Oxidative Effects of Isoflurane and Medetomidine - Tiletamine / Zolazepam Combination in Beagle Dogs

The present study evaluated the effects of different anesthesia techniques on oxidative stress in beagle dogs. Ten dogs were randomly assigned to either total intramuscular anesthesia with medetomidine-tiletamine/zolazepam (MTZ) combination (group T, 40 ㎍/㎏ medetomidine and 2 ㎎/㎏ tiletamine/zolazepam) or volatile anesthesia with isoflurane (group I, 2% isoflurane and 100% oxygen). Heart rate, respiratory rate, and rectal temperature for vital signs and the concentration of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) for oxidative stress were measured. SOD activity decreased significantly from baseline anesthesia in both groups (p ＜ 0.05). CAT and GPx activities were also decreased significantly after anesthesia between both groups (p ＜ 0.05). CAT activity decreased significantly from baseline after anesthesia in both groups, but activities of group I were significantly higher compared with group T after anesthesia (p ＜ 0.05). GPx activity in group T decreased significantly from baseline after anesthesia, but activities of group I were significantly higher compare with that of group T 1 hour after the conclusion of anesthesia (p ＜ 0.05). In conclusion, general anesthesia seems to induce oxidative stress, and volatile anesthesia with isoflurane attenuates oxidative injuries in beagle dogs.