Effect Of Different Concentration Sevoflurane Anesthesia On Postoperative Cognitive Function In Elderly Patients

BackgroundAlong with the aging society is increasing,for surgical treatment of elderly patients is increasing.Postoperative cognitive dysfunction(post operative cognitive dysfunction POCD)is a common complication in patients with central nervous system after operation,higher rate,especially after major surgery,among them the majority of elderly patients,this phenomenon is increasingly concerned by the anesthesia community.Foreign data show that postoperative cognitive dysfunction is often the result of multiple factors.Anesthetic drugs will have a certain impact on patient function of central nervous system after the surgery,now there have been some researches about the effect of sevoflurane inhalation anesthesia on postoperative cognitive function in elderly patients,Because of the evaluation criteria are often limited to an index,the result is lack of reliability.ObjectiveTo investigate the effects of different concentrations of sevoflurane anesthesia on postoperative cognitive function in elderly patients,and provide evidence for reducing postoperative cognitive dysfunction.MethodsEighty elderly patients who underwent cholecystectomy in our hospital were selected,the patients were randomly divided into A group of 1.0MAC(the lowest effective alveolar concentration)sevoflurane group;B group of 1.3MAC sevoflurane(control group);C group of 2.0MAC sevoflurane;the D group of 2.5MAC sevoflurane,20 cases in each group.Preoperative 24 h was performed on patients with MMSE score and recorded,the patient was detected by NBP,SPO2,ECG,BIS after them entered the room;The serum concentration of S100 beta protein was measured by venous blood sampling at 10 minbefore anesthesia.The patients were induced by intravenous anesthesia and induced into tracheal intubation,during the operation,the A groups inhaled 1.0MAC sevoflurane;inhalation of 1.3MAC sevoflurane in the B groups(control group);inhalation of 2.0MAC sevoflurane in group C;inhalation of 2.5MAC sevoflurane in group D,maintain BIS(bispectral index)value in 40-65,with intermittent intravenous sulfentanyl,cisatracurium and midazolam,observation of NBP,ECG,to observe NBP,ECG intravenous injection of vasoactive drugs when necessary,to maintain stable hemodynamics,10 min after operation and postoperative 24 h venous blood detection of S100 beta protein level and at the end of operation,6h,24 h,72h,7d and MMSE score of patients.The changes of S100 beta protein and MMSE score before and after the operation of anesthesia were observed,the data were statistically analyzed.ResultsThere were no significant difference in age,body weight,operation time and anesthesia time among the four groups(P>0.05).Preoperative MMSE score and the S100 beta protein levels also had no significant difference(P>0.05).The MMSE score in the group C were higher than those in the group B(P=0.056,P=0.015,P=0.000)at 6h/24h/72 h postoperation.There was no significant difference in MMSE score between the B group and C group(P=0.197)at 7day after operation.A group of patients with postoperative 6h MMSE score was lower than that of group B(P=0.035),S100 beta protein levels in the four groups of patients postoperative 10 min were significantly increased(A group 0.060 +0.016 ?g/L,B group 0.057+0.019 ?g/L,C group 0.058+0.027 ?g/L,D group 0.059+0.025?g/L),there was the difference compared with the preoperative(A group P=0.000,B group P=0.001,C group P=0.002,D group P=0.003);No significant difference between groups(P>0.05);S100 beta protein level after surgery in 24 h A group of 0.070 + 0.021 ?g/L compared with before surgery was significantly higher than the preoperative level,there was significant difference(P=0.000);after operation 24 h A group and the B group were significantly different(P=0.001).ConclusionPostoperative 24 h plasma S100 beta protein level of A group were higher than that of group B(control group);postoperative 6h MMSE score of A group was lower than that in group B(control group),postoperative 24 h and 72 hMMSE score of C group was higher than that of B group.The experiment suggests that the effects of sevoflurane anesthesia on postoperative cognitive function has negative correlation with inhalation concentration.