Objective:To evaluate the relationship between the severity of preoperative brain injury and postoperative delirium (POD) in elderly patients using latent class analysis based on markers of brain injury.Methods:One hundred and thirty-one American Society of Anesthesiologists Physical Status classification Ⅰ-Ⅲ patients, aged 65-84 yr, with a body mass index of 18-28 kg/m 2, scheduled for elective unilateral total hip arthroplasty in our hospital, were selected. Cognitive function was assessed using the Mini-Mental State Examination before surgery. Arterial blood samples were collected before anesthesia to measure the plasma concentrations of brain-derived neurotrophic factor, inducible nitric oxide synthase, prostaglandin E2, central nervous system-specific protein (S100β), glial fibrillary acidic protein, neurofilament light chain, matrix metalloproteinase-9, fibroblast growth factor 23, complement 3, complement 3a, complement 5a and irisin using enzyme-linked immunosorbent assay. POD was evaluated using the Confusion Assessment Method within 3 days after operation, and the patients were divided into POD group and non-POD group. The patients were divided into different injury severity subtypes based on the levels of brain injury markers using latent class analysis, and logistic multivariate regression was used to analyze the independent risk factors for POD. Results:Compared with non-POD group, the concentrations of neurofilament light chain, glial fibrillary acidic protein, S100β and prostaglandin E2 were significantly different in POD group ( P<0.05). Using these four brain injury markers for latent class analysis, patients were divided into a high severity of brain injury group (91.51%) and a low severity of brain injury group (8.49%). The results of logistic multivariate regression analysis showed that subtypes of brain injury ( OR=8.31, 95% confidence interval [ CI] 1.77-38.90, P=0.007), age ( OR=1.14, 95% CI 1.03-1.24, P=0.007), and plasma irisin concentrations ( OR=0.99, 95% CI 0.98-0.99, P=0.027) were independent risk factors for POD. Conclusions:Higher severity of preoperative brain injury is an independent risk factor for POD in elderly patients.

Machine learning(ML)technology has been gradually applied in clinical anesthesia,and the application and research in the perioperative period are increasing.ML can warn occurrence of high-risk events,assist the diagnosis of difficult airway and ultrasound imaging in the perioperative period.Intrao-peratively,ML can predict hypotension,hypoxemia,cardiac arrest,and depth of anesthesia to help achieve precise and safe control of anesthesia.Postoperatively,ML can predict anesthesia-related adverse outcomes.This article summarizes the ML models commonly used in the field of anesthesiology,and reviews the rele-vant studies of ML application in all stages of the perioperative period.The application of ML can improve the perioperative anesthesia management,help to warn the occurrence of high-risk events and reduce anes-thesia-related risks.

Patients undergoing bariatric surgery are often accompanied by moderate to severe post-operative pain,and the application of high-dose opioids after surgery is more likely to cause adverse reac-tions such as respiratory depression,nausea and vomiting.Multimodal analgesia strategy based on ultrasound-guided regional nerve block has gradually shown outstanding advantages in the pain management of bariatric surgery,which can effectively reduce the dosage of opioids,reduce the incidence of postoperative complications,and improve the quality of postoperative recovery.In recent years,the applica-tion of different regional nerve block methods in bariatric surgery has been reported.This article reviews the characteristics of pain after laparoscopic bariatric surgery,the application,effects and limitations of different nerve block techniques,so as to provide reference for clinical application.

Objective To observe the effect of ciprofol on hemodynamics in elderly patients with left ventricular diastolic dysfunctionfrom induction of anesthesia to incision.Methods Eighty-two elderly patients,42 males and 40 females,aged 65-90 years,BMI 18.5-30.0 kg/m2,ASA physical status Ⅱ or Ⅲ,undergoing non-cardiac surgery under elective general anesthesia were enrolled.The patients were ran-domly divided into two groups:ciprofol group(group C)and propofol group(group P),41 patients in each group.Anesthesia induction was performed using ciprofol at a dose of 0.3 mg/kg in group C or propofol at a dose of 1.5 mg/kg in group P.The number of patients with hypotension between anesthesia induction and skin incision were recorded.HR,SBP,DBP,and cardiac index(CI)were recorded immediately before an-esthesia induction(T0),3 minutes after induction(T1),immediately after tracheal intubation(T2),3 mi-nutes after tracheal intubation(T3),5 minutes after tracheal intubation(T4),and 10 minutes after tracheal intubation(T5).Intraoperative use of vasoactive drugs,the incidence of injection pain,bucking,movement and bradycardia from induction of anesthesia to incision were recorded.The occurrence of adverse reactions such as postoperative agitation,nausea and vomiting within 48 hours after surgery were also recor-ded.Results Compared with group P,the incidence of hypotension in group C from induction of anesthesia to incision was significantly decreased(P<0.05).Compared with T0,HR at T1—T5 in the two groups slowed down significantly(P<0.05),and SBP,DBP,and CI were significantly decreased(P<0.05).Compared with group P,CI in group C was significantly higher at T5(P<0.05),and the incidence of in-jection pain was significantly decreased(P<0.05).There was no significant difference in HR,SBP and DBP between two groups at different time points.There was no significant differences in the rates of ephed-rine,phenylephrine and atropine,bucking,intraoperative movement,bradycardia,postoperative agitation and nausea and vomiting within 48 hours after surgery between the two groups.Conclusion Ciprofol has a smaller impact on the hemodynamics of elderly patients with left ventricular diastolic dysfunction and can be safely used for anesthesia induction in elderly patients undergoing non-cardiac surgery.

Objective To investigate the correlation between oral frailty and POD in elderly patients undergoing non-cardiac surgery.Methods A total of 268 elderly patients,115 males and 153 fe-males,aged ≥ 65 years,BMI 14-36 kg/m2,ASA physical status Ⅱ or Ⅲ,undergoing elective non-cardiac surgery from February 2023 to July 2023 were selected.The oral frailty index-8(OFI-8)was used to measure the oral frailty status of patients one day before surgery.The 3-minute delirium diagnostic scale(3D-CAM)was used to evaluate the occurrence of POD 1,2,3 days after surgery.The patients were divid-ed into delirium group(POD group)and non-delirium group(non-POD group)according to whether POD occurred 3 days after surgery.Multivariate logistic regression model was used to analyze the relationship be-tween oral frailty and POD.Results POD occurred in 61 patients(22.7％).Multivariate logistic regression analysis showed that postoperative use of analgesic pump(OR=2.298,95％CI 1.034-5.108,P=0.041)and oral frailty(OR=2.295,95％CI 1.193-4.415,P=0.012)are significantly correla-ted with the occurrence of POD,after adjusting for age,ASA physical status,hemoglobin,anesthesia time and infusion volume.Conclusion The incidence of postoperative POD in elderly patients with preoperative oral weakness is significantly increased undergoing non-cardiac surgery,and preoperative oral weakness is correlated with the occurrence of POD.

The intensifying aging of the population has led to a growing severity of multimorbidity,significantly impacting patients'quality of life.Current anesthetic management approaches primarily target individual diseases,which struggle to effectively address the complexity of multimorbidity.This article re-views the concept and research status of multimorbidity,analyzes the interconnections among aging,multi-morbidity,and frailty,and discusses the influence of multimorbidity on perioperative risks.For patients with multimorbidity,the article proposes perioperative management strategies encompassing preoperative assess-ment,multidisciplinary collaboration,personalized anesthesia plans,intraoperative monitoring,and postop-erative care.Furthermore,the article underscores the shift from single-disease assessments to comprehensive multimorbidity assessment frameworks,and explores novel management models utilizing big data and artificial intelligence to enhance surgical safety and improve patient prognosis.

Objective To analyze the effect of different anesthesia induction time on postoperative circadian rhythm in patients undergoing robot-assisted radical prostatectomy.Methods A total of 103 pa-tients,aged 50-85 years,BMI 18-30 kg/m2,ASA physical status Ⅰ-Ⅲ,undergoing robot-assisted radi-cal prostatectomy from January 2022 to October 2022 were recruited.The patients were grouped according to the induction time:the morning 8:00-11:59 group(group M,n=53)and the afternoon 12:00-18:00 group(group A,n=50).D'Amico risk grade,duration of anesthesia,number of effective com-pressions of analgesic pump(D1)and actual compressions(D2)were recorded,D1/D2 were calculated.HR,MAP,SpO2 were recorded at 5 minutes after entrying the operation room(T0),5 minutes after anes-thesia induction(T,),5 minutes after the surgery start(T2),60 minutes after the surgery start(T3),at the end of surgery(T4)and 5 minutes after extubation(T5).BIS at T1-T4 were recorded.Sleeping status was assessed by the Athens insomnia scale(AIS)1 day before surgery,1 day and 3 days after surgery,and pain level was assessed 1 and 3 days after surgery using the digital rating scale(NRS).According to the re-sults of the morningness-eveningness questionnaire of sleep-wake assessment(MEQ-SA)1 day before surgery and 3 days after surgery,the patients'circadian rhythm was determined.Results There were no statistically significant differences in D'Amico risk grade,duration of anesthesia,D1/D2,HR,MAP,SpO2 and BIS at different time point,AIS scores 1 day before surgery,1 day and 3 days after surgery,and NRS scores 1 day and 3 days after surgery between the two groups.In group M,there were 11 cases(21％)of circadian rhythm changes,of which 5 people's circadian rhythm changed to"later"and 6 people's circadian rhythm changed to"earlier".In group A,there were 3 cases(6％)of circadian rhythm changes,of which 1 person's circadian rhythm changed to"later"and 2 people's circadian rhythm changed to"earlier".The rate of circadian rhythm change in group M was significantly higher than that in group A(P＜0.05).Conclusion The incidence of perioperative circadian rhythm alteration is significantly higher in patients undergoing robot-assisted radical prostatectomy who starts anesthesia in the morning than those in the after-noon.

Vagus nerve is the main undertaker of the parasympathetic nervous system,participating in the regulation of inflammatory response and playing the role of organ function protection.Stimulation such as perioperative operation and anesthesia can often lead to a relative decrease in vagus nerve tension and in-crease in perioperative circulation,respiration,digestion,nerve,and other system-related complications.This article mainly reviews the effects of reduced vagal tone on perioperative multiple organ functions and va-gus nerve stimulation in organ function,aiming to provide new ideas for reducing various perioperative com-plications.

Sevoflurane is a commonly used inhalation anesthetic in childrenjs general anesthesia, which may have some adverse effects on brain development. This review discusses the effects of sevoflurane anesthesia on developing brain, based on the characteristics of developing brain tissue, the effects on developing brain function, the mechanism of sevoflurane neurotoxicity and the strategies to reduce sevoflurane anesthesia neurotoxicity, so as to provide reference for clinical application.

Objective　To investigate the role of the p75 neurotrophic receptor (p75 NTR) in the cognitive impairment induced by laparotomy surgery of aged mice,and to explore the possible mechanism.Methods　Thirty eighteen-month-old male mice were equally randomized into three groups (n=10):control group,surgery group,surgery+TAT group.Open field test was performed 5 days after the surgery to record the exploration distance and the time in the center.Fear-conditioned training was performed 6 days after the surgery,and fear-conditioned test was performed 7 days after the surgery to record the freezing time.The hippocampus was harvested immediately after the behavioral test.Western blot was applied to detect the levels of p75NTR,BDNF,PSD95,TrkB and pCREB in the hippocampus,immunofluorescence was applied to detect the number of caspase-3 positive cells in the hippocampus,and Golgi staining was applied to observe the changes of dendritic spines in hippocampal CA-1 region.Results　In the open field test,the total distance and the time in the center had no significant difference among the three groups (P>0.05).In the fear conditioning test,compared with control group,the percentage of the contextual conditional freezing time decreased significantly in surgery group (P<0.05),and the expressions of BDNF，PSD95，TrkB and pCREB and the number of dendritic spines in CA-1 were significantly decreased (P<0.05),the expression of p75NTR and the number of caspase-3 positive cells were increased significantly in the surgery group (P<0.05).Compared with the surgery group,the percentage of the contextual conditional freezing time increased significantly in surgery+TAT group,and the expressions of BDNF,PSD95,TrkB,and pCREB and the number of dendritic spines in CA-1 were significantly increased,the number of caspase-3 positive cells were decreased significantly in the surgery+TAT group (P<0.05).Conclusion　Hippocampal p75 NTR plays a key role in the pathophysiology of POCD.