Application of Acupuncture to Attenuate Immune Responses and Oxidative Stress in Postoperative Cognitive Dysfunction: What Do We Know So Far?

Associations between postoperative cognitive dysfunction, serum interleukin-6 and postoperative delirium among patients after coronary artery bypass grafting: A mediation analysis

BACKGROUND

POCD is a common complication among patients who underwent coronary artery bypass graft (CABG), it is linked to loss of independence and reduced quality of life.

AIMS AND OBJECTIVES

To examine the association between postoperative cognitive dysfunction (POCD), postoperative delirium (POD) and interleukin-6 (IL-6).

DESIGN

A prospective cohort study.

METHODS

Patients who underwent elective isolated CABG were enrolled. POCD was assessed by a set of cognitive function tools. Delirium was assessed using the CAM-ICU. The logistic regression analyses were used to identify the predictive value of POD or IL-6 on POCD. The path analysis was used to analyse the relationship among POD, IL-6 and POCD.

RESULTS

A total of 212 patients were enrolled, with 25.0% of patients developing POD and 32.5% developing POCD. The multiple logistic regression analysis revealed that patients with POD had a four-fold increased hazard of POCD (OR = 3.655), and patients with IL-6 ≥ 830.50 pg/mL at the 6th hours after surgery had a 5-fold increased risk of experiencing POCD (OR = 5.042). However, the mediation effect of POD between IL-6 and POCD was not statistically significant (β = 0.059, p = .392).

CONCLUSIONS

POD and IL-6 at the 6th hour after surgery (≥830.50 pg/mL) are two potent predictors for POCD, while POD did not play a mediation effect between IL-6 and POCD.

RELEVANCE TO CLINICAL PRACTICE

Early identification of risk factors (e.g., delirium assessment and testing for serum IL-6 levels) by clinical nurses for POCD may contribute to the clinical practice for the targeted prevention nursing strategies.

Influence of Neostigmine on Early Postoperative Cognitive Dysfunction in Older Adult Patients Undergoing Noncardiac Surgery: A Double-Blind, Placebo-Controlled, Randomized Controlled Trial

BACKGROUND

The goal of this study was to investigate the efficacy of neostigmine on postoperative cognitive dysfunction (POCD) and determine its effect on systematic markers of oxidative stress in older patients.

METHODS

This double-blind placebo-controlled trial enrolled 118 elderly patients (≥65 years) undergoing noncardiac surgeries who were allocated to a neostigmine treatment group (0.04 mg/kg) or a placebo control group (normal saline) postoperatively. POCD was diagnosed if the Z -scores for the mini-mental state examination and the Montreal Cognitive Assessment were both ≤-1.96. Postoperative serum levels of malondialdehyde (MDA), superoxide dismutase (SOD), and brain-derived neurotrophic factor (BDNF) were also compared. Multivariable regression analysis with dose adjustment of atropine was used to demonstrate the influence of neostigmine on the incidence of POCD.

RESULTS

Patients receiving neostigmine had a significantly reduced incidence of POCD compared to patients who were treated with placebo on the first day after surgery (-22%, 95% confidence interval [CI], -37 to -7), but not on the third (8%, 95% CI, -4 to 20) or seventh day after surgery (3%, 95% CI, -7 to 13). Postoperative plasma MDA levels were significantly lower ( P = .016), but SOD and BDNF levels were increased ( P = .036 and .013, respectively) in the neostigmine group compared to the control group on the first day after surgery.

CONCLUSIONS

Neostigmine reduced POCD on the first day after noncardiac surgery in older patients. Neostigmine treatment inhibited oxidative stress and increased serum BDNF levels. There was no significant influence of neostigmine on POCD on the third or seventh day after surgery. The clinical influence of neostigmine on POCD should be further investigated.

Research progress on the association between MicroRNA and postoperative cognitive dysfunction

Postoperative cognitive dysfunction (POCD) is a significant complication following surgery. The precise mechanisms underlying POCD remain elusive, although it is speculated that they involve central nervous system inflammation, oxidative stress and cellular apoptosis. MicroRNAs (miRNAs), a class of non-coding RNAs widely distributed in eukaryotes, have been implicated in the pathogenesis of neurodegenerative disorders and could potentially impact POCD. This review explores the association between miRNAs and POCD and provides an overview of the progress of current research on miRNAs in the pathogenesis, diagnosis, and treatment of POCD.

The impact of "long COVID" on menstruation in Chinese female college students and the intervention of acupuncture

This study aimed to explore the potential application value of acupuncture in alleviating the impact of long COVID on women's menstrual cycles, by investigating the occurrence of long COVID among female college students, its effects on menstruation, and the intervention of acupuncture. This cross-sectional study surveyed female college students with a history of coronavirus disease 2019 (COVID-19) before April 10, 2023. A questionnaire was used to analyze demographic characteristics, post-COVID sequelaes, duration of symptoms, and treatments received during that period. Among the 731 participants enrolled in the survey, 468 were female undergraduate students who met the analysis criteria. Among them, 85 individuals fit the definition of "Long COVID" (18.16%). Within the group of patients with long COVID, 69 individuals experienced changes in their overall menstrual patterns compared to the 6 months prior to contracting the novel coronavirus (81.18%). Additionally, 17 individuals opted for acupuncture treatment following the onset of COVID-19 (20.00%), which resulted in less impact on their menstrual cycle (41.18% vs 64.71% without receiving acupuncture, OR = 2.62), menstrual period duration (41.18% vs 64.71%, OR = 2.62), menstrual flow (47.06% vs 69.18%, OR = 2.52), and the color of menstrual blood (41.18% vs 63.24%, OR = 2.46) among these patients. Long COVID had a certain impact on menstruation. Acupuncture potentially alleviates the clinical symptoms of long COVID and reduces its impact on women's menstrual cycle, thus having potential therapeutic value in the treatment of long COVID.

Effects of conventional nursing in the operating room combined with transcutaneous electrical acupoint stimulation on postoperative cognitive dysfunction after total knee arthroplasty in elderly patients

BACKGROUND

To observe the effects of conventional theatre nursing combined with transcutaneous electrical acupoint stimulation (TEAS) on postoperative cognitive dysfunction (POCD) in elderly total knee arthroplasty (TKA) patients.

METHODS

Forty elderly TKA patients were randomly divided into a conventional nursing (control) group and a TEAS group. Using conventional nursing, TEAS was used to stimulate the "Zusanli" and "Sanyinjiao" in the healthy leg of patients in the TEAS group. All patients received mini-mental (MMSE) scores 1 day before surgery (T0) and 1, 3, and 7 days after surgery (T1, T3, T7). Plasma levels of interleukin-1 (IL-1β), interleukin-6 (IL-6), tumor necrosis factor (TNF-α), and S100β were measured using venous blood samples.

RESULTS

There were no significant differences in baseline clinical characteristics between the two groups. Compared to T0, the MMSE scores of patients in the control group were significantly reduced at T1 and T3 (P < 0.05). Compared to the control group, the MMSE scores of patients in the TEAS group increased significantly at T3 (P < 0.05). The incidence of POCD in the TEAS group was 10%, lower than in the control group (40%) (P < 0.05). The levels of IL-1β, IL-6, TNF-α and S-100β in patients in the TEAS group were lower than in the control group on days T1, T3 and T7 (P < 0.05).

CONCLUSION

Conventional intraoperative nursing combined with TEAS can reduce the incidence of POCD. The possible mechanism is related to the reduction of inflammatory response and neuronal injury with TEAS.

CLINICAL REGISTRATION NUMBER

ChiCTR2300070281.

Acupuncture-related techniques for postoperative cognitive complications: a systemic review and meta-analysis

BACKGROUND

Postoperative cognitive complications are major challenges for postoperative recovery. Acupuncture-related techniques have been used for treating neurocognitive dysfunctions. However, whether they help to prevent postoperative cognitive complicationss remains unclear. We intend to evaluate the effect of acupuncture-related techniques on the incidence of postoperative cognitive complications (PCC) in patients undergoing surgery under general anesthesia.

METHODS

Based on PRISMA guidelines, a search of PubMed, EMBASE, Web of Science, and the Cochrane Central Register of Controlled Trials and ClinicalTrials.gov was performed to identify eligible trials published from inception to June 6, 2021. The search was performed in June 2021. The inclusion criteria were prospective, randomized, controlled clinical trials that compared acupuncture-related techniques with other techniques or non-acupuncture treatment in patients undergoing surgery under general anesthesia. Pooled odds ratios (ORs), 95% CIs, and P values were estimated for end points using fixed and random effects statistical models.

RESULTS

The analysis included 12 studies with 1058 patients. Compared with patients not receiving acupuncture, patients treated with acupuncture-related techniques had a lower incidence of PCCs (OR, 0.44; 95% CI, 0.33 to 0.59; P < 0.001; n = 968) and lower levels of biomarkers, including IL-6, TNF-α, and S100β. Acupuncture with needles and without needles showed similar effects on the prevention of PCCs. The effects of acupuncture-related techniques on PCCs were observed in both English and non-English articles. Subgroup analyses showed that both agitation and/or delirium (OR, 0.51; 95% CI, 0.34 to 0.76; P < 0.001; n = 490) and delayed cognitive recovery (OR, 0.33; 95% CI, 0.21 to 0.51; P < 0.001; n = 478) were reduced after treatment with acupuncture-related techniques. In adult studies evaluating MMSE scores, the scores were not different between groups (SMD, - 0.71; 95% CI, - 1.72 to 0.3; P = 0.17; n = 441).

CONCLUSIONS

Acupuncture-related techniques, including needle techniques and electrical techniques, are associated with fewer postoperative cognitive complications, suggesting that acupuncture could be considered a potential option in the perioperative setting. Additional research is needed to develop higher-quality evidence and optimal regimens.

TRIAL REGISTRATION

PROSPERO (CRD42021258378).

Electroacupuncture ameliorates surgery-induced spatial memory deficits by promoting mitophagy in rats

Background

This study sought to explore the mechanism underlying the therapeutic effects of electroacupuncture (EA) on spatial memory deficits caused by surgery.

Methods

Hepatic apex resection was performed under propofol-based total intravenous anesthesia. Male Sprague-Dawley rats were subjected to EA treatment or EA + mitochondrial division inhibitor-1 (mdivi-1) treatment once a day for three consecutive days after surgery. The Morris water maze test was used to evaluate the spatial memory of the rats after surgery. Tissue from the hippocampus of each rat was frozen and used for transcriptomic and proteomic analyses to identify potential targets for EA treatment. Western blotting was used to confirm the protein expression levels. The levels of reactive oxygen species (ROS) and adenosine triphosphate (ATP) were detected using commercial kits. The rat mitochondria were then isolated, and the activity of mitochondrial complex V was assessed.

Results

EA attenuated surgery-induced spatial memory deficits on postoperative day 3, while these effects were reversed by treatment with the mdivi-1 (P<0.05). Ribonucleic acid (RNA)-sequencing revealed that EA upregulated multiple metabolic pathways and the phosphatidylinositol 3‑kinas/protein kinase B signaling pathway. The proteomic and western blotting results suggested that the EA treatment substantially downregulated coiled-coil-helix-coiled-coil-helix domain containing 3 (ChChd3) expression in the hippocampus. The EA treatment significantly increased the autophagy-related protein levels, including phosphatase and tensin homolog-induced kinase 1, Parkin, MAP1LC3 (LC3), and Beclin1, and inhibited the production of ROS and inflammatory cytokine interleukin-1β in the hippocampus (P<0.05).

Conclusions

These results suggest that EA ameliorates postoperative spatial memory deficits and protects hippocampus from oxidative stress and inflammation through enhanced autophagy in an animal model of perioperative neurocognitive disorders (PNDs).

Transcutaneous electrical acupoint stimulation for the prevention of postoperative delirium in elderly surgical patients: A systematic review and meta-analysis

Objective

This systematic review and meta-analysis aimed to evaluate the preventive effect of transcutaneous electrical acupoint stimulation on postoperative delirium in elderly surgical patients.

Methods

PubMed, CENTRAL, China National Knowledge Infrastructure, and WanFang databases were searched for randomized controlled trials regarding the effect of transcutaneous electrical acupoint stimulation on preventing postoperative delirium in elderly patients undergoing any type of surgery. The primary outcome was the incidence of postoperative delirium. The secondary outcome was the duration of postoperative delirium. All analyses were conducted using RevMan 5.3 and Stata 13.0 software.

Results

Twelve trials with 991 participants were included, and most of them were at high/unclear risk of bias. Meta-analysis showed transcutaneous electrical acupoint stimulation could reduce the incidence of postoperative delirium (RR = 0.40, 95%CI = 0.29 to 0.55, p < 0.00001) and shorten the duration of postoperative delirium (MD = -0.97 days, 95%CI = -1.72 to -0.22, p = 0.01). Subgroup analyses demonstrated that transcutaneous electrical acupoint stimulation reduced the incidence of postoperative delirium in elderly patients undergoing orthopedic surgery and thoracic surgery, but not digestive surgery; transcutaneous electrical acupoint stimulation with dilatational wave and with continuous wave were both beneficial; and transcutaneous electrical acupoint stimulation was favored when compared to blank and sham control.

Conclusion

Transcutaneous electrical acupoint stimulation could reduce the incidence of postoperative delirium and shorten the duration of postoperative delirium in elderly surgical patients. The findings should be interpreted with caution due to weak evidence. High-quality, large sample, and multi-center trials are needed to further confirm the preliminary findings.Systematic review registration: https://inplasy.com/inplasy-2022-7-0096/, identifier: INPLASY202270096.

Acupuncture for mild cognitive impairment: A systematic review with meta-analysis and trial sequential analysis

Background

There is insufficient evidence to support the use of acupuncture for mild cognitive impairment (MCI), and there is no consensus on its efficacy. This review aimed to determine the acupuncture effect in patients with MCI.

Methods

Relevant and potentially eligible randomized controlled trials (RCTs) of acupuncture for MCI were obtained from four Chinese databases, four English databases, and additional resources up to 1 August 2022. The primary outcome was the improvement in overall cognitive function (OCF). Secondary outcomes were improved memory function (MF) and activities of daily living (ADLs). The revised Cochrane collaboration risk of bias (ROB) assessment tool (ROB 2.0) was applied to evaluate their methodological quality. The Review Manager software v 5.4 was used for analyses. Trial sequential analysis (TSA) 0.9.5.10 β software was used to estimate the required sample size and test the reliability of the pooled outcome. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool.

Results

This meta-analysis included 11 RCTs with a total of 602 patients. The methodological quality of all trials was moderate. Low-quality evidence showed that acupuncture significantly improved OCF (Mini-Mental State Examination (MMSE): mean difference (MD) = 1.22, 95% confidence interval (CI): 0.78-1.66; the Montreal Cognitive Assessment Scale (MoCA): MD = 1.22, 95% CI: 0.47-1.97). In subgroup analyses, it was revealed that acupuncture significantly increased OCF in patients with MCI when compared to conventional medicine (CM) and sham acupuncture (SA). TSA's findings indicated that the evidence of improving OCF with acupuncture for patients with MCI was conclusive. Meanwhile, there is no statistical difference in the improvement of MF and ADL between acupuncture and CM. TSA showed that the evidence of improving MF and ADL for patients who had MCI and received acupuncture was inconclusive. The shreds of evidence of improving MF and ADL were ranked from low to critically low.

Conclusion

Acupuncture appears to be an effective clinical application method for improving OCF in patients with MCI. However, due to low-quality evidence, more relevant and high-quality research is needed in this field.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021291284, PROSPERO, No. CRD42021291284.

Mesenchymal Stem Cell-Derived Exosomes Ameliorate Delayed Neurocognitive Recovery in Aged Mice by Inhibiting Hippocampus Ferroptosis via Activating SIRT1/Nrf2/HO-1 Signaling Pathway

Delayed neurocognitive recovery (dNCR) is a prevalent perioperative neurological complication in older patients and has common characteristics such as acute cognitive dysfunction, impaired memory, and inattention. Mesenchymal stem cell-derived exosomes (MSCs-Exo) are enclosed by a lipid bilayer contain proteins, DNA, miRNA, and other components, which are important mediators of intercellular communication. It has been reported that exosomes could play an important role in the treatment of neurodegenerative diseases, nerve injury, and other neurological diseases. In this study, we examined the effects of MSCs-Exo on dNCR aged mice after exploratory laparotomy and evaluated their potential regulatory mechanisms. We found that MSCs-Exo treatment ameliorated cognitive impairment in dNCR aged mice. MSCs-Exo inhibit hippocampus ferroptosis and increase the expression of silent information regulator 1 (SIRT1), factor nuclear factor-erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) in dNCR aged mice. Interestingly, the above effects of MSCs-Exo on dNCR aged mice were abolished by SIRT1 selective inhibitor EX-527. In conclusion, these findings indicated that MSCs-Exo can ameliorate cognitive impairment by inhibiting hippocampus ferroptosis in dNCR aged mice via activating SIRT1/Nrf2/HO-1 signaling pathway, providing a potential avenue for the treatment of dNCR.

Predictors and occurrence of postoperative cognitive dysfunction in children undergoing noncardiac surgery: A prospective cohort study

In children after cardiac surgery, alterations in cognitive ability and behavior are increasingly common, but whether postoperative cognitive dysfunction (POCD) occurs in children undergoing noncardiac surgery is not known. The present study was performed to investigate the incidence rate and potential risk factors of early neurocognitive dysfunction in children after noncardiac surgery. Two hundred patients aged between 4 and 14 years old underwent elective noncardiac surgery and 100 healthy age-matched controls were enrolled in this prospective observational study. Wechsler Preschool and Primary Scale of Intelligence or Wechsler Intelligence Scale for Children-Revised were conducted 1 day before and 3 days after surgery. POCD was calculated and diagnosed as a combined Z score. Any factors that differed between POCD and non-POCD group (p < 0.10) were tested together by multivariate logistic regression analysis against the cognitive outcome of patients, to find out the independent risk factors of POCD. The general incidence of POCD was 15.6%. The univariate analysis revealed that POCD was associated with general anesthesia, surgical and anesthesia duration, early postoperative fever (EPF), and surgical history. However, only the history of surgery (p = 0.029), anesthesia duration (p = 0.010), and EPF (p < 0.001) were demonstrated to be independent risk factors for POCD. The occurrence rate of early POCD after noncardiac surgery in children is 15.6%. Children who had surgical history, longer anesthesia duration, or EPF are more prone to develop POCD.

Effects of Dexmedetomidine Anesthesia on Early Postoperative Cognitive Dysfunction in Elderly Patients

The stimulation of tracheal extraction and anesthesia may lead to early postoperative cognitive dysfunction (POCD) in elderly patients, especially within 72 h after surgery, due to the insufficient compensatory and regulatory effects of their cardiovascular system. This study was performed to demonstrate the effects of additional dexmedetomidine (DEX) administration on alleviating early POCD (72 h post intubation) and inflammation in elderly patients who underwent intubation. A parallel-randomized trial was performed in this study. A total of 100 patients aged 60-85 years were randomly divided into two groups (DEX, n = 50; control, n = 50). They received traditional anesthesia and additional DEX medications. Mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA) were used to assess the cognitive dysfunction of patients. The enzyme-linked immunosorbent assay (ELISA) was used to detect the stress and inflammatory response of the two groups of patients. Administration of DEX significantly improved the MMSE and MoCA scores 24 and 72 h post operation. The S100β and neuron-specific enolase (NSE) levels in serum were downregulated by DEX 6 and 24 h post operation. The norepinephrine and cortisol levels in serum were downregulated by DEX 15 and 30 min post operation. The interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) levels in serum were also downregulated by DEX 15 and 30 min post operation. DEX alleviated POCD and inflammation in elderly patients who underwent intubation.

Perioperative Acupuncture Optimizes Surgical Outcomes: Theory, Clinical Practice and Future Perspectives

A growing body of evidence supports the use of perioperative acupuncture as part of an enhanced postsurgical recovery protocol. Data from both clinical trials and animal studies has shown that the integration of acupuncture into perioperative patient care leads to a reduction of perioperative complications such as preoperative anxiety, intraoperative hemodynamic instability, postoperative pain, postoperative cognitive dysfunction, and postoperative nausea and vomiting in surgical patients. Despite these favorable outcomes, perioperative acupuncture has yet to be widely adopted in current anesthesia practice. This review summarized data from clinical perioperative acupuncture studies and cites recent discoveries regarding the anatomical location and characteristics of acupoint(s), acupuncture stimulation techniques, and treatment practice protocols, as well as identified the areas of deficiency in perioperative acupuncture applications. To facilitate acupuncture integration in perioperative care practice, the authors propose to establish a perioperative acupuncture registry which can be used for data mining as well as a resource for studying the underlying mechanisms of acupuncture. Through this acupuncture registry, clinical guidelines and research protocols can be established, additional large/multi-center clinical and pragmatic trials can be easily performed to determine if the integration and expansion of perioperative acupuncture practice is cost-effective.

Transcutaneous Electrical Acupoint Stimulation Combined With Auricular Acupressure Reduces Postoperative Delirium Among Elderly Patients Following Major Abdominal Surgery: A Randomized Clinical Trial

Background

Postoperative delirium is common in elderly patients following major surgery. This study aimed to assess the effect of transcutaneous electrical acupoint stimulation combined with auricular acupressure on the incidence of postoperative delirium among older patients undergoing major abdominal surgery.

Methods

In this single-center, randomized controlled clinical trial, 210 patients aged 65 years or older undergoing major abdominal surgery were randomized to receive either intervention treatment (transcutaneous electrical acupoint stimulation started at 30 min before anesthesia until the end of the surgery, followed by intermittent auricular acupressure in the first three postoperative days; n = 105) or standard care (n = 105). The primary outcome was the incidence of delirium at the first seven postoperative days or until hospitalization depended on which came first. Secondary outcomes included delirium severity, opioid consumption, postoperative pain score, sleep quality, length of postoperative hospital stay, and postoperative 30-day complications. Enrollment was from April 2019 to March 2020, with follow-up ending in April 2020.

Results

All of the 210 randomized patients [median age, 69.5 years, 142 (67.6%) male] completed the trial. The incidence of postoperative delirium was significantly reduced in patients received intervention treatment (19/105 (18.1%) vs. 8/105 (7.6%), difference, –10.5% [95% CI, –1.5% to –19.4%]; hazard ratio, 0.41 [95% CI, 0.18 to 0.95]; P= 0.023). Patients in the control group had a higher postoperative Memorial Delirium Assessment Scale (4 vs. 3; difference, –1; 95% CI, –1 to 0; P = 0.014) and a greater increase in Pittsburgh Sleep Quality Index score from baseline to postoperative day three (2.5 vs. 2.0; difference, –1; 95% CI, –2 to –1; P &lt; 0.001) than patients in the intervention group. No significant difference was observed as of other secondary outcomes.

Conclusion

In elderly patients undergoing major abdominal surgery, transcutaneous electrical acupoint stimulation combined with auricular acupressure reduced the incidence of postoperative in-hospital delirium compared with standard care. A multicenter, randomized clinical trial with a larger sample size is necessary to verify these findings.

Clinical Trial Registration

[https://clinicaltrials.gov], identifier [NCT03726073].

Neuroinflammation as the Underlying Mechanism of Postoperative Cognitive Dysfunction and Therapeutic Strategies

Postoperative cognitive dysfunction (POCD) is a common neurological complication following surgery and general anesthesia, especially in elderly patients. Severe cases delay patient discharge, affect the patient’s quality of life after surgery, and are heavy burdens to society. In addition, as the population ages, surgery is increasingly used for older patients and those with higher prevalences of complications. This trend presents a huge challenge to the current healthcare system. Although studies on POCD are ongoing, the underlying pathogenesis is still unclear due to conflicting results and lack of evidence. According to existing studies, the occurrence and development of POCD are related to multiple factors. Among them, the pathogenesis of neuroinflammation in POCD has become a focus of research in recent years, and many clinical and preclinical studies have confirmed the correlation between neuroinflammation and POCD. In this article, we reviewed how central nervous system inflammation occurred, and how it could lead to POCD with changes in peripheral circulation and the pathological pathways between peripheral circulation and the central nervous system (CNS). Furthermore, we proposed some potential therapeutic targets, diagnosis and treatment strategies at the cellular and molecular levels, and clinical applications. The goal of this article was to provide a better perspective for understanding the occurrence of POCD, its development, and preventive strategies to help manage these vulnerable geriatric patients.

Propofol alleviates postoperative cognitive dysfunction by inhibiting inflammation via up-regulating miR-223-3p in aged rats

OBJECTIVE

Postoperative cognitive dysfunction (POCD) affects 15-25% of surgical patients and causes significant morbidity and mortality. This study aims to investigate the mechanism of propofol reducing POCD in aged rats.

METHOD

Rats in Operate group and Propofol group were anesthetized with isoflurane and propofol, respectively, and then underwent cardiac surgery. Rats in Antagomir group were anesthetized with propofol and underwent cardiac surgery with preoperative injection of miR-223-3p antagomir. Barnes maze and Morris water maze (MWM) were used to test spatial learning and memory of rats. Immunofluorescence was used to detect the level of microglial cell marker IBA1. In addition, qRT-PCR was performed to measure the expression of miR-223-3p and inflammatory factors TNF-α, IL-1β and IL-6. Western blotting was conducted to detect the protein expression of Foxo1, TNF-α, IL-1β and IL-6.

RESULT

Isoflurane-anesthetized rats undergoing cardiac surgery showed significantly reduced spatial learning and memory, promoted microglia activation, decreased miR-223-3p expression and increased inflammatory response in the hippocampus, while isoflurane-anesthetized rats without surgery showed insignificant changes in these indices. Compared to isoflurane anesthesia, propofol anesthesia exhibited less effect on spatial learning and memory of rats with cardiac surgery and contributed to a relative reduction in activated microglia in the hippocampus, a notable increase in miR-223-3p expression, and a decrease in inflammation. The results were reversed after miR-223-3p antagomir was injected into propofol-anesthetized surgical rats. miR-223-3p negatively regulated Foxo1 to suppress the expression of inflammatory factors.

CONCLUSION

Propofol reduced inflammation by up-regulating miR-223-3p, thereby reducing POCD in aged rats.

The effect of dexmedetomidine combined with epidural anesthesia on post-operative cognitive dysfunction in elderly patients after orthopedic surgery

OBJECTIVE

To investigate the effect of dexmedetomidine combined with epidural anesthesia on cognitive dysfunction (POCD) in elderly patients after orthopedic surgery.

METHODS

A total of 187 elderly patients who needed orthopedic surgery in our hospital from January 2019 to December 2020 were randomly divided into an experimental group (n=95) and a control group (n=92). The patients in the experimental group were administered 1 μg/kg dexmedetomidine hydrochloride injections, and the patients in the control group were administered 0.9% sodium chloride injections, which were infused using a micropump for about 10 minutes. The two groups' cognitive function, VAS scores, and vital signs were compared.

RESULTS

There were significant differences in the two groups' mean arterial pressures and heart rates at intubation time (T3), operation start time (T4), and extubation time (T6) (P < 0.05). The VAS scores in the experimental group were significantly different from the VAS scores in the control group at 24 hours after the operations, 48 hours after the operations, 72 hours after the operations, and 7 days after the operations (P < 0.05). There were no significant differences in the anesthesia times, the average bleeding volumes, or the average operative durations (P > 0.05). 48 hours after the operations, the MMSE score in the experimental group was (27.15±1.17), which was significantly different than the MMSE score in the control group (23.11±0.83), and the difference was statistically significant (P < 0.05).

CONCLUSION

Epidural anesthesia combined with dexmedetomidine has little circulatory interference in elderly patients; moreover, it can reduce the incidence of postoperative cognitive dysfunction in elderly patients.

Update on the Mechanism and Treatment of Sevoflurane-Induced Postoperative Cognitive Dysfunction

Sevoflurane is one of the most widely used anesthetics for the induction and maintenance of general anesthesia in surgical patients. Sevoflurane treatment may increase the incidence of postoperative cognitive dysfunction (POCD), and patients with POCD exhibit lower cognitive abilities than before the operation. POCD affects the lives of patients and places an additional burden on patients and their families. Understanding the mechanism of sevoflurane-induced POCD may improve prevention and treatment of POCD. In this paper, we review the diagnosis of POCD, introduce animal models of POCD in clinical research, analyze the possible mechanisms of sevoflurane-induced POCD, and summarize advances in treatment for this condition.

Effects of Transcutaneous Electrical Acupoint Stimulation on Postoperative Cognitive Decline in Elderly Patients: A Pilot Study

Background

Postoperative cognitive decline (POCD) in the old ages seriously delays the rapid recovery. Here, we aimed to investigate the effects of transcutaneous electrical acupoint stimulation (TEAS) against POCD in elderly patients undergoing laparoscopic radical colon cancer surgery, as well as the potential mechanism.

Methods

A prospective, single-center, parallel-group, randomized trial was designed. A total of 100 patients (age ≥65 years) undergoing laparoscopic radical resection of colon cancer were involved and randomly divided into TEAS (Group T) and control (Group C) groups. The patients in Group T were performed with percutaneous acupoint electrical stimulation in bilateral Hegu, Neiguan and Zusanli points from 30 minutes before anesthesia induction to the end of surgery. A Z-score based on Mini-Mental State Exam (MMSE) was used to assess the incidence of POCD. The levels of serum IL-6, hs-CRP, CGRP at 0 min before TEAS (T0), 1 h after beginning of surgery (T1) and the end of surgery (T2) were evaluated.

Results

Our data showed that the cumulative duration of POCD on postoperative day 2 and 3 in Group T was significantly decreased compared to Group C (P < 0.05). Compared with T0, the levels of serum IL-6, hs-CRP, and CGRP in both Group T and C were statistically elevated at T1 and T2 (P < 0.05). Moreover, the levels of serum IL-6 and hs-CRP were decreased, but the level of CGRP was increased in Group T compared to Group C at T1 and T2 (P < 0.05).

Conclusion

TEAS is associated with a lower cumulative duration of POCD in elderly patients undergoing laparoscopic radical colon cancer surgery, which may be related to the regulation of inflammatory factors and neuropeptides interacted with gut–brain axis.

Acupuncture for postoperative delirium (POD): A systematic review and meta-analysis protocol

BACKGROUND

Postoperative delirium (POD) is a form of delirium that is newly diagnosed after a surgical procedure. This study aims to examine the effectiveness and safety of acupuncture treatment for POD in patients who underwent surgery.

METHODS

Randomized controlled trials for patients diagnosed with POD using validated delirium assessment scales will be included in this review. Electronic databases, such as MEDLINE, EMBASE, CENTRAL, CINAHL (English DB), CNKI, Wanfang, VIP (Chinese database), KoreaMed, RISS, KISS, DBpia, OASIS (Korean DB), and J-STAGE (Japanese DB) will be searched without language limitation from their inception to October 2020. The intervention group will include patients who have received any type of acupuncture treatment for POD. The control group will include individuals with no treatment, sham acupuncture treatment, and conventional treatment. The primary outcome is the incidence of POD in each study. Quality assessment will be performed using the Cochrane risk of bias tool. A meta-analysis will be performed to pool the estimated effect.

CONCLUSION

This study will provide evidence for acupuncture as a potential treatment for POD, in researchers, patients, and policy makers.

DISSEMINATION

The result of the study will be disseminated through posters, press releases, conference presentations, and peer-reviewed papers.

TRIAL REGISTRATION NUMBER

OSF 2020: (https://osf.io/usvdg).

Dexmedetomidine Alleviates LPS-Induced Neuronal Dysfunction by Modulating the AKT/GSK-3β/CRMP-2 Pathway in Hippocampal Neurons

OBJECTIVE

Dexmedetomidine, an α2-adrenergic receptor agonist, mitigates cognitive dysfunction in elderly patients after surgery with general anesthesia. However, the underlying mechanism by which dexmedetomidine reduces cognitive dysfunction remains to be fully elucidated. The aim of this study was to investigate the effects of dexmedetomidine on lipopolysaccharide (LPS)-induced neuronal dysfunction in cultured hippocampal neurons.

METHODS

LPS, in the presence and absence of dexmedetomidine, was applied to cultured hippocampal neurons to mimic post-surgical inflammation. Neuronal morphology, including neurite outgrowth and synaptic transmission, was observed, and miniature excitatory postsynaptic currents were recorded by electrophysiological patch-clamp.

RESULTS

LPS significantly impaired neurite outgrowth in hippocampal neurons in a concentration- and time-dependent manner, which was reversed by dexmedetomidine treatment. Electrophysiological patch-clamp results showed that LPS induced synaptic transmission dysfunction, which was restored after dexmedetomidine addition. Furthermore, Western blotting assays showed that LPS suppressed the AKT/GSK-3β/CRMP-2 signaling pathway and dexmedetomidine countered the inhibitory effect of LPS by re-activating this pathway.

CONCLUSION

In general, dexmedetomidine protected against the effects of LPS-induced hippocampal neuron damage, including neurite outgrowth and synaptic transmission. Overall, dexmedetomidine modulated the AKT/GSK-3β/CRMP-2 signaling pathway to alleviate LPS-induced neurological dysfunction.