The influence of sevoflurane or propofol on elderly patients' serum homocysteine and post-operative cognitive functions

Abstract

Objective The aim of this study is to observe the influence of sevoflurane or propofol anesthesia on postoperative cognitive functions of elderly patients and their serum homocysteine (Hcy).Methods Forty elderly patients,ASA Ⅰ-Ⅱ,undergoing gastrectomy surgery,were randomly divided into sevoflurane group (group A) and propofol group (group B).The venous blood sample was collected to test the homocysteine concentration by enzyme-linked immunosorbent assay (ELISA) at the begining of surgery(T1),2 h during the surgery(T2),24 h(T3) and 72 h after the surgery (T4).Meantime,the mini-mental state examination table (MMSE) was assessed.At 1 d before the surgery (S1),6 h (S2),24 h (S3) and 72 h after the surgery (S4).Results Compared with the preoperative values,the MMSE score of group B significantly decreased (P＜0.05) at S2,and the MMSE score of group A were lower than those of group B (P＜0.05).There was no significant difference between group in preoperative serum Hcy [group A:(5.8±1.4) μmol/L; group B:(5.9±1.6) μmol/L].Compared with the preoperative values,serum Hcy of group A (6.7±1.5) μmol/Lwere significantly higher at T2 (P＜0.05).However,serum Hcy decrease to the preoperative value level(P＞0.05) at T3 and T4.While in group B,the serum Hcy keep stable at T2,T3 and T4 (P＞0.05).Conclusions Both propofol and sevoflurane can cause shortterm postoperative cognitive functions in the elderly patients.Continuous inhalation of 1.3 MAC sevoflurane for 3.5 h has significant impact on postoperative cognitive dysfunctions than infusion of propofol at the rate of 3 μg·kg-1 ·h-1-5 μg·kg-1·h-1 for 3.5 h.One of its mechanisms may be associated with increased serum Hcy concentration. Key words: Sevoflurane; Propofol; Homocysteine; Postoperation cognitive dysfunction