The Effects Of Dexmedetomidine On Postoperative Cognitive Dysfunction(POCD) And Perioperative Inflammation In The Elderly Patients

Objective: To observe the influence of dexmedetomidine on postoperativecognitive dysfunction (POCD) and cytokines in the elderly patients undergoingradical operation of thyroid carcinoma． Besides，attempt to investigate itsrelated mechanism．Methods:60patients older than65years undergoing elective radicaloperation of thyroid carcinoma by total intravenous anesthesia. All patientswere randomly divided into dexmedetomidine (DEX) group (group D) andcontrol group (group C),30cases in each group. Before anesthesia, the patientsin dexmedetomidine received infusion of dexmedetomidine0.5ug/kg at first10min,followed by0.3ug/kg/h infusion until30min before the end of operation.The patients in control group received the same volume of normal salineinstead. Record the general situation of the two groups of patients, such as age,gender, weight, level of education and surgical time. Record the total anestheticdose of the two groups of patients infusion intraoperative. The Mini MentalState Examination (MMSE) was used to assess cognitive function1d beforeoperation and1,7d after operation. The incidence of POCD was recorded.Blood samples were taken before anesthesia induction, at the end of operationand24h after operation for determination of tumour necrosis factor-α(TNF-α).Results: Sixty patients completed the study. Compared with the group C,propofol and remifentanil total in the D group was significantly reduced (P<0.05). Group D1d and7d after operation MMSE score improvedsignificantly, difference was statistically significant (P <0.05). The POCDincidence of1and7d after operation:C group to26.7%,10.0%, D group was16.7%,6.7%, compared with group C, difference was not statisticallysignificant (P>0.05). At the end of the surgery the serum TNF-αconcentrationin group D was significantly lower than group C (P <0.05). The serum TNF-αconcentration after24h of operation returned to preoperative.Conclusion: Dexmedetomidine could improve postoperative cognitivefunction of thyroid cancer in elderly patients, but could not reduce theincidence of POCD, the mechanism on the postoperative inflammatory factorsreduce. The Dexmedetomidine can effectively reduce the amount of patientsundergoing anesthetic and postoperative inflammation factors.