusted to 1 minimum alveolar anesthetic concentration. Cerebral ischemia was induced with bilateral carotid occlusion and reduction of mean arterial blood pressure to 30-40 mm Hg by blood withdrawal. Magnetic resonance measurements were performed during ischemia and for 120 min of reperfusion. Intracellular pH in the isoflurane-treated, sevoflurane-treated, and halothane-treated groups decreased to 6.180 +/- 0.149, 6.125 +/- 0.134, and 6.027 +/- 0.157, respectively, at the end of ischemia. There were no differences in the change of phosphorous compounds and intracellular pH between the isoflurane-treated and the sevoflurane-treated groups during ischemia and reperfusion. However, in the halothane-treated group, we observed a significant delay in the recovery of adenosine triphosphate and intracellular pH (0.038 +/- 0.013 pH unit/min compared with 0.064 +/- 0.011 in the isoflurane-treated group and 0.058 +/- 0.008 in the sevoflurane-treated group) until 24 min of reperfusion (P < 0.05). We conclude that sevoflurane has effects similar to isoflurane on brain energy metabolism during and after cerebral ischemia. IMPLICATIONS: It is important to know whether anesthetics adversely effect brain metabolism during ischemia and reperfusion. A new anesthetic, sevoflurane, affected the brain in a manner similar to isoflurane, which has been used for many years as an anesthetic.