The Effect Of Anesthetic Management Based On Intraoperative Regional Cerebral Oxygen Saturation On Postoperative Delirium In Elder Patients Underwent Hip Replacement

ObjectivePostoperative delirium(POD)is an acute brain injury after the operation which performs a disturbance in attention and cognition.The cognitive changes are embodied in impaired memory,shifting attention,disability of direction or sustainability.It is common in elderly patients especially.Not only influencing the recovery from the operation,POD could also increase the cost of the whole hospitalization,the length of hospital stays,the incidence of dementia and,importantly,mortality.Near-Infrared spectroscopy(NIRS)is a technique that can reveal the intraoperative cerebral oximetry.At the same time,it could work in real time,noninvasively and bedside.It would emit near-infrared rays through the probes which were placed on the patient’s forehead and arrived at the brain tissue through the skin and skull.Due to the different absorption spectra of hemoglobin in the brain tissue under different oxidation states,cerebral oxygen saturation can be obtained.In recent years,the monitoring of cerebral oxygen saturation is mainly used in heart,nerve,carotid artery surgery and beach chair position surgery to reduce the risk of cerebral ischemia and hypoxia.However,there is not enough study to confirm the association between cerebral oxygen saturation and POD.Our hypothesis was that the lower intraoperative rSO2 would disturb the neurocognitive function and increase the incidence of PODMethodsThis was a randomized controlled trial(registered with http://www.hictr.org.cn[ChiCTR2000037492]).After the permission of Ethics Committee of Shandong Provincial Hospital,we recruited target population that were suitable for this study and randomly assigned to receive either intraoperative regional cerebral oxygen saturation-guided care or usual care.The incidence of POD was evaluated with the help of RASS and CAM.We recorded some secondary outcomes including the first time to have an activity,first time to diet after operation,sleep quality,the length of hospital stays after the surgery and mortality.We detected the relationship between regional cerebral oxygen saturation and POD.We also attempted to find other risk factors through this study.Results152 patients were recruited and 80 were divided into regional cerebral oxygen saturation-guided care group and 72 into usual care group.14 patients developed POD in regional cerebral oxygen saturation-guided care group(17.5%)and 10 in usual care group(13.9%)(OR 1.315,95%CI 0.544-3.178,p=0.542).The area under the curve(AUC)of the regional cerebral oxygen saturation-guided care group was significantly smaller than usual care group(left,0 VS.6%*min,p=0.011;right,0 VS.68%*min,p=0.004).Older patients(OR 1.248,95%CI1.026-1.519,p=0.027),lower baseline rSO2 value(OR 0.847,95%CI0.722-0.994,p=0.042),ICU admission after surgery(OR 18.968,95%CI 1.710-210.449,p=0.017)were identified as the risk factors of POD.Conclusions1.The anesthetic management based on the intraoperative regional cerebral oxygen saturation could not decrease the incidence of the postoperative delirium in elderly patients underwent hip replacement.2.The anesthetic management based on the intraoperative rSO2 can keep the rSO2 in an ideal range.3.Older patients,lower baseline rSO2 value and ICU admission after surgery might be associated with a higher incidence of POD.