The Risk Factors Investigation For Postoperative Delirium After Thoracic Surgery In Middle-Aged And Elderly Patients

OBJECTS:Postoperative delirium is a common abnormal mental state with sudden appearance and obvious fluctuation,characterized by different degrees of cognitive impairment,loss of sense of direction and confusion.The incidence of postoperative delirium in elderly patients is 5%-50%,and even as high as 87%in intensive care patients,but often missed.Postoperative delirium not only increases the incidence of other postoperative complications,prolongs the length of hospital stay,and increases medical expenses,but also leads to loss of self-care ability and cognitive decline of patients,which ultimately leads to increased perioperative mortality.At present,prevention is considered to be the most effective way to reduce postoperative delirium.Therefore,it is of great significance to understand the risk factors of postoperative delirium and give active intervention to reduce the occurrence of postoperative delirium.METHODS:Since from June 1st,2018 to December 31st,in all of the patients from a surgery medical team in the Department of Cardiothoracic Surgery of the First Affiliated Hospital of Chongqing Medical University,136 patients above 50 years old were selected,which suffered from thoracic surgery.The following eight aspects,including patients' diagnosis,basic information(gender,age,height,weight),personal history(smoking history,drinking history,basic diseases,which includes hypertension,diabetes,coronary heart disease,COPD,etc.),preoperative psychological state(whether to have a sleep disorder,cognitive impairment,mental illness,etc.),preoperative examination results(lung function,echocardiography,chest CT,blood routine,renal function,arterial blood gas analysis,etc.),anesthesia evaluation(ASA grade,NYHA Class),intraoperative situation(anesthesia time,operation time,blood loss,the dosage of anesthetic drugs,muscle relaxants,intraoperative rehydration fluids,etc.)and postoperative situation(extubation time,blood transfusion,ICU hospitalization duration,postoperative hospitalization duration,etc.)were used for statistical analysis of this risk assessment,whose outcome variable was postoperative delirium.REUSLTS:Twenty-one patients occurred postoperative delirium,with an incidence of 15.44%.Compared with non-POD group,the POD group showed a significant difference(p<0.05)in age,weight,BMI,history of driiking alcohol,hypertension,COPD,whether preoperative pulmonary infection,oxygenation index,ASA grade,the nature of the lesion,surgical site,operation time,intraoperative propofol anesthesia duration,dosage,blood transfusion,ICU hospitalization duration,and postoperative hospitalization duration,etc.There was no significant difference(p>0.05)in history of smoking,diabetes mellitus,coronary heart disease,LVEF,FEV1,preoperative hemoiglobin level,blood glucose level,serum creatinine level,electrolyte level,blood,loss,type and dosage of muscle relaxant,and postoperative extabation duration.Doing Multivariate Logistic Regression Analysis indicated that age?70(p=0.035,OR 7,658,95%CI 1.151-50.937),BMI<18.5(p=0.030,OR 13.876,95%CI 1.240-155.224),history of hypertension(p=0.020,OR 7.272,95%CI 1.375-38.460),oxygenation index<300(p=0.021,OR 65.059,The 95%CI 1.877-2254,813)and the propofol dosage>500mg(p=0.043,OR 46.187,95%CI 1.125-1896.834)were directly related to the occurrence of postoperative delirium after thoracic surgery.CONCLUSIONS:Advanced age,low BMI,history of hypertension,low oxygenation index and increased propofol dosage were independent risk faetors for postoperative delirium in middle-aged and elderly patients over 50 years old.