Change Of Vascular Endothelial Growth Factor Level In Patients With Early Postoperative Cognitive Decline

Objective Postoperative cognitive dysfunction(POCD)as a kind of common postoperative complications,it more likely happens in elderly patients than younger patients.POCD is a decline in cognitive function,especially in memory,attention,executive functions and so on.These dysfunctions deeply affect daily life of patients after surgery.Up to date,the exact pathogenesis and diagnosis standard of POCD are undefined,a various of factors including operation types and anesthesia method are supposed to participate in the progress of it,so it is vital to prevent POCD early.Vascular endothelial growth factor(VEGF)is an important growth factor which is also called vascular permeability factor.Initially,it can induce endothelial cell proliferation and migration thus forming a new vascular net trough bonding to vascular endothelial growth factor receptor(VEGFR),so it was named vascular endothelial growth factor.In recent years,it was found to have neural nutrition and neural protection effects.The states of abnormal changes of hemodynamic ischemia and hypoxia can induce the increased expression of VEGF and promote the regeneration of blood vessels.Until now,we know little about early postoperative cognitive decline and variation of VEGF,so we hypothesized that early postoperative cognitive decline and the changes of vascular endothelial growth factor may have correlation.This study is to provide probable testing programs to detect early POCD through exploring the correlation between early postoperative cognitive decline and variations of VEGF.Methods First,the elderly patients(age≥65)undergoing orthopedics surgery with no cardiovascular disease and antidepressant disease history were selected.Mini-mental state examination(MMSE)was applied to evaluate the cognitive function of patients.Then they were divided into two groups accorded to their scores of MMS which were evaluated at 1 d before operation and 2 h after operation.There were two groups: experiment group(n = 20)and control group(n = 22)according to their scores of MMSE which was taken pre-operation and post-operation.Those whose scores of MMSE pre-operation higher 2 points than post-operative were divided to experiment control,whose scores post-operative higher 1 point or equal to pre-operative were control group.In addition,the levels of VEGF in peripheral blood was detected in 15 min before anesthesia induction,1 h during operation,2 h and 1 d after operation,respectively.Then The expression of VEGF in patients with peripheral blood levels was quantified based on the principle of determination of enzyme-linked immunosorbent assay(ELISA)specially,with double antibody sandwich ELISA method.Results 1.There was no significant difference in demographic data,vital signs,dose of intravenous anesthesia between the two groups.MMSE score was significantly lower 2 h after operation than that before operation in experiment group(P < 0.001),but there was no significant difference between pre-operation and post-operation in the control group.As for the variations of VEGF level,it significantly increased 2h after operation in POCD group compared with that in control group,the significant is obvious(P <0.01).However,there was no significant changes between the control group and experiment group in 1d before anesthesia induction,1h during operation and 1d after operation,respectivelyConclusion For the elderly patients undergoing orthopaedics operation under general anesthesia,the early postoperative cognitive decline was associated with the elevated expression of VEGF in peripheral blood 2h after operation.