Analysis Of Risk Factors And Plasma Concentrations Of ?-amyloid Peptide, S-100? Of Postoperative Cognitive Dysfunction In Patients Undergoing Oral And Maxillofacial Cancer Surgery

Objective1.To investigate the risk factors of postoperative cognitive dysfunction in elderly patients undergoing oral and maxillofacial cancer surgery.2.To observe the the changes of perioperative plasma concentrations of A?1-40,S-100?,and to discuss their relationship with POCD.MethodsOne hundred and fifteen patients aged at least 60 years undergoing oral and maxillofacial tumor resection surgery were investigated between May to December 2014.Neuropsychological tests for detecting POCD were performed preoperatively,7 days after the surgery.According to the results of neuropsychological tests on day 7,patients were divided into the POCD group and the non-POCD group.We recorded patient's perioperative relevant factors,including:age,sex,body mass index,educational status,ASA grade,left ventricular ejection fraction,history of smoking and drinking,chemotherapy and general anesthesia,preoperative comorbidities,duration of anesthesia,blood loss, whether accept the neck dissection surgery and tracheotomy,intraoperative hypotension, ICU stay, length of postoperative hospital stay,second operation in 7 days after surgry,postoperative complications,benign and malignant tumor ratio.Univariate analyses andmultivariate logistic regression analyses were performed to analysis risk factors of postoperative cognitive dysfunction.We take 5 ml blood from the patients before induction of anesthesia,and on 24 h and day 7 postoperatively(P<0.05). Put the blood samples into 5 ml EDTA anticoagulant tubes and centrifuge them with low temperature and high speed within 30 minutes. Then we take 2 ml of the supernatant in 2 tubes and store the plasma samples in the fridge at the temperature of-80?.Plasma values of A?1-40 and S-100? are determined with ELISA(enzyme linked immunosorbent assay).Results1.According to our definition,POCD was present in 37 of 115(32.3%)patients 1 week after surgery.Logistic regression analysis identified the Independent risk factors for POCD including:advanced age(OR=1.071,95%CI1.003 ~ 1.142,P<0.05),history of hypertention(OR=0.267,95%CI 0.105 ~0.676,P<0.01),prolonged duration of anesthesia(OR=1.003,95%CI 1.000 ~1.006,P<0.05),length of hospital stay(OR=1.071,95%CI 1.008 ~1.138,P<0.025).2.Compared with the pre-anesthesia,S-100? levels in POCD group were significantly increased(P <0.05);the levels of A?1-40 were significantly higher than preoperatively at 24 h after surgery(P <0.05). Compared with non-POCD group, S-100 ? levels were significantly increased on 24 h postoperatively(P <0.05);A?1-40 levels were significantly higher on 24 h and day 7 postoperatively(P<0.05).Conclusions1.The study found the incidence of POCD of elderly patientsis was 32.2%at 7 days after undergoing oral and maxillofacial surgery with generalanesthesia.Advanced age,history of hypertension,prolonged anesthesia and postoperative length of hospital stay are the independent risk factors for postoperative cognitive dysfunction with oral cancer patients.2.The increasing levels of A?1-40, S-100?may be associated with the incidence of POCD after the oral cancer surgery.Patients with long lasting and high concentrations of A ? 1-40 and S-100 ? after the surgery,the occurrence of POCD will be increased.3.The clinical values of A?1-40 and S-100 as predictive measurements of POCD after oral and maxillofacial cancer surgery appear to be suitable.But it still needs further multi-center, larger study sample clinical trials to evaluate.