Effect Of Lidocaine Versus Dexmetomidine On Postoperative Cognitive Function In Elderly Patients Undergoing Laparoscopic Surgery

Objective: To observe the possible effects of perioperative continuous infusion of dexmetomidine and lidocaine on the cognitive function of patients undergoing laparoscopic radical resection of rectal cancer under general anesthesia combined with epidural anesthesia.Methods: Ninety patients aged 65-75 years with ASA grade Ⅰ-Ⅲ undergoing laparoscopic radical resection of rectal cancer were randomly divided into three groups(nude 30): C group(control group),D group(dexmetomidine group)and L group(lidocaine group).Ten minutes before the induction of general anesthesia,the patients were intravenously injected with loading doses of normal saline,dexmetomidine and lidocaine,After that,continuous infusion was given until about 30 minutes before the end of the operation.The infusion of drugs to maintain general anesthesia was stopped at the end of suture parietal peritoneum.The central venous blood was collected before anesthesia(T1),at the end of the operation(T2)and 24 hours after the operation(T3).After the corresponding centrifugation,the serum was stored in the refrigerator at-80 ℃.Wait for later detection.Results: In the serum of the three groups,the level of S-100β protein and neuron specific enolase(NSE)increased significantly at T2 and T3,and the difference was statistically significant.Compared with group C,the levels of serum NSE and Smur100 β in group D and group L decreased significantly at T2 and T3,and the difference was statistically significant.Compared with group D,the levels of NSE and S-100β in serum of group L did not decrease significantly at T2 and T3,and the difference was not statistically significant(P > 0.05).MMSE scores were performed before operation and 1 day,3 days and 5 days after operation.The final results showed that the MMSE score of group C was lower than that of group L and group D on the 3rd and 5th day after operation.As for the awakening time and extubation time,the awakening time and extubation time in group D were longer than those in group C,and the difference was statistically significant(P < 0.05).However,there was no very significant effect in group L,and the difference was not statistically significant(P >0.05).Conclusion:Compared with dexmetomidine,perioperative infusion of lidocaine not only had no significant effect on awakening time and extubation time,but also reduced NSE concentration and serum S-100β protein in patients undergoing laparoscopic radical resection of rectal cancer,which could improve MMSE score and reduce the risk of POCD in the early stage after operation.It is of great significance to prevent the occurrence of POCD.