The Correlation Of Carotid Plaque And Serum LP-PLA2 With Postoperative Delirium In Geriatric Patients Undergoing Hip Replacement

[Background and Objective]Postoperative delirium(POD)is one of the major complications that occurs frequently in elderly hip surgery patients,and presages adverse outcomes.LP-PLA2 is an enzyme produced by macrophages that appears to play a role in oxidation and inflammatory reactions,related with the development of carotid plaque and its rupture.The study was designed to identify the correlation of carotid plaque and serum LP-PLA2 with postoperative delirium in elderly patients.[Materials and methods]The study chose 62 elderly patients underwent spinal-epidural anesthesia combined with fascia iliaca nerve block for hip replacement at Qilu Hospital of Shandong University from July 2016 to Janurary2017.Recording these information of patients:age,gender,history(hypertension,diabetes,coronary heart disease,arterial fibrillation),electrocardiogram(ECG),whether taking statins,preoperative laboratory tests(neutrophil count,total cholesterol TC,triglyceride,low density lipoprotein cholesterol(LDL),high-density lipoprotein cholesterol(HDL),urea nitrogen,smoking,drinking history,family history,education degree.Carotid ultrasonography was performed before surgery to evaluate the existence of carotid plaque and the severity of carotid stenosis.POD was diagnosed by confusion assessment method(CAM).Perioperative(preoperative,postoperative,postoperative day 2)blood samples were collected for the determination of serum LP-PLA2 with enzyme linked immunosorbent assay(ELISA).According to the whether present carotid atherosclerotic plaques,patients were divided into plaque group and non-plaque group.According whether occur POD,plaque group were divided into POD subgroup and no-POD subgroup.[Results]Baseline demographics of two groups and preoperative laboratory data is statistically indifferent(P>0.05).There was no statistical difference in postoperative RASS Score and VAS between two groups(P>0.05).However,the incidence of POD is higher in plaque group than the control group(P<0.05).There was no statistically difference in the level of LP-PLA2 between plaque group and the control group at time of preoperative,postoperative or postoperative day 2(P>0.05).In plaque group,there is a significantly difference in the level of LP-PLA2 on day 2 after surgery between POD subgroup and no-POD subgroup(P<0.05),but not the time of preoperative and postoperative(P>0.05).[Conclusion]Carotid plaques have significant influence on the development of postoperative delirium.And patients suffering with POD have a higher level of LP-PLA2 than patients without POD on day 2 after surgery,which suggested that the instability of plaques is related with POD.