Study On The Effect Of Dexmedetomidine On The Anesthesia Recovery Period And The Protective Mechanism Of Neurocognitive Function In Elderly Patients Undergoing Radical Resection Of Colorectal Cancer

Background Postoperative cognitive dysfunction（postoperative cognitive impairment,POCD）,preoperative examination of mental disorders is not found,but postoperative brain dysfunction and postoperative complications are common.Symptoms of anxiety,memory impairment,and even memory loss,restlessness,cognitive impairment,and language decline are the main symptoms,and even more are psychotic symptoms such as.Cognitive impairment can have a severe adverse effect on the prognosis and quality of life,and may even threaten the health of the patient.While the elderly patients due to their own reasons,due to anesthesia and stress lead to cognitive dysfunction is more obvious,more prone to postoperative anesthesia for elderly patients with colorectal cancer,more attention should be paid to a reasonable choice of drugs of narcotic drugs,try to choose small effects on the body,and the function of the brain of narcotic drugs.Dexmedetomidine（Dex）is a novel alpha 2 adrenergic receptor agonist that can protect nerve function to some extent.Objective To study the protective effect of Dex on the recovery period and neurocognitive function in patients undergoing radical resection for colorectal cancer.Methods 88 cases of elderly patients with colorectal cancer who underwent radical surgery in our hospital from January 2015 to June 2017 were randomly divided into study group and control group,43 cases in the study group and 45 cases in the control group.The study group used Dex for anesthesia 1μg/kg patients induced by about 10minutes before Dex in the study,10 minutes after the operation of terminal pump maintenance loading dose of 0.5μg/（kg·h）after the completion of.The control group received the same amount of saline infusion with the same infusion method.Two groups of anesthesia and total intravenous anesthesia,anesthesia,two groups of patients were treated with 0.04mg/kg midazolam,0.3mg/kg with benzene by acid atracurium,0.25mg/kg etomidate and hydrochloric acid treatment Yiqu drug 0.5mg/kg injection of Intubation was then performed by the senior anesthesiologist to ensure the success rate of intubation.Before skin incision,intraoperative 1 time/daily,fentanyl citrate injection was 2 times,1 times/d,fentanyl citrate injection of propofol,anesthesia with continuous infusion of atracurium,according to the index adjustment at any time for patient dose of propofol.Recording technician,the use of Dex after intubation,skin incision,skin suture,6 time points after extubation were recorded for T₀,T₁,T₂,T₃,T₄,T₅,and each time point to record the mean arterial blood pressure MAP and heart rate（HR）.At the 3 time points were recorded before and after surgery,postoperative 1 and 6 days:T_a,T_b,T_c,Blood cortisol and fasting blood glucose levels were measured at each time point.The operation time,intraoperative blood loss,recovery time,the amount of propofol and postoperative adverse reactions in the two groups were analyzed.A simple Intelligence Scale（MMSE）score was measured and its cognitive function was measured.Result Compare with control group,the level of MAP and HR were decrease at T₂^T₅ in study group（P<0.05）.The operation time,blood loss and recovery time of the two groups were not statistically significant（P>0.05）,but the content of propofol was significantly lower than that of the control group（P<0.05）.After the operation,the blood cortisol and fasting blood glucose of the two groups decreased to some extent.At T_a,there was no significant difference between the two groups in blood cortisol and fasting blood glucose levels（P>0.05）.When T_b-T_c was used,the blood cortisol and fasting glucose levels in the study group were significantly lower than those in the control group（P<0.05）.There was no significant difference between the two groups in preoperative MMSE score（P>0.05）,but the scores of the two groups decreased to some extent,but the difference was statistically significant（P<0.05）.The probability of cognitive impairment in the study group was significantly lower than that in the control group,and the cognitive dysfunction in the study group was significantly lower than that in the control group（P<0.05）.There was no significant difference in cough and restlessness between two groups（P>0.05）,but bradycardia,respiratory depression,nausea and vomiting in the study group were significantly lower than those in the control group（P<0.05）.The total incidence of adverse reactions was 6.98%in the study group and 26.67%in the control group.The total incidence of adverse reactions in the study group was significantly lower than that in the control group（P<0.05）.Conclusion The elderly patients with colorectal cancer radical resection,the use of Dex anesthesia,has certain protective effect on postoperative cognitive function,reduce the incidence of cognitive dysfunction,has little effect on hemodynamics,adverse reactions after surgery,the clinical results with bed and a good prognosis,which can be widely used in clinical.