Recombinant chitinase-3-like protein 1 alleviates learning and memory impairments via M2 microglia polarization in postoperative cognitive dysfunction mice

Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life of patients.To date,there are no viable treatment options for postoperative cognitive dysfunction.The identification of postoperative cognitive dysfunction hub genes could provide new research directions and therapeutic targets for future research.To identify the signaling mechanisms contributing to postoperative cognitive dysfunction,we first conducted Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of the Gene Expression Omnibus GSE95426 dataset,which consists of mRNAs and long non-coding RNAs differentially expressed in mouse hippocampus3 days after tibial fracture.The dataset was enriched in genes associated with the biological process"regulation of immune cells,"of which Chill was identified as a hub gene.Therefore,we investigated the contribution of chitinase-3-like protein 1 protein expression changes to postoperative cognitive dysfunction in the mouse model of tibial fractu re surgery.Mice were intraperitoneally injected with vehicle or recombinant chitinase-3-like protein 124 hours post-surgery,and the injection groups were compared with untreated control mice for learning and memory capacities using the Y-maze and fear conditioning tests.In addition,protein expression levels of proinflammatory factors(interleukin-1βand inducible nitric oxide synthase),M2-type macrophage markers(CD206 and arginase-1),and cognition-related proteins(brain-derived neurotropic factor and phosphorylated NMDA receptor subunit NR2B)were measured in hippocampus by western blotting.Treatment with recombinant chitinase-3-like protein 1 prevented surgery-induced cognitive impairment,downregulated interleukin-1βand nducible nitric oxide synthase expression,and upregulated CD206,arginase-1,pNR2B,and brain-derived neurotropic factor expression compared with vehicle treatment.Intraperitoneal administration of the specific ERK inhibitor PD98059 diminished the effects of recombinant chitinase-3-like protein 1.Collectively,our findings suggest that recombinant chitinase-3-like protein 1 ameliorates surgery-induced cognitive decline by attenuating neuroinflammation via M2 microglial polarization in the hippocampus.Therefore,recombinant chitinase-3-like protein1 may have therapeutic potential fo r postoperative cognitive dysfunction.

Anesthesia,Anesthetics,and Postoperative Cognitive Dysfunction in Elderly Patients

Postoperative cognitive dysfunction(POCD)remains a major issue that worsens the prognosis of elderly surgery patients.This article reviews the current research on the effect of different anesthesia methods and commonly utilized anesthetics on the incidence of POCD in elderly patients,aiming to provide an understanding of the underlying mechanisms contributing to this condition and facilitate the development of more reasonable anesthesia protocols,ultimately reducing the incidence of POCD in elderly surgery patients.

Impact of thoracic paravertebral block and sufentanil on outcomes and postoperative cognitive dysfunction in thoracoscopic lung cancer surgery

BACKGROUND Postoperative pain management and cognitive function preservation are crucial for patients undergoing thoracoscopic surgery for lung cancer(LC).This is achieved using either a thoracic paravertebral block(TPVB)or sufentanil(SUF)-based multimodal analgesia.However,the efficacy and impact of their combined use on postoperative pain and postoperative cognitive dysfunction(POCD)remain unclear.AIM To explore the analgesic effect and the influence on POCD of TPVB combined with SUF-based multimodal analgesia in patients undergoing thoracoscopic radical resection for LC to help optimize postoperative pain management and improve patient outcomes.METHODS This retrospective analysis included 107 patients undergoing thoracoscopic radical resection for LC at The Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital between May 2021 and January 2023.Patients receiving SUF-based multimodal analgesia(n=50)and patients receiving TPVB+SUF-based multimodal analgesia(n=57)were assigned to the control group and TPVB group,respectively.We compared the Ramsay Sedation Scale and visual analog scale(VAS)scores at rest and with cough between the two groups at 2,12,and 24 h after surgery.Serum levels of epinephrine(E),angio-tensin Ⅱ(Ang Ⅱ),norepinephrine(NE),superoxide dismutase(SOD),vascular endothelial growth factor(VEGF),transforming growth factor-β1(TGF-β1),tumor necrosis factor-α(TNF-α),and S-100 calcium-binding proteinβ(S-100β)were measured before and 24 h after surgery.The Mini-Mental State Examination(MMSE)was administered 1 day before surgery and at 3 and 5 days after surgery,and the occurrence of POCD was monitored for 5 days after surgery.Adverse reactions were also recorded.RESULTS There were no significant time point,between-group,and interaction effects in Ramsay sedation scores between the two groups(P>0.05).Significantly,there were notable time point effects,between-group differences,and interaction effects observed in VAS scores both at rest and with cough(P<0.05).The VAS scores at rest and with cough at 12 and 24 h after surgery were lower than those at 2 h after surgery and gradually decreased as postoperative time increased(P<0.05).The TPVB group had lower VAS scores than the control group at 2,12,and 24 h after surgery(P<0.05).The MMSE scores at postoperative days 1 and 3 were markedly higher in the TPVB group than in the control group(P<0.05).The incidence of POCD was significantly lower in the TPVB group than in the control group within 5 days after surgery(P<0.05).Both groups had elevated serum E,Ang Ⅱ,and NE and decreased serum SOD levels at 24 h after surgery compared with the preoperative levels,with better indices in the TPVB group(P<0.05).Marked elevations in serum levels of VEGF,TGF-β1,TNF-α,and S-100β were observed in both groups at 24 h after surgery,with lower levels in the TPVB group than in the control group(P<0.05).CONCLUSION TPVB combined with SUF-based multimodal analgesia further relieves pain in patients undergoing thoracoscopic radical surgery for LC,enhances analgesic effects,reduces postoperative stress response,and inhibits postoperative increases in serum VEGF,TGF-β1,TNF-α,and S-100β levels.This scheme also reduced POCD and had a high safety profile.

Small extracellular vesicles secreted by induced pluripotent stem cell-derived mesenchymal stem cells improve postoperative cognitive dysfunction in mice with diabetes

Postoperative cognitive dysfunction(POCD)is a common surgical complication.Diabetes mellitus(DM)increases risk of developing POCD after surgery.DM patients with POCD seriously threaten the quality of patients’life,however,the intrinsic mechanism is unclear,and the effective treatment is deficiency.Previous studies have demonstrated neuronal loss and reduced neurogenesis in the hippocampus in mouse models of POCD.In this study,we constructed a mouse model of DM by intraperitoneal injection of streptozotocin,and then induced postoperative cognitive dysfunction by transient bilateral common carotid artery occlusion.We found that mouse models of DM-POCD exhibited the most serious cognitive impairment,as well as the most hippocampal neural stem cells(H-NSCs)loss and neurogenesis decline.Subsequently,we hypothesized that small extracellular vesicles secreted by induced pluripotent stem cell-derived mesenchymal stem cells(iMSC-sEVs)might promote neurogenesis and restore cognitive function in patients with DM-POCD.iMSC-sEVs were administered via the tail vein beginning on day 2 after surgery,and then once every 3 days for 1 month thereafter.Our results showed that iMSC-sEVs treatment significantly recovered compromised proliferation and neuronal-differentiation capacity in H-NSCs,and reversed cognitive impairment in mouse models of DM-POCD.Furthermore,miRNA sequencing and qPCR showed miR-21-5p and miR-486-5p were the highest expression in iMSC-sEVs.We found iMSC-sEVs mainly transferred miR-21-5p and miR-486-5p to promote H-NSCs proliferation and neurogenesis.As miR-21-5p was demonstrated to directly targete Epha4 and CDKN2C,while miR-486-5p can inhibit FoxO1 in NSCs.We then demonstrated iMSC-sEVs can transfer miR-21-5p and miR-486-5p to inhibit EphA4,CDKN2C,and FoxO1 expression in H-NSCs.Collectively,these results indicate significant H-NSC loss and neurogenesis reduction lead to DM-POCD,the application of iMSC-sEVs may represent a novel cell-free therapeutic tool for diabetic patients with postoperative cognitive dysfunction.

Adaptive and regulatory mechanisms in aged rats with postoperative cognitive dysfunction

Inflammation may play a role in postoperative cognitive dysfunction. 5＇ Adenosine monophos- phate-activated protein kinase, nuclear factor-kappa B, interleukin-1β, and tumor necrosis factor-a are involved in inflammation. Therefore, these inflammatory mediators may be involved in postoperative cognitive dysfunction. Western immunoblot analysis revealed 5＇ adenosine mo- nophosphate-activated protein kinase and nuclear factor-kappa B in the hippocampus of aged rats were increased 1-7 days after splenectomy. Moreover, interleukin-1β and tumor necrosis fac- tor-α were upregulated and gradually decreased. Therefore, these inflammatory mediators may participate in the splenectomy model of postoperative cognitive dysfunction in aged rats.

Aspartic acid in the hippocampus:a biomarker for postoperative cognitive dysfunction

This study established an aged rat model of cognitive dysfunction using anesthesia with 2% iso- flurane and 80% oxygen for 2 hours. Twenty-four hours later, Y-maze test results showed that isoflurane significantly impaired cognitive function in aged rats. Gas chromatography-mass spectrometry results showed that isoflurane also significantly increased the levels of N,N-diethy- lacetamide, n-ethylacetamide, aspartic acid, malic acid and arabinonic acid in the hippocampus of isoflurane-treated rats. Moreover, aspartic acid, N,N-diethylacetamide, n-ethylacetamide and malic acid concentration was positively correlated with the degree of cognitive dysfunction in the isoflurane-treated rats. It is evident that hippocampal metabolite changes are involved in the formation of cognitive dysfunction after isoflurane anesthesia. To further verify these results, this study cultured hippocampal neurons in vitro, which were then treated with aspartic acid （100 μmol/L）. Results suggested that aspartic acid concentration in the hippocampus may be a biomarker for predicting the occurrence and disease progress of cognitive dysfunction.

Correlation Analysis Between BDNF and Postoperative Cognitive Dysfunction in Aged Rats

Objective:To investigate the relationship between BDNF and postoperative cognitive dysfunction among aged rats.Methods:36 SPF healthy aged male SD rats were randomly assigned to a control group and a model group,respectively,with 18 rats in each group.Abdominal exploration was performed on the rats in the model group after anesthesia,while the rats in the control group were not operated on after anesthesia.The escape latency and swimming distance of the two groups were analyzed on a day prior to surgery as well as on the first day,third day,and seventh day following surgery;the expression levels of BDNF protein in the hippocampus of rats in the two groups were compared on the first day,third day,and seventh day following surgery;the correlation between BDNF and escape latency and swimming distance was analyzed.Results:The escape latency and swimming distance of the rats in the control group on a day prior to surgery,the first day,third day,and seventh day following surgery did not differ significantly(p>0.05),but those in the model group had significant behavioral difference(p<0.05).On a day prior to surgery,the rats in both groups showed no significant behavioral difference in escape latency and swimming distance(p>0.05),but on the first day,third day,and seventh day following surgery,the escape latency and swimming distance of the rats in the model group were significantly longer than those in the control group(p<0.05).In the control group,there was no significant difference in the protein expression of BDNF in the hippocampus of rats on the first day,third day,and seventh day following surgery,but there was significant difference in the model group.On the first day,third day,and seventh day following surgery,the BDNF protein expression level in the rats’hippocampus of the control group was significantly higher than that of the model group(p<0.05).The data from Pearson correlation analysis confirmed that BDNF protein expression is negatively correlated with escape latency(r=-0.567,p<0.001)and swimming distance(r=-0.623,p<0.001).Conclusion:In aged rats,the BDNF protein expression level decreases,and the degree of cognitive dysfunction increases after surgery.

Effects of ulinastatin combined with dexmedetomidine on cognitive dysfunction and emergence agitation in elderly patients who underwent total hip arthroplasty

BACKGROUND With the continuous growth of the modern elderly population,the risk of fracture increases.Hip fracture is a common type of fracture in older people.Total hip arthroplasty(THA)has significant advantages in relieving chronic pain and promoting the recovery of hip joint function.AIM To investigate the effect of ulinastatin combined with dexmedetomidine(Dex)on the incidences of postoperative cognitive dysfunction(POCD)and emergence agitation in elderly patients who underwent THA.METHODS A total of 397 patients who underwent THA from February 2019 to August 2022.We conducted a three-year retrospective cohort study in Shaanxi Provincial People’s Hospital.Comprehensive demographic data were obtained from the electronic medical record system.We collected preoperative,intraoperative,and postoperative data.One hundred twenty-nine patients who were administered Dex during the operation were included in the Dex group.One hundred fifty patients who were intravenously injected with ulinastatin 15 min before anesthesia induction were included in the ulinastatin group.One hundred eighteen patients who were administered ulinastatin combined with Dex during the operation were included in the Dex+ulinastatin group.The patients’perioperative conditions,hemodynamic indexes,postoperative Mini-Mental State Examination(MMSE)scores,Ramsay score,incidence of POCD,and serum inflammatory cytokines were evaluated.RESULTS There was a significant difference in the 24 h visual analogue scale score among the three groups,and the score in the Dex+ulinastatin group was the lowest(P<0.05).Compared with the Dex and ulinastatin group,the MMSE scores of the Dex+ulinastatin group were significantly increased at 1 and 7 d after the operation(all P<0.05).Compared with those in the Dex and ulinastatin groups,incidence of POCD,levels of serum inflammatory cytokines in the Dex+ulinastatin group were significantly decreased at 1 and 7 d after the operation(all P<0.05).The observer’s assessment of the alertness/sedation score and Ramsay score of the Dex+ulinastatin group were significantly different from those of the Dex and ulinastatin groups on the first day after the operation(all P<0.05).CONCLUSION Ulinastatin combined with Dex can prevent the occurrence of POCD and emergence agitation in elderly patients undergoing THA.

Investigation of one-lung ventilation postoperative cognitive dysfunction and regional cerebral oxygen saturation relations

Objective： To explore the relationship of postoperative cognitive dysfunction （POCD） in one-lung ventilation （OLV） patients and regional cerebral oxygen saturation （rSO2）. Methods： Twenty-nine male and twenty-one female cases of OLV received thoracic surgery, with American Standards Association （ASA） physical status being at Grades Ⅰ-Ⅲ. Neuropsychological tests were performed on the day before operation and 7 d after operation, and there was an intraoperative continuous monitoring of rSO2. The values of rSO2 before anesthesia induction （t1）, at the beginning of OLV （t2）, and at the time of OLV 30 min （t3）, OLV 60 min （t4）, the end of OLV （t5）, and the end of surgery （t6） were recorded. The intraoperative average of rSO2 （ rSO2 ）, the intraoperative minimum value of rSO2 （rSO2, rn=n）, and the reduced maximum percentage of rSO2 （rSO2, %max） when compared with the baseline value were calculated. The volume of blood loss, urine output, and the amount of fluid infusion was recorded. Results： A total of 14 patients （28%） in the 50 cases suffered from POCD. The values of mini-mental state examination （MMSE）, the digit span and the digit symbol on the 7th day after the operation for POCD in OLV patients were found to be significantly lower than those before the operation （P〈0.05）. The values of MMSE and vocabulary fluency scores were significantly lower than those in the non-POCD group （P〈0.05）. The values of rSO2 in the POCD group of OLV patients at t2 and t3 and the values of rSO2 in the non-POCD group at t2 were found to be significantly higher than those at tl （P〈0.05）. The values of rSO2, %max in the POCD group were significantly higher than those in the non-POCD group （P〈0.05）. When the value of rSO2, %max is more than 10.1%, it may act as an early warning index for cognitive function changes, Conclusions： POCD after OLV may be associated with a decline in rSO2.

Serum proteomics of early postoperative cognitive dysfunction in elderly patients

Background Studies on postoperative cognitive dysfunction （POCD） have attracted extensive attention and achieved significant progress. However, the diagnosis of POCD is not very satisfactory as no specific biomarkers have been classified. The aim of the present study was to evaluate differences in serum protein composition between POCD and Non-POCD patients, identify potential biomarkers associated with early POCD, and study the mechanism underlying POCD. Methods Sixty-eight elderly patients （age 〉65 years） received isoflurane inhalation anesthesia for arthroplasty surgeries. One day before and seven days after the surgery, these patients were subjected to a neuropsychological test and venous blood sample collection. Postoperative cognitive dysfunction was determined using Z test scores. Based on the results, the patients were divided into POCD and non-POCD groups. Twenty-five randomly chosen blood samples obtained seven days after the surgery from each group were analyzed on a Bruker ultraFlexTM time of flight （TOF）/TOF mass spectrophotometer. The resulting peptide fingerprints were compared with those from the pre-surgery samples to identify differences in serum protein composition. The model designed to distinguish between a non-POCD group and a POCD group were established and validated. Three proteins with the most significant changes were selected for further characterization. Results Thirty-three cases were diagnosed as POCD. Using the Clinprotools software, 58 polypeptides were found to display differential expression （P 〈0.05）. Using a support vector algorithm method, seven differential peaks were isolated to establish a diagnostic model to distinguish POCD patients from normal individuals. The prediction rate and recognition rate were 96.89% and 100%, respectively. Validation of this model showed that the accuracy rates were 100% and 85% using samples from the POCD and non-POCD groups, respectively. Protein analysis also led to the identification of fibrinopeptide A （FPA） as a potential biomarker for POCD. Conclusions Arthroplastic surgery under isoflurane inhalation anesthesia causes differential serum protein expression in elderly patients. These differentially expressed proteins may contribute to the diagnosis of early POCD, which may provide a basis for identifying the underlying mechanism of POCD development.

Postoperative delirium:A tragedy for elderly cancer patients

In this editorial,we comment on the article by Hu et al entitled“Predictive modeling for postoperative delirium in elderly patients with abdominal malignancies using synthetic minority oversampling technique”.We wanted to draw attention to the general features of postoperative delirium(POD)as well as the areas where there are uncertainties and contradictions.POD can be defined as acute neurocognitive dysfunction that occurs in the first week after surgery.It is a severe postoperative complication,especially for elderly oncology patients.Although the underlying pathophysiological mechanism is not fully understood,various neuroinflammatory mechanisms and neurotransmitters are thought to be involved.Various assessment scales and diagnostic methods have been proposed for the early diagnosis of POD.As delirium is considered a preventable clinical entity in about half of the cases,various early prediction models developed with the support of machine learning have recently become a hot scientific topic.Unfortunately,a model with high sensitivity and specificity for the prediction of POD has not yet been reported.This situation reveals that all health personnel who provide health care services to elderly patients should approach patients with a high level of awareness in the perioperative period regarding POD.

Cognitive clarity in colon surgery: The dexmedetomidine advantage

Colon cancer is one of the most prevalent cancers globally,especially in the older age group.A large number of older patients undergoing surgery for colon cancer suffer from postoperative cognitive dysfunction(POCD).The trial by Bu et al demonstrated that dexmedetomidine(Dex)significantly reduced the incidence of POCD compared to placebo in individuals undergoing colon cancer surgery.Additionally,better cerebral oxygenation and lower cerebral injury markers were reported with the use of Dex.The trial has some limitations,such as a single-center design and a smaller sample size,and further studies with larger patient populations and robust multi-center designs are warranted to establish these findings.

The role of anesthesia in peri-operative neurocognitive disorders:Molecular mechanisms and preventive strategies

Peri-operative neurocognitive disorders(PNDs)include postoperative delirium(POD)and postoperative cognitive dysfunction(POCD).Children and the elderly are the two populations most vulnerable to the development of POD and POCD,which results in both high morbidity and mortality.There are many factors,including neuroinflammation and oxidative stress,that are associated with POD and POCD.General anesthesia is a major risk factor of PNDs.However,the molecular mechanisms of PNDs are poorly understood.Dexmedetomidine(DEX)is a useful sedative agent with analgesic properties,which significantly improves POCD in elderly patients.In this review,the current understanding of anesthesia in PNDs and the protective effects of DEX are summarized,and the underlying mechanisms are further discussed.

Transcutaneous Electrical Acupoint Stimulation Improves Postoperative Cognitive Function in Senior Patients Undergoing Video-Assisted Thoracoscopic Surgery:A Randomized Controlled Trial

Objective:To evaluate the effectiveness and safety of transcutaneous electrical acupoint stimulation(TEAS)for improving postoperative cognitive function in senior patients undergoing video-assisted thoracoscopic surgical(VATS).Methods:From January to December 2020,97 participants were randomly assigned to the TEAS group(49 cases)and the control group(48 cases)by a random number table.The patients in the TEAS group received TEAS,at the bilateral Neiguan(PC 6)and Zusanli(ST 36)acupoints.The control group received sham TEAS.The stimulation was started from 30 min before surgery until the end of the operation.The primary outcome was the incidence of pstoperative cognitive dysfunction(POCD),diagnosed based on the changes in the Mini-Mental Status Examination(MMSE)and Montreal Cognitive Assessment(MoCA)scores.The secondary outcomes were plasma levels of S100β protein and neuron-specific enolase(NSE).Results:The incidence of POCD on day 1 and 3 after surgery in the TEAS group was significantly lower than that in the control group[day 1 after surgery:28.3%(13/46)vs.52.3%(23/44),P=0.028;day 3 after surgery:21.7%(10/46)vs.40.9%(18/44),P=0.043].Compared with baseline,the MMSE and MoCA scores decreased to various extents in both groups.The MMSE scores on day 1,3,and 5 after surgery and MoCA scores on day 1,3,5,and 7 after surgery in the TEAS group were higher than those in the control group(all P<0.05)in both groups.Compared with baseline,the plasma levels of S100β and NSE were significantly increased at 4,8,12,24 h after surgery(all P<0.05).Compared with the control group,the plasma levels of S100β and NSE were lower in the TEAS group at 4,8,12,and 24 h after surgery(all P<0.05).No obvious adverse events were found during the trial.Conclusion:Application of TEAS in senior patients after VATS could reduce incidence of POCD and improve postoperative cognitive function.

The effect of electroacupuncture preconditioning on cognitive impairments following knee replacement among elderly:A randomized controlled trial

Objective: To investigate if electroacupuncture(EA) preconditioning can mitigate cognitive impairments and reduce the incidence of postoperative cognitive dysfunction(POCD) following knee replacement and its safety among elderly.Methods: Totally 60 participants met the inclusion criteria were enrolled in a randomized controlled trial a ratio of 1:1, with 30 cases allocated to the treatment group and 30 cases allocated to the control group, respectively. The participants in the treatment group were provided with real-EA therapy whereas participants in control group were provided with placebo-EA therapy(Streitberger Placebo-needle). In both groups, Tou sanshen(头三神)acupoints, including Sìshéncōng(四神聪EX-HN1), Sh6 ntíng(神庭 GV24),and bilateral Běnsh6 n(本神GB13) were adopted as the main acupoints, while Bǎihui(百会GV20), bilateral Hégǔ(合谷Ll4), and bilateral Tàich6 ng(太冲LR3) were adopted as matching acupoints. Interventions were offered 5 days prior to the surgery, once daily, and continued for total 5 days. The global scores of MiniMental State Examination(MMSE), and levels of serum inflammatory cytokines including interleukin 1β(IL-1β) and tumor necrosis factor-α(TNF-α), and S100-β protein were observed at 24 h prior to the surgery, and postoperative 24 and 72 h respectively for assessing the incidence of POCD and the severity of cognitive impairments among patients. Meanwhile, adverse effects were monitored and recorded.Results:(1) Compared with baseline, MMSE global scores in both treatment and control groups markedly decreased at postoperative 24 h. MMSE global scores in treatment group decreased from 29.43 ±0.97 to27.10 ±1.95 while that in control group decreased from 29.27 ± 1.01 to 26.83 ± 2.25(all ?P< 0.05), and this trend continued until postoperative 72 h(at postoperative 72 h, MMSE global scores in treatment group was 26.53 ±2.26 versus 24.79 ±3.03 in control group). Moreover, decline in control group was more significant than that in treatment group at postoperative 72 h(P<0.05).(2) Compared with baseline, levels of serum IL-1β, TNF-α and S100-β in both groups increased markedly at postoperative 24 and 72 h. IL-1β in treatment group increased from 43.13 ±5.51 to 73.13 ±2.32 at postoperative 24 h and reached 83.17 士 5.95 at postoperative 72 h, while IL-1β in control group increased from 44.87 土 5.83 to91.10 ±3.55 at postoperative 24 h and reached 111.93 ±9.18 at postoperative 72 h;TNF-α in treatment group increased from 51.27 士 6.48 to 88.80 ± 3.55 at postoperative 24 h and reached 94.37 ± 5.22 at postoperative 72 h, while TNF-α in control group increased from 52.07 ±7.48 to 116.37 ±3.14 at postoperative24 h and reached 121.40 ±3.68 at postoperative 72 h(both ?P< 0.05), furthermore, increases of IL-1β and TNF-α levels in control group were more significant(P<0.05). Statistical difference in level of S100-β was not observed(P>0.05).(3) There was no statistical difference in POCD incidence at postoperative 24 h and postoperative 72 h between two groups(P> 0.05), though the incidence of POCD in patients receiving real-EA therapy was indeed much lower than that in patients receiving placebo-EA therapy, particularly at postoperative 72 h(POCD incidence rate at postoperative 24 h in treatment group was 26.67%, 30.00%in control group;POCD incidence rate at postoperative 72 h in treatment group was 30.00%, 46.67% in control group).(4) No serious adverse events were reported in this trial. No one dropped out from this trial.Conclusion: EA preconditioning can mitigate cognitive impairments at post-knee replacement surgery 24 and 72 h in elderly through inhibiting expression of inflammation. However, there is insufficient evidence to support that EA pretreatment can reduce the incidence of POCD.

硝普钠控制性降压对老年全髋置换术后认知功能的影响

Objestive To investigate the effects of nitroprusside induced hypotension on cognitive function after total hip replacement and the serum S-100 level in reflecting postoperative cognitive dysfunction (POCD). Methods Forty patients (age>65 yr) undergoing total hip replacement were assigned to two groups, randomly. In one group, the mean arterial pressure was decreased about 30% by sodium nitroprusside. In another group, the MAP was set constant as control. Serum values of S-100 were determined preoperatively and 0 2 h and 24 h postoperatively. Neuropsychological tests (Mini-Mental State Examination MMSE) for detecting POCD were performed preoperatively and the 4th day after the operation. A decline of more than 2 scores in MMSE results was regarded as POCD. Results According to our definition, 7 patients had POCD. There were no significant differences in MMSE test in two groups (P>0.05). Those patients had POCD showed higher serum concentrations of S-100 than those without POCD, especially at 0, 2 h postoperatively (P<0.05). Conclusion Nitroprusside induced hypotension would not impair cognitive function in old patients after total hip arthroplasty. S-100 appears to be suitable in the assessment or incidence of cognitive dysfunctions postoperatively.