Changes in cerebral glucose metabolism induced by postoperative delirium in elderly patients and the effects of dexmedetomidine on it / 中华麻醉学杂志

ABSTRACT

Objective To investigate the changes in cerebral glucose metabolism induced by postoperative delirium in the elderly patients and the effects of dexmedetomidine on it.Methods Forty-two patients of both sexes aged 65-85 yr with a body mass index of 19-25 kg/m2 undergoing abdominal surgery under general anesthesia were enrolled in this study.Delirium occurred during the first 2 days after operation in 39 out of the 42 patients (29/42).The 29 patients were randomly divided into 2 groupsgroup delirium without any treatment (group D,n =13) and group delirium + dexmedetomidine (group Dex,n =16).The remaining 13 patients did not develop delirium after operation and served as control group (group C).In group Dex a loading dose of dexmedetomidine 1 μg/kg was administered iv over 10 min after occurrence of delirium followed by continuous infusion at 0.2-0.7μg· kg-1 · h-1.PET scan was performed within the time period in which delirium occurred.18 Fluorine-deoxyglucose was injected for observation of imaging of glucose metabolism.The standard uptake value of glucose of bilateral parietal,temporal and frontal lobes was calculated.Results Delirium was controlled within 30 min after adminnistration of dexmedetomidine.Delirium significantly reduced cerebral glucose metabolism in the bilateral parietal,temporal and frontal lobes in group D as compared with group C (P ＜ 0.05).Dexmedetomidine significantly attenuated the delirium-induced decrease in cerebral glucose metabolic rate of the 3 lobes in group Dex as compared with group D (P ＜ 0.05).Conclusion Postoperative delirium reduces cerebral glucose metabolism and dexmedetomidine can significantly control pastoperative delirium in the elderly patients.