The Effect Of Different Dose Of Lidocaine On Early Postoperative Cognitive Function In Elderly Patients Following Laparoscopic Gastric Cancer Surgery

Objective: To observe the effect of different dose of lidocaine on early postoperative cognitive function in elderly patients following laparoscopic gastric cancer surgery.Methods: Sixty elderly patients, aged 65 ~75 years, 18kg/m2<BMI<30kg/m2,of ASA ?~?grade scheduled for elective laparoscopic gastric cancer surgery were divided into three groups with 20 cases each: control group(group C),lidocaine 1 group(group L1), lidocaine 2 group(group L2). Five minutes before induction of anesthesia, group L1 received lidocaine as a bolus of 1mg/kg, followed by a continuous infusion at 1mg?kg-1?h-1 until the end of the surgery. Five minutes before induction of anesthesia, group L2 received lidocaine as a bolus of 2mg/kg, followed by a continuous infusion at 2mg?kg-1?h-1 until the end of the surgery. Group C, normal saline administered as a bolus and an infusion with the same volume and rate changes as the lidocaine group. There groups of patients with other anesthesia treatment are the same, BIS45~50. Before induction of anesthesia, the left radial artery and the right jugular vein puncture and catheterization after the local anesthesia. Blood samples were taken from internal jugular vein simultaneously before induction of anesthesia(T1), at the end of surgery(T2), 1 day after surgery(T3). Blood samples were centrifuged 10 min, and serum was collected and placed in-70 ? refrigerator to save. The density of serum NSE and S-100? protein was detected by enzyme-linked immunosorbent assay. Using the Mini-Mental State Evaluation Scale(MMSE) score was measured postoperative cognitive function and record the incidence of POCD at 1 day before surgery(d1), 1 day after surgery(d2).Results: 1) The general composition, age, weight, grade of ASA, education had no statistically significant among three groups, P > 0.05. 2) VAS score, bleeding amount, operation time, anesthesia time had no statistically significant among three groups, P > 0.05.3) Compared with the baseline values at T1, the density of serum NSE and S-100? protein increased significantly at T2~T3(P < 0.05), but was not statistically significant at T4(P > 0.05) in group C. Compared with the baseline values at T1, serum NSE and S-100? protein were not changed significantly at T2~T4 in group L1 and L2(P > 0.05). Compared with the group C, the density of serum NSE and S-100? protein decreased significantly at T2~T3(P < 0.05), but was not statistically significant at T4(P > 0.05)in group L1 and L2. 4) At 1 days after surgery, the incidence of POCD in group C was 20%(4/20)?group L1 was 15%(3/20)?group L2 was 15%(3/20). Compared with the group C, the incidence of POCD was not statistically significant among three groups. Compared with the baseline values at d1, MMSE scores had no statistically significant at d2 among three groups, P > 0.05.Conclusion: The two doses of lidocaine can reduce the density of serum NSE and S-100? protein and have a cerebral protection effect, but had no difference in elderly patients following laparoscopic gastric cancer surgery. Lidocaine had no effect on early postoperative cognitive function in elderly patients.