Interleukin-33 ameliorates perioperative neurocognitive disorders by modulating microglial state.

Perioperative neurocognitive disorders (PND) are cognitive dysfunctions that usually occur in elderly patients after anesthesia and surgery. Microglial overactivation is a key underlying mechanism. Interleukin-33 (IL-33) is a member of the IL-1 family that orchestrates microglial function. In the present study, we explored how IL-33, which regulates microglia, contributes to cognitive improvement in a male mouse model of PND. An exploratory laparotomy was performed to establish a PND model. The expression levels of IL-33 and its receptor ST2 were evaluated using Western blot. IL-33/ST2 secretion, microglial density, morphology, phagocytosis of synapse, and proliferation, and dystrophic microglia were assessed using immunofluorescence. Synaptic plasticity was measured using Golgi staining and long-term potentiation. The Morris water maze and open field test were used to evaluate cognitive function and anxiety. Hippocampal expression of IL-33 and ST2 were elevated on postoperative day 3. We confirmed that IL-33 was secreted by astrocytes and neurons, whereas ST2 mainly colocalized with microglia. IL-33 treatment induced microgliosis after anesthesia and surgery. These microglia had larger soma sizes and shorter and fragmented branches. Compared to the Surgery group, IL-33 treatment reduced the synaptic phagocytosis of microglia and increased microglial proliferation and dystrophic microglia. IL-33 treatment also reversed the impaired synaptic plasticity and cognitive function caused by anesthesia and surgery. In conclusion, these results indicate that IL-33 plays a key role in regulating microglial state and synaptic phagocytosis in a PND mouse model. IL-33 treatment has a therapeutic potential for improving cognitive dysfunction in PND.

Effects of opioid-free anaesthesia on postoperative nausea and vomiting in patients undergoing video-assisted thoracoscopic surgery (OFA-PONV trial): study protocol for a randomised controlled trial.

BACKGROUND: Postoperative nausea and vomiting (PONV) is a common complication after general anaesthesia and is associated with morbidity and prolonged length of stay. Growing evidence suggest that opioid-free general anaesthesia (OFA) may reduce PONV in various surgical settings. We aim to evaluate the efficacy of OFA on the incidence of PONV compared with opioid-based anaesthesia among adults undergoing thoracoscopic surgery. METHODS: This is a prospective, single-centre, randomised controlled trial comparing OFA and opioid-based anaesthesia for thoracoscopic surgery. A total of 168 adults will be randomised with a 1:1 ratio to receive either opioid-free anaesthesia or opioid-based anaesthesia. The primary outcome will be the incidence of PONV within 24 h after operation. The secondary outcomes will include the severity of PONV, quality of recovery, pain at rest, 6-min walking test, and health-related quality of life after operation. DISCUSSION: The benefit-risk of OFA for patients after operation is contradictory in previous studies, so further study is required. This trial will focus on the effect of OFA on the incidence of PONV in patients undergoing thoracoscopic surgery. This trial adopts uniformed PONV and perioperative pain management, standardised randomised and blind, clear-cut inclusion and exclusion criteria, and standardised scales to assess the severity of PONV after surgery, the quality of postoperative recovery, and the health status at 6 months. The findings of this study will help to provide references to promote early recovery of patients after lung surgery. TRIAL REGISTRATION: ClinicalTrials.gov NCT05411159. Registered on 9 June 2022.

Transforming Growth Factor ß1 Ameliorates Microglial Activation in Perioperative Neurocognitive Disorders.

Perioperative neurocognitive disorder (PND) is a common complication of surgery and anesthesia, especially among older patients. Microglial activation plays a crucial role in the occurrence and development of PND and transforming growth factor beta 1 (TGF-ß1) can regulate microglial homeostasis. In the present study, abdominal surgery was performed on 12-14 months-old C57BL/6 mice to establish a PND model. The expression of TGF-ß1, TGF-ß receptor 1, TGF-ß receptor 2, and phosphor-smad2/smad3 (psmad2/smad3) was assessed after anesthesia and surgery. Additionally, we examined changes in microglial activation, morphology, and polarization, as well as neuroinflammation and dendritic spine density in the hippocampus. Behavioral tests, including the Morris water maze and open field tests, were used to examine cognitive function, exploratory locomotion, and emotions. We observed decreased TGF-ß1 expression after surgery and anesthesia. Intranasally administered exogenous TGF-ß1 increased psmad2/smad3 colocalization with microglia positive for ionized calcium-binding adaptor molecule 1. TGF-ß1 treatment attenuated microglial activation, reduced microglial phagocytosis, and reduced surgery- and anesthesia-induced changes in microglial morphology. Compared with the surgery group, TGF-ß1 treatment decreased M1 microglial polarization and increased M2 microglial polarization. Additionally, surgery- and anesthesia-induced increase in interleukin 1 beta and tumor necrosis factor-alpha levels was ameliorated by TGF-ß1 treatment at postoperative day 3. TGF-ß1 also ameliorated cognitive function after surgery and anesthesia as well as rescue dendritic spine loss. In conclusion, surgery and anesthesia induced decrease in TGF-ß1 levels in older mice, which may contribute to PND development; however, TGF-ß1 ameliorated microglial activation and cognitive dysfunction in PND mice.

Pulmonary artery sarcoma: an unexpected settler in the right ventricular outflow tract.

Pulmonary artery sarcoma (PAS) is a sporadic malignant tumor that mainly originates from the pulmonary arteries. However, PAS may also involve the right ventricular outflow tract (RVOT) and lead to obstruction, syncope, or sudden death. Early diagnosis and complete surgical resection are essential to prolong survival and improve the quality of life of patients with PAS. Herein, we report a case of a young female patient admitted for pulmonary malignancy and acute pulmonary embolism. The patient had a mass in the RVOT, which was detected by transthoracic echocardiography. Computed tomography and magnetic resonance imaging revealed the invasion depth and extent of the lesions. Surgical resection improved hemodynamics, while pathological and immunohistochemical tests confirmed the diagnosis of a pulmonary artery sarcoma. Local recurrence was detected in the adjacent tissues about two months after the surgery. Given the potential risk of reoperation, the patient was suggested to undergo conservative treatment.

SIRT1 activation attenuates microglia-mediated synaptic engulfment in postoperative cognitive dysfunction.

Background: Postoperative cognitive dysfunction (POCD) is a debilitating neurological complication in surgical patients. Current research has focused mainly on microglial activation, but less is known about the resultant neuronal synaptic changes. Recent studies have suggested that Sirtuin-1 (SIRT1) plays a critical role in several different neurological disorders via its involvement in microglial activation. In this study, we evaluate the effects of SIRT1 activation in a POCD mouse model. Materials and methods: Exploratory laparotomy was performed in mice aged 12-14 months under sevoflurane anesthesia to establish our animal POCD model. Transcriptional changes in the hippocampus after anesthesia and surgery were evaluated by RNA sequencing. SIRT1 expression was verified by Western Blot. Mice were treated with SIRT1 agonist SRT1720 or vehicle after surgery. Changes in microglia morphology, microglial phagocytosis, presence of dystrophic neurites, and dendritic spine density were evaluated. Cognitive performance was evaluated using the Y maze and Morris water maze (MWM). Results: Sirtuin-1 expression levels were downregulated in POCD. Exposure to anesthesia and surgery lead to alteration in microglia morphology, increased synaptic engulfment, dendritic spine loss, and cognitive deficits. These effects were alleviated by SRT1720 administration. Conclusion: This study suggests an important neuroprotective role for SIRT1 in POCD pathogenesis. Increasing SIRT1 function represents a promising therapeutic strategy for prevention and treatment of POCD.

Anomalous Levels of CD47/Signal Regulatory Protein Alpha in the Hippocampus Lead to Excess Microglial Engulfment in Mouse Model of Perioperative Neurocognitive Disorders.

Background: Perioperative neurocognitive disorders (PNDs) are common complications of surgical patients, which can lead to prolonged hospitalization, increased complications, and decreased independence and quality of life. However, the underlying molecular mechanisms of PND remain largely obscure. Microglia activation and synapse loss were observed in PND. Cluster of differentiation 47 (CD47), which can bind to its receptor signal regulatory protein alpha (SIRPα) and generate "do not eat me" signal, protects synapses from excessive pruning. Therefore, we aimed to evaluate the potential role of CD47-SIRPα signaling in PND. Methods: The tibial fracture surgery was performed in aged C57BL/6 mice for PND model establishment. The expression of CD47 and SIRPα in the hippocampus was assessed. Synaptic plasticity, dendritic spine density, microglial engulfment, and hippocampal-dependent memory function were evaluated after model establishment and intervention with SIRPα overexpression. Results: CD47 and SIRPα expression in the hippocampus were both decreased after the surgery. SIRPα overexpression showed reduced engulfment within host microglia, but a total effect of excessive synapse engulfment decreased dendritic spine density and post-synaptic density protein 95 (PSD95) expression. SIRPα overexpression could not improve the synaptic dysfunction and cognitive impairment in PND. In addition, SIRPα overexpression led to increased CD47 and Iba1 expression. Conclusion: Anesthesia and surgery affect CD47-SIRPα signaling. SIRPα overexpression could not ameliorate the cognitive impairment in PND mice. One reason may be that the increased Iba1 expression leads to a total effect of excessive synapse engulfment, which results in decreased dendritic spine density and PSD95 expression.

Role of BDNF/ProBDNF Imbalance in Postoperative Cognitive Dysfunction by Modulating Synaptic Plasticity in Aged Mice.

Postoperative cognitive dysfunction (POCD) is a disturbing neurological complication in patients undergoing anesthesia and surgical procedures. Brain-derived neurotrophic factor (BDNF) and its precursor proBDNF binding to their corresponding receptors tyrosine kinase (TrkB) and p75 neurotrophin receptor (p75NTR) exert quite an opposite biological function in neuron survival and synaptic function. This study aimed to demonstrate the critical role of the BDNF/proBDNF ratio in modulating synaptic plasticity, which further leads to anesthesia-/surgery-induced POCD. It also showed that the exogenous BDNF or p75NTR inhibitor could ameliorate cognitive dysfunction. In detail, 16-month-old C57BL/6 mice were subjected to a stabilized tibial fracture surgery with isoflurane anesthesia to establish the POCD animal model. The mice were then microinjected with either p75NTR inhibitor or exogenous BDNF into the dorsal hippocampus. Behavioral experiments were performed by open field and fear conditioning tests (FCTs). Western blotting was also used to measure the expression levels of BDNF, proBDNF, TrkB, p-TrkB, p75NTR, and synapse proteins. Golgi staining and electrophysiology were applied to evaluate the neuronal synaptic plasticity. Here, we demonstrated that anesthesia/surgery induced a reduction of BDNF/proBDNF, which negatively regulates the synaptic function in hippocampus, subsequently leading to cognitive impairment in aged mice. P75NTR inhibitor and exogenous BDNF could attenuate cognitive deficits by rescuing the dendritic spine loss and long-term potentiation (LTP) via altering the BDNF/proBDNF ratio. This study unveiled that the BDNF/proBDNF ratio in the hippocampus played a key role in anesthesia-/surgery-induced POCD. Thereby, tuning the ratio of BDNF/proBDNF is supposed to be a promising therapeutic target for POCD.

The effect of intravenous ketamine on depressive symptoms after surgery: A systematic review.

STUDY OBJECTIVE: The development of depressive symptoms is an important complication experienced by patients postoperatively and is associated with poor clinical outcomes. Ketamine is a feasible treatment option for depressive symptoms after surgery due to its known antidepressant effect. This meta-analysis aimed to evaluate the current body of research regarding the effects of intravenous ketamine on depressive symptoms after surgery. DESIGN: A meta-analysis of randomized controlled trials. SETTING: Perioperative care area. PATIENTS: Adult surgical patients. MEASUREMENTS: Systematic literature search was performed in the CENTRAL, MEDLINE, and EMBASE databases, for randomized controlled trials comparing the effect of intravenous ketamine versus placebo on postoperative depressive symptoms as the primary outcome, with no language restrictions. Two independent reviewers screened records for inclusion, extracted data, and assessed risk of bias. Random effects models were used to pool overall estimates. Postoperative pain intensity was also examined. The GRADE approach was used to assess the quality of evidence. MAIN RESULTS: Out of 834 records screened, 9 studies met our inclusion criteria, comprising a total of 2468 patients. Compared with the control group, ketamine provided significant reduction of postoperative depression scale scores, by a standardized mean difference (SMD) of -0.89 (95% CI [-1.23, -0.73], P = 0.33, I2 = 13%; 4 studies) on postoperative day (POD) 1, SMD -0.51 (95% CI [-0.99, -0.04], P < 0.001, I2 = 93%; 4 studies) on POD 3, suggesting clinically relevant reduction in postoperative depressive symptoms. Postoperative depression scale scores on POD 7 were also reduced in patients receiving ketamine compared to the control group, with SMD -0.33 (95% CI [-0.52, -0.14], P = 0.36, I2 = 2%; 3 studies), but the minimal clinical difference of 0.5 SMD was not reached. No significant difference was observed in the postoperative depression scale over the long term at 30 days' follow-up (SMD -0.13, 95% CI [-0.25, 0.00], P = 0.07, I2 = 52%; 5 studies). A significant reduction of postoperative pain intensity on POD 1 was identified in patients following ketamine administration (SMD -1.29, 95% CI [-2.57, -0.01], P = 0.05, I2 = 98%; 5 studies). However, administration of ketamine resulted in a significantly increased risk of nausea and vomiting (RR 1.71, 95% CI [1.25, 2.33], P = 0.17, I2 = 35%; 6 studies), headache (RR 4.88, 95% CI [1.97, 12.06], P = 0.83, I2 = 0%; 4 studies), and hallucination (RR 34.94, 95% CI [8.59, 142.17], P = 0.44, I2 = 0%; 4 studies). CONCLUSIONS: The current evidence supports intravenous ketamine administration for the treatment of depressive symptoms after surgery. While ketamine administration has clinically significant side effects, future studies are needed in surgical populations at high risk of complications.

Activation of CD200-CD200R1 Axis Attenuates Perioperative Neurocognitive Disorder Through Inhibition of Neuroinflammation in Mice.

Perioperative neurocognitive disorder (PND) is the mild cognitive impairment associated with surgery and anesthesia. It is a common surgical complication in the elderly. An important mechanism of PND is the surgically induced neuroinflammation. The interaction between the neuronal surface protein CD200 and its receptor in microglia, CD200R1, is an important regulatory pathway to control neuroinflammation. However, the potential role of the CD200-CD200R1 pathway in the acute period of PND has not been fully investigated. In this study, in a PND mouse model, we first measured the protein expression level of CD200, CD200R1, and the related pro- and anti-inflammatory cytokines in the hippocampus. Then, we investigated cognitive function, neuroinflammation and postsynaptic density protein 95 (PSD-95) expression after the injection of CD200-Fc (agonist), CD200R1-Fc (antagonist) or IgG1-Fc (vehicle) into lateral ventricle in PND models. Compared with the control group, the expression of CD200 was up-regulated at day 1 after surgery in PND models. The injection of the CD200-Fc into the lateral ventricle could mitigate primed neuroinflammation and cognitive decline, increase the expression of PSD-95 at day 1 after surgery in PND models. In conclusion, we have demonstrated that CD200-CD200R1 signaling was involved in the acute inflammatory process of PND, and activating CD200R1 can inhibit neuroinflammation and attenuate PND. Thus, the CD200-CD200R1 axis is a potential novel target for PND prevention and treatment.

Intravenous versus inhalational maintenance of anesthesia for quality of recovery in adult patients undergoing non-cardiac surgery: A systematic review with meta-analysis and trial sequential analysis.

BACKGROUND: Intravenous and inhalational agents are commonly used in general anesthesia. However, it is still controversial which technique is superior for the quality of postoperative recovery. This meta-analysis aimed at comparing impact of total intravenous anesthesia (TIVA) versus inhalational maintenance of anesthesia on the quality of recovery in patients undergoing non-cardiac surgery. METHODS: We systematically searched EMBASE, PubMed, and Cochrane library for randomized controlled trials (RCTs), with no language or publication status restriction. Two authors independently performed data extraction and assessed risk of bias. The outcomes were expressed as mean difference (MD) with 95% confidence interval (CI) based on a random-effect model. We performed trial sequential analysis (TSA) for total QoR-40 scores and calculated the required information size (RIS) to correct the increased type I error. RESULTS: A total of 156 records were identified, and 9 RCTs consisting of 922 patients were reviewed and included in the meta-analysis. It revealed a significant increase in total QoR-40 score on the day of surgery with TIVA (MD, 5.91 points; 95% CI, 2.14 to 9.68 points; P = 0.002; I2 = 0.0%). The main improvement was in four dimensions, including "physical comfort", "emotional status", "psychological support" and "physical independence". There was no significant difference between groups in total QoR-40 score (P = 0.120) or scores of each dimension on POD1. The TSA showed that the estimated required information size for total QoR-40 scores was not surpassed by recovered evidence in our meta-analysis. And the adjusted Z-curves did not cross the conventional boundary and the TSA monitoring boundary. CONCLUSION: Low-certainty evidence suggests that propofol-based TIVA may improve the QoR-40 score on the day of surgery. But more evidence is needed for a firm conclusion and clinical significance.

Perioperative Sleep Disorder: A Review.

Patients in the perioperative period usually present with different types and degrees of sleep disorders, which can severely affect their post-operative outcomes. Multiple risk factors may lead to the occurrence of perioperative sleep disorders, including personal factors, psychological factors, surgery factors, and environmental factors. In this review, we summarize the potential risk factors for perioperative sleep disorders during hospitalization. And it also provides an overview of perioperative outcomes and potential therapeutic prevention of perioperative sleep disorders. However, the further search is necessary to investigate the effectiveness and safety of preventions in the clinical practice and push forward the therapies.

Ginkgolide B­mediated therapeutic effects on perioperative neurocognitive dysfunction are associated with the inhibition of iNOS­mediated production of NO.

Perioperative neurocognitive dysfunction (PND) is a prevalent neurological complication after anesthesia and surgery. Ginkgolide B (GB) has been suggested to improve lipopolysaccharide­induced learning and memory impairment. The present study aimed to investigate whether GB serves a protective role against PND by inhibiting inducible nitric oxide synthase (iNOS) and nitric oxide (NO). Abdominal surgery was performed on 10­ to 12­week­old male C57BL/6 mice under isoflurane anesthesia. Prior to surgery, 1400W (a specific iNOS inhibitor) and GB were administered via intraperitoneal injection. Open field and fear conditioning tests were conducted to assess cognitive function on postoperative days 1 and 3. Biochemical assays were performed to evaluate alterations in NO, malondialdehyde (MDA) and superoxide dismutase (SOD) levels. Western blotting was performed to measure iNOS expression in the hippocampus on postoperative day 1. In addition, hematoxylin and eosin staining was performed to detect the neuronal morphology in the hippocampus. Following treatment with 1400W or GB, surgery­induced cognitive dysfunction was improved. Compared with the control group, the surgery group exhibited significant overproduction of iNOS and MDA in the hippocampus on postoperative day 1. Higher levels of NO were also detected in the hippocampus and prefrontal cortex of the surgery group on postoperative day 1. Furthermore, pretreatment with 1400W or GB significantly inhibited the surgery­induced elevation of NO and MDA in brain tissues. Moreover, GB pretreatment significantly inhibited surgery­induced downregulation of SOD and upregulation of iNOS. Surgery­induced increases in neuronal loss and the Bax/Bcl­2 ratio in the hippocampus were significantly inhibited by pretreatment with GB. Collectively, the results of the present study demonstrated that the therapeutic effects of GB on PND were associated with inhibition of iNOS­induced NO production, increased SOD, and the alleviation of neuronal loss and apoptosis.

Effect of Dexmedetomidine on Postoperative Sleep Quality: A Systematic Review.

In this article, we conduct a systematic review of the literature to explore the specific role of dexmedetomidine (DEX) on postoperative sleep and its associated mechanisms at present. The electronic database Embase, MEDLINE/PubMed, the Cochrane Library, Web of Science, and Google Scholar were searched. The restriction terms included "dexmedetomidine", "sleep" and "surgery". The inclusion criteria were as following: 1) patients 18 years old or older; 2) DEX used in the perioperative period not just for critically ill patients in the intensive care unit (ICU); 3) prospective or retrospective studies. The review articles, conference abstracts, and animal studies were excluded. Out of the 22 articles which met the above criteria, 20 of them were randomized controlled studies and 2 of them were retrospective cohort studies. Infusion of DEX including during the surgery and after surgery at a low or high dose was shown to improve subjective and objective sleep quality, although 2 studies showed there is no evidence that the use of DEX improves sleep quality and 1 showed less sleep efficiency and shorter total sleep time in the DEX group. Other postoperative outcomes evaluated postoperative nausea and vomiting, pain, postoperative delirium bradycardia and hypotension. Outcomes of our systematic review showed that DEX has advantages in improving patients' postoperative sleep quality. Combined with the use of general anesthetic, DEX provides a reliable choice for procedural sedation.

LncRNA NONMMUT055714 acts as the sponge of microRNA-7684-5p to protect against postoperative cognitive dysfunction.

Postoperative cognitive dysfunction (POCD) is a neurological complication of surgery especially common in elderly patients. In this study, we investigated the role of NONMMUT055714 in POCD via regulation of miR-7684-5p. In a POCD mouse model, we induced overexpression of NONMUTT055714 via transfection of lentivrus into the hippocampus, and used the Morris water maze for assessment of cognitive function. Silencing of NONMUTT055714 and miR-7684-5p was induced in primary hippocampal neurons to observe the effects of these regulatory RNAs on cellular processes. Bioinformatics analysis and a double luciferase reporter experiment were performed to further explore the relationship between NONMMUT055714, miR-7684-5p, and SORLA. Cell and animal rescue experiments were performed to verify the ability of miR-7684-5p to reverse the protective effects of NONMMUT055714 overexpression in POCD. We observed that NONMMUT055714 has decreased expression in the POCD mouse model. Overexpression of NONMMUT055714 protected against cognitive impairment of the POCD mouse model in vivo. We identified miR-7684-5p as a NONMMUT055714-related miRNA and in turn as an upstream regulator of SORLA. We found that NONMMUT055714 downregulation is associated with decreased SORLA, increased Aß and p-tau expression, increased inflammatory biomarkers, increased markers of oxidative stress, and increased neuronal apoptosis in vitro. The effects of NONMMUT055714 downregulation were reversed by silencing miR-7684-5p in vitro and in vivo. Taken together, our findings suggest that NONMMUT055714 is protective against the development of POCD via its function as a ceRNA (or miRNA sponge) in the regulation of miR-7684-5p and SORLA. We therefore propose NONMMUT055714 as a novel target for the investigation and prevention of POCD.

The Association of Insomnia with Depression and Anxiety Symptoms in Patients Undergoing Noncardiac Surgery.

OBJECTIVE: Insomnia is common in patients undergoing surgery. It can increase the rate of postoperative complications, interfere with patient recovery, and decrease hospital satisfaction. However, there are few studies on perioperative insomnia. This study was conducted to investigate the differences in the demographic, health status, and clinical characteristics of patients with and without insomnia postoperatively, and to identify the potential risk factors of insomnia. METHODS: There were 299 non-cardiac surgery patients, 165 females, and 134 males, with a mean age of 55 years, enrolled in the study. The Insomnia Severity Index (ISI), Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder 7 (GAD-7), and Montreal Cognitive Assessment (MoCA) were administered to all the patients preoperatively. The Visual Analogue Scale (VAS) was used preoperatively, and at the end of the surgery, and then one day, two days, and three days after surgery. The PHQ-9, the GAD-7, and the ISI were repeated three days after surgery. Insomnia was diagnosed by the ISI as being a score of 8-28 (mild: 8-14; moderate-severe: 15-21; severe: 22-28). The patients were divided into group A (with insomnia, N=78) and group B (without insomnia, N=221) according to their ISI score three days after surgery. The general clinical data of the two groups were analyzed first, and then binary logistic regression analysis was conducted to assess the risk factors of insomnia. RESULTS: A total of 299 non-cardiac surgery patients with a mean age of 55 years were enrolled in the study. Of the included patients, the number of females was 165 and the number of the male was 134. The incidence of insomnia at 3 days postoperatively was 26.1% (78/299). The average points that group A patients scored in the ISI, PHQ-9, and the GAD-7 were significantly higher than those in group B. The VAS score three days after surgery was significantly higher in group A. The PHQ-9 and the GAD-7 three days after surgery showed significantly higher depression and anxiety scores in group A. Logistic regression showed that the ISI (p<0.001, 95% CI=1.218-1.500) and the GAD-7 (p=0.003, 95% CI=1.041-1.218) preoperatively, and the PHQ-9 postoperatively (p<0.001, 95% CI=1.226-1.555), were risk factors of insomnia. CONCLUSION: Insomnia is common and can worsen after surgery. The present study suggests that depression and anxiety are risk factors for insomnia after surgery. There is a need for further research and the development of strategies for depression and anxiety management to ensure better sleep quality for patients, which will be of significant benefit to their health. CLINICAL TRIAL REGISTRATION: The study was registered at clinical trial (NCT04027751); Trial registration: clinical trial, NCT04027751. Registered 22 July 2019; https://clinicaltrials.gov/ct2/show/NCT04027751?cond=NCT04027751&cntry=CN&draw=2&rank=1.

Effect of perioperative intravenous lidocaine on the incidence of short-term cognitive function after noncardiac surgery: A meta-analysis based on randomized controlled trials.

OBJECTIVES: Postoperative cognitive dysfunction is a debilitating postoperative complication. The perioperative neuroprotective effect of lidocaine has conflicting results. METHODS: In this qualitative review of randomized controlled clinical trials on the perioperative use of lidocaine, we report the effects of intravenous lidocaine on brain function after noncardiac surgery. Studies were identified from PubMed, MEDLINE, and Cochrane Central Register. RESULTS: Of the 453 retrieved studies, 4 randomized trials were included. No significant association between the use of lidocaine postoperative cognitive states was found (risk ratio 0.67; 95% CI -0.02 to 1.36; I2 89%; p = .06). CONCLUSIONS: Current evidence cannot suggest that perioperative intravenous use of lidocaine has pharmacological brain neuroprotection after noncardiac surgery. All the included studies were small-scale research, and the total number of participants was small; the results should be interpreted with caution.

Atorvastatin protects against postoperative neurocognitive disorder via a peroxisome proliferator-activated receptor-gamma signaling pathway in mice.

OBJECTIVE: Postoperative neurocognitive disorder (PND) is a main complication that is commonly seen postoperatively in elderly patients. The underlying mechanism remains unclear, although neuroinflammation has been increasingly observed in PND. Atorvastatin is a pleiotropic agent with proven anti-inflammatory effects. In this study, we investigated the effects of atorvastatin on a PND mouse model after peripheral surgery. MATERIAL AND METHODS: The mice were randomized into five groups. The PND models were established, and an open field test and fear condition test were performed. Hippocampal inflammatory cytokine expression was determined using ELISA. Peroxisome proliferator-activated receptor-gamma (PPARγ) expression in the hippocampus was tested using qRT-PCR and western blot analysis. RESULTS: On day 1 after surgery, inflammatory cytokines such as tumor necrosis factor-α, interleukin-1ß, and interleukin-6 showed a significant increase in the hippocampus, with prominent cognitive impairment. Atorvastatin treatment improved cognitive function in the mouse model, attenuated neuroinflammation, and increased PPARγ expression in the hippocampus. However, treatment with the PPARγ antagonist GW9662 partially reversed the protective effects of atorvastatin. CONCLUSIONS: These results indicated that atorvastatin improves several hippocampal functions and alleviates inflammation in PND mice after surgery, probably through a PPARγ-involved signaling pathway.

RAGE antagonism by FPS­ZM1 attenuates postoperative cognitive dysfunction through inhibition of neuroinflammation in mice.

Neuroinflammation triggered by surgical trauma contributes to postoperative cognitive dysfunction (POCD). The receptor for advanced glycation end­products (RAGE), a multiligand inflammatory receptor, is involved in the damaging effects of various cellular processes, contributing to neuroinflammation and neurodegeneration. However, the potential role of RAGE in the acute period of POCD has not been fully investigated. C57BL/6 male mice undergoing surgery of the tibia under isoflurane anesthesia were treated with the RAGE antagonist FPS­ZM1 or vehicle control intraperitoneally for a period of 7 days. The cognitive function of the animals was tested using trace fear conditioning on the third postoperative day. To determine astrocytic activation, microgliosis, p65 expression, inflammatory factor levels and postsynaptic density protein­95 (PSD­95) expression in the hippocampus, the animals were euthanized on either the first, third or seventh postoperative day. Compared with the control group, the cognitive function of the surgical animals was impaired on the third postoperative day. Astrocytic activation, microgliosis and the expression levels of p65, interleukin (IL)­1ß, IL­6, and PSD­95 were significantly increased on the first, and third postoperative days. However, tumor necrosis factor­α expression was significantly increased only on postoperative day 1. All of the surgical effects observed were partially inhibited by treatment with FPS­ZM1. In summary, the results of the present study suggest that RAGE serves an important role in the acute inflammatory process of POCD, and blocking RAGE can inhibit neuroinflammation and attenuate POCD. Thus, the RAGE signaling pathway may be a novel target in the prevention, and treatment of POCD.

MiR-7684-5p leads to surgery-induced cognitive decline in mice probably through the downregulation of SorLA.

BACKGROUND: Postoperative cognitive dysfunction is a postoperative severe complication caused by many factors. However, its specific pathogenesis remains unclear. MicroRNAs (miRNAs), which are involved in the pathogenesis of neurodegenerative diseases, may also affect POCD. METHODS: In this research, microarray technology was used to screen 26 miRNAs that had a differential expression in the hippocampus of mouse between the surgery group and control group. The qRT-PCR verification on the hippocampuses of 10 pairs of mouse testifies the high expression of miR-7684-5p in the surgery group (identical with the result of chip). RESULTS: Surgical trauma was found to induce the expression of miR-7684-5p with the accumulation of Aß in the hippocampus. Furthermore, miR-7684-5p knockdown effectively reduced the levels of Aß triggered by surgery, and attenuated hippocampal-dependent memory impairment. Moreover, we testify that sorLA is a target gene of miR-7684-5p through bioinformatics prediction and dual-luciferase report gene experiment. CONCLUSIONS: Our data indicate that decreased postoperative cognitive function may be caused by the increased generation of Aß by reducing sorLA expression. Our work implicates miR-7684-5p as a potential biomarker and a novel therapeutic target.

Impact of warming blood transfusion and infusion toward cerebral oxygen metabolism and cognitive recovery in the perioperative period of elderly knee replacement.

OBJECTIVE: This study aims to observe the impact of the temperature of blood transfusion and infusion toward the perioperative cerebral oxygen metabolism and the postoperative cognitive recovery. METHODS: Eighty patients of knee replacement under epidural and general anesthesia were randomly divided into warming blood transfusion and infusion (WBI) group (n = 40) and control group (n = 40). The changes of nasopharyngeal temperature, middle cerebral artery blood flow, CERO2, and SjVO2 of the two groups were recorded at each time point for the assessment of the postoperative overall quality of recovery and cognitive recovery situation. RESULTS: The nasopharyngeal temperatures of the two groups at different time points after transfusion were significantly lower than that at T1, and there was a significant difference between the two groups (P < 0.05). The CERO2 values of the two groups at T3 were significantly higher than at T1, while the SjVO2 values were significantly decreased (P < 0.01). CONCLUSION: The WBI can significantly reduce the occurrence of the perioperative hypothermia, while it has no significant effect toward cerebral oxygen metabolism, postoperative overall recovery, and recovery of cognitive function.