Effects Of Dexmedetomidine On Sleep Quality And Cognitive Function In Middle-aged And Elderly Patients Undergoing Orthopaedic Surgery

Objective:Postoperative cognitive dysfunction(POCD)(In 2018,six well-known journals,including BJA,suggested renaming postoperative cognitive dysfunction as perioperative neurocognitive dysfunction to describe preoperative and postoperative neurocognitive impairment.In order to accurately describe the scope of this study,the original name POCD is still used in this study)refers to the changes of personality,social and cognitive function after operation,with the decline of learning and memory as the main characteristics.The purpose of this study: 1.To clarify the effect of perioperative dexmedetomidine on sleep quality of middle-aged and elderly patients undergoing orthopaedic surgery.2.To investigate the effect of dexmedetomidine on cognitive function of middle-aged and elderly patients undergoing orthopaedic surgery during perioperative period.Methods: This study was approved by the Ethics Committee of Nanjing Drum Tower Hospital.87 patients aged 50-80 years old with ASAI-III grade who underwent orthopaedic surgery in Nanjing Drum Tower Hospital from April to July 2019 were selected.The subjects were divided into experimental group(group D)and saline control group(group C).Dexmedetomidine was continuously pumped 0.1?g/kg/h from the beginning of anesthesia in experimental group,while saline was used in control group.Anesthesia induction: midazolam 0.05mg/kg,etomidate 0.15-0.3mg/kg or propofol 1.5mg/kg,fentanyl 3-6?g/kg or sufentanil 4?g/kg,vecuronium 0.1mg/kg,Anesthesia maintenance: propofol 4-12mg/kg/h,remifentanil 0.2-0.5?g/kg/min,cis-atracurium 0.1 mg/kg/h,and adjust the speed of drug pump timely according to the operation process.PACU resuscitation was administered after operation.The Pittsburgh Sleep Scale(PSQI)and Sleep Number Scale(NRS)were tested on the day of admission(D0).The NRS scores of sleep on the first(D1),second(D2),third day(D3)and the seventh day(D4)after operation were recorded.On admission day(D0)and the seventh day after operation(D4),the cognitive function of patients was assessed by Repeatable Battery for the Assessment of Neuropsychological Status(RBANS).Telephone follow-up 1 month after operation.Cognitive and quality of life were assessed using the revised Cognitive Function Telephone Questionnaire(TICS-m)and Barthel Index.Results: 1.There were no significant differences in age,sex,BMI,preoperative Hb,MAP,HR,PSQI,NRS score,RBANS total score,preoperative basic diseases(hypertension,diabetes)between the two groups(P > 0.05),and the data of the two groups were comparable.2.There was significant difference in the NRS score of the patients in the control group on the first day after operation compared with the baseline sleep before operation(P < 0.05).3.The NRS scores of the first day after operation in the two groups were significantly different(P < 0.05).There was no significant difference in the NRS scores of the second day,the third day and the seventh day after operation(P > 0.05).4.There was no significant difference in the incidence of POCD between the two groups(P > 0.05).5.There was no significant difference in the incidence of adverse events(hypotension,bradycardia,nausea,vomiting and respiratory depression)between the two groups(P > 0.05).6.There was no significant difference in the revised TICS-m and Barthel index scores between the two groups one month after operation(P > 0.05).7.According to the occurrence of POCD,the patients were divided into POCD group and non-POCD group.The suspicious factors affecting the occurrence of POCD were analyzed by multivariate logistic regression.The results showed that diabetes mellitus might be a risk factor for POCD occurrence,P = 0.006,OR = 4.664,95% CI [1.540,14.122].Conclusion: Under this experimental condition: 1.The study suggests that the sleep quality of middle-aged and elderly patients with orthopaedic surgery on the first day after operation is lower than that before operation.2.Continuous perioperative infusion of 0.1 ?g/kg/h dexmedetomidine for 24 hours can improve the sleep quality of middle-aged and elderly patients undergoing orthopaedic surgery on the first day after operation,but it does not improve the sleep quality on the second,third and seventh day after surgery.3.Continuous perioperative infusion of 0.1?g/kg/h dexmedetomidine for 24 h did not significantly reduce the incidence of early postoperative cognitive dysfunction,and did not significantly improve the cognitive function and self-care ability of daily life for one month after surgery.4.Continuous perioperative infusion of 0.1?g/kg/h dexmedetomidine for 24 hours does not increase the risk of hypotension,bradycardia,nausea and vomiting,respiratory depression after operation,and is a relatively safe clinical dosage.5.Diabetes mellitus may be a risk factor for POCD.