THE EFFECTS OF SEVOFLURANE ON RECOVERY OF BRAIN ENERGY-METABOLISM AFTER CEREBRAL-ISCHEMIA IN THE RAT - A COMPARISON WITH ISOFLURANE AND HALOTHANE

Isoflurane is an appropriate anesthetic for neuroanesthesia. We evalua ted whether the effect of sevoflurane is similar to that of isoflurane or halothane on brain energy metabolism after cerebral ischemia follo wed by reperfusion using P-31-magnetic resonance spectroscopy. Wistar rats (n = 21) were divided into three groups: isoflurane-, sevoflurane -, or halothane-treated. After anesthesia induction;and surgical prepa ration, each anesthetic concentration was adjusted to 1 minimum alveol ar anesthetic concentration. Cerebral ischemia was induced with bilate ral 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. Intracellul ar pH in the isoflurane-treated, sevoflurane-treated, and halothane-tr eated 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 differe nces in the change of phosphorous compounds and intracellular pH betwe en the isoflurane-treated and the sevoflurane-treated groups during is chemia and reperfusion. However, in the halothane-treated group, we ob served a significant delay in the recovery of adenosine triphosphate a nd 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 se voflurane-treated group) until 24 min of reperfusion (P < 0.05). We co nclude that sevoflurane has effects similar to isoflurane on brain ene rgy metabolism during and after cerebral ischemia. Implications: It is important to know whether anesthetics adversely effect brain metaboli sm during ischemia and reperfusion. A new anesthetic, sevoflurane, aff ected the brain in a manner similar to isoflurane, which has been used for many years as an anesthetic.