Effects of Different Anesthesia Methods on POCD of Elderly Patients after Hip Replacement Surgery and the Mechanism

Objective: To investigate the effects of different anesthesia methods on postoperative cognitive dysfunction( POCD) in elderly patients after hip replacement surgery and its preliminary mechanism. Methods: A total of 100 elderly patients undergoing hip replacement surgery were enrolled in this study and randomized into general anesthesia group and epidural anesthesia group. Mini-mental state examination( MMSE) was used to evaluate the patients' cognitive ability one day before surgery( T1),one day after surgery( T2),and five days after surgery( T3) respectively. The patients' venous blood samples were collected at T1,T2,and T3,and ELISA was used to determine the serum Aβ and Tau protein levels. According to the fact that whether there was a POCD at T2,the patients were divided into observation group and control group and the changes of serum Aβ and Tau protein levels between the two groups were compared. Results: In general anesthesia group,the MMSE score at T2 was significantly lower,and the incidence of POCD at T2 was significantly higher( P 0. 05) than those in epidural anesthesia group. The protein levels of serum Aβ and Tau at T2 in observation group were significantly higher compared with those in control group( P 0. 05). Conclusions: The incidence of POCD in general anesthesia patients is higher than that in patients accepted epidural anesthesia. The rising level of serum Aβ and Tau protein may be one of the mechanisms for POCD development.