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SYSTEMATIC REVIEW article

Front. Med., 15 January 2026

Sec. Intensive Care Medicine and Anesthesiology

Volume 13 - 2026 | https://doi.org/10.3389/fmed.2026.1717702

Transcutaneous electrical acupoint stimulation for preventing postoperative delirium in elderly patients: a systematic review and meta-analysis

Yi-jiao ChenYi-jiao Chen1Qi-hong ShenQi-hong Shen2Yi YangYi Yang3Rui ShenRui Shen3Hui-fang Li
Hui-fang Li3*
  • 1Department of Anesthesiology, Sir Run Run Shaw Hospital Affiliated with the Zhejiang University School of Medicine, Hangzhou, China
  • 2Department of Anesthesiology, Affiliated Hospital of Jiaxing University, Jiaxing, China
  • 3Department of TCM, Tongxiang Maternal and Child Health-Care Center, Tongxiang, Zhejiang, China

Objective: To systematically evaluate the efficacy of transcutaneous electrical acupoint stimulation (TEAS) in preventing postoperative delirium (POD) in elderly patients undergoing various surgical procedures.

Methods: A comprehensive literature search was conducted across multiple electronic databases to identify randomized controlled trials (RCTs) comparing TEAS with control interventions (sham or no stimulation) in patients aged >60 years undergoing surgery. The primary outcome was the incidence of POD within the first seven postoperative days. Meta-analysis was performed using RevMan software, calculating risk ratios (RR), mean differences (MD), or standard MD with 95% confidence intervals (CIs). The quality of evidence was assessed based on the Grading of Recommendations Assessment, Development, and Evaluation approach.

Results: Twenty RCTs involving 2,290 patients (aged >60 years) were included. The overall incidence of POD was 5.6% in the TEAS group compared to 17.0% in the control group (RR 0.34, 95% CI 0.26–0.45). TEAS also significantly reduced CAM score (MD −1.01, 95% CI −1.98 to −0.04), propofol consumption (MD −35.59 mg, 95% CI −65.75 to −5.42), postoperative pain score (MD −0.60, 95% CI −1.02 to −0.18), and improved recovery quality (QoR-15 score: MD 23.76, 95% CI 21.72–25.80). The intervention appeared safe with no serious adverse events reported.

Conclusion: Perioperative TEAS application significantly reduces the risk of POD in elderly surgical patients. Its protective effects are potentially mediated through anti-inflammatory effects. TEAS represents a promising non-pharmacological intervention for POD prevention within enhanced recovery protocols.

Systematic review registration: CRD420251128976.

Introduction

Postoperative delirium (POD) constitutes a prevalent and serious complication in elderly surgical patients, characterized by acute fluctuations in attention, awareness, and cognition (1, 2). Its incidence varies considerably, ranging from 15 to 50% depending on the type of surgery and patient vulnerability, and it is associated with devastating consequences, including prolonged hospitalization, increased healthcare costs, accelerated cognitive decline, higher morbidity and mortality rates, and elevated caregiver burden (3, 4). The aging global population has led to a rising number of elderly patients undergoing surgical interventions, making POD a critical public health concern that imperatively demands effective preventive strategies.

The pathophysiology of POD is multifactorial and not entirely elucidated, but it is widely recognized as a manifestation of cerebral vulnerability precipitated by the stress response to surgery and anesthesia (5). Key mechanistic contributors include neuroinflammation (6), increased permeability of the blood–brain barrier (7), oxidative stress (8), and neuronal injury (9). Current preventive approaches are primarily pharmacological, often involving antipsychotics or other psychoactive medications; however, their efficacy remains limited and their use is frequently associated with significant adverse effects, including sedation, and cardiovascular events (10, 11). This limited risk–benefit profile underscores the urgent need for safe, effective, and non-pharmacological adjunctive interventions.

Transcutaneous electrical acupoint stimulation (TEAS), a non-invasive modality derived from traditional acupuncture principles, applies electrical stimulation to specific acupoints through surface electrodes (12). It has gained increasing attention in perioperative medicine for its potential to modulate physiological functions, including analgesia, anti-emesis, attenuation of the surgical stress response, and organ protection (1316). Emerging evidence from randomized controlled trials (RCTs) suggests that TEAS may confer protective effects against POD by modulating inflammatory cytokines (17), reducing markers of neuronal injury (18), improving sleep quality (19), and decreasing analgesic requirements (20). However, the findings across individual studies have been inconsistent, and the overall efficacy of TEAS for POD prevention has not been conclusively established due to variations in study design, patient populations, and TEAS protocols.

Therefore, we conducted this systematic review and meta-analysis of RCTs to synthesize the existing evidence and quantitatively evaluate the efficacy of TEAS in preventing POD in elderly patients undergoing surgery. We aimed to evaluate its effect on POD incidence and explore its impact on secondary outcomes including cognitive scores, pain, recovery quality, and key pathophysiological biomarkers.

Methods

This systematic review and meta-analysis was conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The study protocol was registered prospectively on the International Prospective Register of Systematic Reviews (PROSPERO) (Registration number: CRD420251128976).

Search strategy and data sources

A comprehensive and systematic literature search was performed from inception until July 31, 2025 to identify all relevant published RCTs. The following electronic databases were searched: PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang Data, and VIP Database. The full detailed search strategy, including all MeSH terms and free-text keywords used for each database, is provided in Supplementary material. In brief, the search concepts included terms related to the intervention (“transcutaneous electrical acupoint stimulation,” “TEAS,” “acupoint”) and the outcome (“postoperative delirium,” “POD,” “delirium”) combined with filters for RCTs and aged population. No language restrictions were applied. The reference lists of all included studies and relevant review articles were also manually screened to identify any additional eligible records.

Eligibility criteria

Studies were selected based on the following PICOS criteria: Population (P): Patients aged ≥60 years undergoing any elective surgical procedure. Intervention (I): Perioperative TEAS applied alone or as an adjunct to standard anesthesia care. Studies using any acupoint selection [e.g., Shenmen (HT7), Neiguan (PC6), Hegu (LI4)] and stimulation parameters were included. Comparison (C): Sham TEAS (electrodes placed at the same acupoints without electrical stimulation) or standard care/placebo. Outcomes (O): The primary outcome was the incidence of POD within the first seven postoperative days, diagnosed using validated tools such as the Confusion Assessment Method (CAM) or its variants. Secondary outcomes included CAM score, intraoperative propofol and remifentanil consumption, postoperative pain score, quality of recovery (QoR-15 score), levels of neuronal injury markers (TNF-α and NSE), and other adverse events (e.g., postoperative nausea and vomiting, PONV). Study Design (S): Only RCTs were included.

Study selection and data extraction

Two reviewers independently screened titles, abstracts, and subsequently full-text articles according to the eligibility criteria. Any discrepancies were resolved through discussion or by consultation with a third reviewer. A standardized pre-piloted data extraction form was used to collect information on: first author, publication year, sample size, patient characteristics, surgical type, TEAS protocol (acupoints, parameters, timing), control intervention, and outcomes of interest.

Risk of bias and quality assessment

The methodological quality of the included studies was assessed using the Cochrane Risk of Bias tool by two independent reviewers. The assessment covered domains of random sequence generation, allocation concealment, blinding of participants and personnel, blinding of outcome assessment, incomplete outcome data, selective reporting, and other potential biases. The overall certainty of evidence for each outcome was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach.

Data synthesis and statistical analysis

Statistical analysis was performed using Review Manager (RevMan) software (Version 5.4, The Cochrane Collaboration) and Stata software (Version 17.0). For dichotomous outcomes (e.g., POD incidence), the treatment effect was expressed as risk ratios (RR) with 95% confidence intervals (CIs). For continuous outcomes (e.g., pain score, biomarker levels), mean difference (MD) or standardized MD (SMD) were calculated with 95% CIs. Heterogeneity among studies was assessed using the I2 statistic and Chi-squared test. An I2 value > 50% indicated substantial heterogeneity. Considering multiple factors that contributed to the high clinical heterogeneity in this study, a random-effect model was utilized for the studies with low I2 values. Pre- specified subgroup analyses were conducted based on surgical type to explore potential sources of heterogeneity. Sensitivity analyses were performed to test the robustness of the results. Publication bias was assessed visually using funnel plots.

Results

Study selection

The initial systematic literature search identified a total of 391 records from all electronic databases and other sources. After removing duplicates, 178 unique records remained for title and abstract screening. Following this initial screening, 22 articles were selected for full-text review to assess their eligibility against the pre-defined PICOS criteria. After a detailed evaluation, 20 RCTs met all inclusion criteria and were included in the quantitative synthesis (meta-analysis) (1736). The detailed process of study selection, with reasons for exclusion at the full-text stage, is presented in the PRISMA flow diagram (Figure 1).

Figure 1
Flowchart of a systematic review process. Identification: 391 records from databases, none from registers. 213 duplicates removed, none marked ineligible or removed for other reasons. Screening: 178 records screened, 156 excluded. 22 reports sought, none not retrieved. Eligibility: 22 assessed, 2 excluded for being conference abstracts or combined. Inclusion: 20 studies included in review.

Figure 1. PRISMA flow diagram.

Study characteristics

The 20 included studies enrolled a total of 2,290 patients, with sample sizes ranging from 57 to 547 participants. All studies involved elderly patients (age >60 years) undergoing various surgical procedures, including but not limited to hip fracture repair, laparoscopic cholecystectomy, radical thyroidectomy, and spinal open surgery. The baseline characteristics of included studies is shown in Table 1. The TEAS interventions utilized common acupoints, predominantly Shenmen (HT7), Neiguan (PC6), Hegu (LI4), and Zusanli (ST36). Stimulation parameters varied across studies, with frequencies often set at 2/100 Hz (dense-disperse mode) and intensity adjusted to patient tolerance (typically 6–15 mA). The control groups received either sham TEAS (placebo stimulation) or standard care. The primary outcome (POD incidence) was assessed using the CAM or its variants in all studies. A detailed summary of the characteristics of the included studies is provided in Table 2.

Table 1
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Table 1. Baseline characteristics of included studies.

Table 2
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Table 2. A detailed summary of the characteristics of the included studies.

Risk of bias assessment

The methodological quality of the included studies was assessed using the Cochrane Risk of Bias tool. Allocation concealment was clearly reported in only three trials. Blinding of participants and personnel was implemented in four trials. Five trials reported blinding of outcome assessment. Two studies had the risk of selective reporting. A visual summary of the risk of bias across all domains is presented in Figure 2.

Figure 2
Risk of bias summary table for various studies from 2018 to 2025. It includes categories like random sequence generation, allocation concealment, and others. Green plus signs indicate low risk, yellow question marks signify unclear risk, and red minus signs denote high risk.

Figure 2. The risk bias assessment of all included studies.

Results of meta-analysis

Primary outcome: incidence of POD

Nineteen studies reported data on the incidence of POD. The pooled meta-analysis using a random-effects model demonstrated that TEAS significantly reduced the risk of developing POD compared to the control group. The overall effect was highly statistically significant (RR = 0.34, 95% CI: 0.26–0.45; p < 0.001, I2 = 0%). The forest plot for the primary outcome is shown in Figure 3.

Figure 3
Forest plot showing the risk ratios of various studies comparing TEAS and control groups, with confidence intervals. Each study's result is represented with a blue square, indicating the risk ratio, and horizontal lines showing confidence intervals. The diamond at the bottom represents the overall effect size. Heterogeneity statistics are included, showing a lack of heterogeneity among studies. Risk ratios less than one favor the experimental group.

Figure 3. Forest plot of the incidence of POD between TEAS and control group (POD, postoperative delirium; TEAS, transcutaneous electrical acupoint stimulation).

Secondary outcomes

CAM Score: Pooled analysis from four studies that reported CAM score showed that patients in the TEAS group had significantly lower score than those in the control group (MD = −1.01, 95% CI: −1.98 to −0.04; p < 0.05, I2 = 80%) (Figure 4), indicating less severe delirium symptoms.

Figure 4
Forest plot depicting the mean differences in effects between TEAS and control groups across four studies. Mean differences range from -2.01 to -0.20, with an overall effect of -1.01. Confidence intervals vary, with heterogeneity indicated by Tau-squared equals 0.76 and I-squared equals 80 percent. The plot shows forest markers indicating the variance of each study, with a diamond representing the overall effect favoring the experimental group.

Figure 4. Forest plot of the CAM score between TEAS and control group (CAM, Confusion Assessment Method; TEAS, transcutaneous electrical acupoint stimulation).

Postoperative Pain Score: Meta-analysis of five studies assessing pain intensity revealed that TEAS was associated with a statistically significant reduction in postoperative pain score compared to control (MD = −0.60, 95% CI: −1.02 to −0.18; p < 0.05, I2 = 86%) (Figure 5).

Figure 5
Forest plot comparing TEAS and control groups across five studies. Studies show mean differences with confidence intervals on a scale ranging from -4 to 4, favoring either experimental or control groups. Overall mean difference is -0.60, with significant heterogeneity (I² = 86%). The plot's summary diamond indicates overall effect.

Figure 5. Forest plot of the postoperative pain score between TEAS and control group (TEAS, transcutaneous electrical acupoint stimulation).

Quality of Recovery: Data from two studies using the QoR-15 indicated that the TEAS group experienced a significantly better quality of recovery in the postoperative period (MD = 23.76, 95% CI: 21.72–25.80; p < 0.05, I2 = 0%) (Figure 6).

Figure 6
Forest plot displaying meta-analysis results comparing TEAS versus control. Studies include Du 2022 and Liu 2019, with mean differences favoring TEAS. Total heterogeneity is low with Tau-squared and I-squared both at zero. Overall effect test shows significant favor towards the experimental group, with Z-score of 22.80 and p-value less than 0.00001.

Figure 6. Forest plot of the QoR-15 score between TEAS and control group (TEAS, transcutaneous electrical acupoint stimulation).

Inflammatory and Neuronal Injury Biomarkers: Qualitative synthesis suggested a consistent trend across studies where TEAS was associated with lower postoperative levels of neuronal injury markers (TNF-α and NSE) (Supplementary Figures 1, 2) compared to control groups.

Intraoperative propofol and remifentanil consumption: The pooled analysis showed a significant reduction in propofol consumption the TEAS group compared to control (MD −35.59 mg, 95% CI −65.75 to −5.42, p < 0.05) (Figure 7), while no significant difference in remifentanil consumption (SMD −0.66, 95% CI −1.60–0.27, p > 0.05) (Figure 8).

Figure 7
Forest plot comparing TEAS and control groups across four studies with mean differences and 95% confidence intervals. Studies include Wang 2022, Wei 2022, Wu 2021, and Xu 2022. The overall effect shows a mean difference of -35.59, favoring the experimental group. Heterogeneity is high with I² at 84%.

Figure 7. Forest plot of propofol consumption between TEAS and control group (TEAS, transcutaneous electrical acupoint stimulation).

Figure 8
Forest plot showing the standardized mean difference in TEAS versus control across four studies. Studies include Wang 2022, Wei 2022, Wu 2021, and Xu 2022. The plot indicates individual study effects with confidence intervals, and a total effect size of -0.66 with a 95% confidence interval of -1.60 to 0.27. Heterogeneity is high (I² = 94%), and the overall effect test is not significant (p = 0.16).

Figure 8. Forest plot of remifentanil consumption between TEAS and control group (TEAS, transcutaneous electrical acupoint stimulation).

Adverse Events: Meta-analysis revealed that no statistically significant difference in incidence of PONV, hypotension and bradycardia between two groups (Supplementary Figures 3–5).

Subgroup and sensitivity analyses

Pre-specified subgroup analyses based on surgical type (orthopedic surgeries vs. non-orthopedic surgeries) (Supplementary Figure 6) did not identify significant subgroup differences, suggesting a consistent benefit of TEAS across these categories. Sensitivity analyses, performed by excluding each study, did not materially alter the overall pooled estimate for the primary outcome, confirming the robustness of the results.

Publication bias

Publication bias was assessed for the primary outcome (incidence of POD) through visual inspection of the funnel plot. The funnel plot displayed an approximately symmetrical distribution of effect estimates around the pooled result (Figure 9). Based on this visual assessment, there was no obvious evidence of significant publication bias among the included studies for this outcome.

Figure 9
Funnel plot displaying several circles representing studies, distributed around a vertical dashed line. The x-axis is labeled

Figure 9. Funnel plot for the primary outcome.

Certainty of evidence (GRADE)

According to the GRADE approach, the certainty of evidence for the primary outcome (POD incidence) was assessed as moderate. The rating “Other considerations” was downgraded “serious.” The certainty of evidence for other outcomes was ranged from low to moderate. Table 3 showed the summary of GRADE.

Table 3
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Table 3. Summary for GRADE assessment.

Discussion

This systematic review and meta-analysis of 20 randomized controlled trials, encompassing 2,290 elderly surgical patients, provides evidence that perioperative TEAS is associated with a significantly reduced risk of POD. Furthermore, our analysis demonstrates that TEAS confers additional benefits, including amelioration of delirium severity, reduction in postoperative pain, and improvement in the overall quality of recovery. The intervention was found to be safe, with no serious adverse events reported.

The magnitude of the protective effect observed in our study is substantial and underscores the potential of TEAS as a pivotal non-pharmacological strategy within enhanced recovery after surgery (ERAS) protocols (37). The consistency of the beneficial effect across diverse surgical populations, as confirmed by our subgroup analysis showing no significant difference between orthopedic and non-orthopedic surgeries, enhances the generalizability of our findings. This suggests that the neuroprotective mechanism of TEAS may target fundamental pathways common to the pathogenesis of delirium following various surgical insults.

The positive effects of TEAS on secondary outcomes offer critical insights into its potential mechanisms of action. The significant reduction in CAM scores indicates that TEAS not only prevents the onset of delirium but also mitigates its severity. The observed analgesic effect is particularly salient. Postoperative pain is a well- established risk factor for POD; it induces stress, disrupts sleep, and often necessitates increased opioid consumption, which itself can contribute to neuroinflammation and cognitive dysfunction (38, 39). By effectively reducing pain, TEAS may break this vicious cycle, thereby reducing the delirium burden. This is further supported by the marked improvement in the QoR-15 score, indicating a holistic enhancement of the patient’s postoperative experience.

While the exact mechanisms remain to be fully elucidated, our results, combined with the findings of the included studies, point toward multi-modal actions. The qualitative synthesis suggesting a reduction in inflammatory (TNF-α) and neuronal injury (NSE) biomarkers aligns with the prevailing neuroinflammatory hypothesis of POD. Surgery triggers a systemic inflammatory response, leading to the release of cytokines that can breach the blood–brain barrier, activate microglia, and disrupt neuronal function and neurotransmission. TEAS has been shown in preclinical and clinical studies to modulate this response, potentially through vagal nerve stimulation and cholinergic anti-inflammatory pathways, leading to a attenuated neuroinflammatory state (40, 41). The underlying pathway may involve the modulation of the cholinergic anti-inflammatory pathway via vagal nerve activation, which suppresses the release of pro-inflammatory cytokines such as TNF-α (42). This anti-inflammatory effect, coupled with improved analgesia and sleep quality, likely creates a synergistic effect that protects the vulnerable aging brain from the precipitating factors of delirium.

Our analysis further indicated that TEAS reduced intraoperative propofol requirement while exerting no significant effect on remifentanil consumption. The propofol-sparing effect is clinically meaningful, as propofol may contribute to neuroinflammation in the aging brain (43). TEAS likely provides intrinsic sedation through GABAergic modulation (44), thereby lowering propofol demand and its potential neurotoxic burden.

Several limitations of this analysis must be acknowledged. First, the overall certainty of evidence was graded as moderate for the primary outcome, primarily due to the methodological limitations present in many of the included studies. Common issues included unclear allocation concealment and challenges in blinding personnel administering the intervention, which are inherent difficulties in trials of physical interventions like TEAS. While sham TEAS was employed as control in most studies, the inability to blind personnel may have introduced performance bias. Second, while the funnel plot appeared symmetrical, the possibility of unpublished negative studies (publication bias) can never be completely excluded. Third, we observed substantial statistical heterogeneity (I2 > 80%) in the meta-analyses for CAM scores and postoperative pain score. This heterogeneity likely stems from clinical diversity, including variations in the specific TEAS protocols (acupoint combinations, stimulation parameters, treatment duration), the types and intensities of surgical procedures, and the different tools used to assess pain. While the random-effects model accounts for this, the findings should be interpreted with awareness of this underlying variability. Fourth, an important clinical dimension of POD, its psychomotor subtype (hyperactive, hypoactive, mixed), could not be analyzed. None of the included studies reported such data. Finally, the majority of included trials were conducted in China, which may limit the generalizability of our findings to other healthcare settings and ethnic populations. Future international multi-center studies are warranted.

Conclusion

In conclusion, this meta-analysis provides evidence that perioperative TEAS is an effective and safe intervention for preventing postoperative delirium in elderly patients. Its benefits extend beyond mere risk reduction to encompass less severe delirium, improved pain control, and a better overall recovery experience. TEAS might be considered a promising component of multimodal, non-pharmacological strategies aimed at optimizing neurological outcomes and enhancing recovery in the growing population of elderly surgical patients.

Data availability statement

The original contributions presented in the study are included in the article/Supplementary material, further inquiries can be directed to the corresponding author.

Author contributions

Y-jC: Conceptualization, Writing – original draft, Writing – review & editing. Q-hS: Conceptualization, Data curation, Writing – review & editing. YY: Investigation, Methodology, Writing – review & editing. RS: Investigation, Methodology, Writing – original draft. H-fL: Conceptualization, Software, Writing – original draft, Writing – review & editing.

Funding

The author(s) declared that financial support was not received for this work and/or its publication.

Conflict of interest

The author(s) declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Generative AI statement

The author(s) declared that Generative AI was not used in the creation of this manuscript.

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Supplementary material

The Supplementary material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fmed.2026.1717702/full#supplementary-material

References

1. Li, T, Li, J, Yuan, L, Wu, J, Jiang, C, Daniels, J, et al. Effect of regional vs. general anesthesia on incidence of postoperative delirium in older patients undergoing hip fracture surgery: the RAGA randomized trial. JAMA. (2022) 327:50–8. doi: 10.1001/jama.2021.22647,

PubMed Abstract | Crossref Full Text | Google Scholar

2. Aldecoa, C, Bettelli, G, Bilotta, F, Sanders, RD, Aceto, P, Audisio, R, et al. Update of the european society of anaesthesiology and intensive care medicine evidence-based and consensus-based guideline on postoperative delirium in adult patients. Eur J Anaesthesiol. (2024) 41:81–108. doi: 10.1097/EJA.000000000000187

Crossref Full Text | Google Scholar

3. Jin, Z, Hu, J, and Ma, D. Postoperative delirium: perioperative assessment, risk reduction, and management. Br J Anaesth. (2020) 125:492–504. doi: 10.1016/j.bja.2020.06.063,

PubMed Abstract | Crossref Full Text | Google Scholar

4. Li, J, Fan, Y, Luo, R, Yin, N, Wang, Y, Jing, J, et al. The impact of non-pharmacological sleep interventions on delirium prevention and sleep improvement in postoperative ICU patients: a systematic review and network meta-analysis. Intensive Crit Care Nurs. (2025) 87:103925. doi: 10.1016/j.iccn.2024.103925,

PubMed Abstract | Crossref Full Text | Google Scholar

5. Tong, RJ, Lv, YZ, Shi, YF, Lai, L, and Shen, QH. Remimazolam versus propofol for postoperative delirium prevention in geriatric surgery: a systematic review and meta-analysis of randomized controlled trials. Aging Clin Exp Res. (2025) 37:253. doi: 10.1007/s40520-025-03166-6,

PubMed Abstract | Crossref Full Text | Google Scholar

6. Feng, H, Liu, Y, Wang, X, Wang, C, and Wang, T. Cerebrospinal fluid biomarkers of neuroinflammation and postoperative neurocognitive disorders in patients undergoing orthopedic surgery: a systematic review and meta-analysis. Int J Surg. (2025) 111:3573–88. doi: 10.1097/JS9.0000000000002344,

PubMed Abstract | Crossref Full Text | Google Scholar

7. Taylor, J, Parker, M, Casey, CP, Tanabe, S, Kunkel, D, Rivera, C, et al. Postoperative delirium and changes in the blood-brain barrier, neuroinflammation, and cerebrospinal fluid lactate: a prospective cohort study. Br J Anaesth. (2022) 129:219–30. doi: 10.1016/j.bja.2022.01.005,

PubMed Abstract | Crossref Full Text | Google Scholar

8. Lopez, MG, Shotwell, MS, Hennessy, C, Pretorius, M, McIlroy, D, Kimlinger, MJ, et al. Intraoperative oxygen treatment, oxidative stress, and organ injury following cardiac surgery: a randomized clinical trial. JAMA Surg. (2024) 159:1106–16. doi: 10.1001/jamasurg.2024.2906,

PubMed Abstract | Crossref Full Text | Google Scholar

9. Skelly, DT, Griffin, ÉW, Murray, CL, Harney, S, O'Boyle, C, Hennessy, E, et al. Acute transient cognitive dysfunction and acute brain injury induced by systemic inflammation occur by dissociable IL-1-dependent mechanisms. Mol Psychiatry. (2019) 24:1533–48. doi: 10.1038/s41380-018-0075-8,

PubMed Abstract | Crossref Full Text | Google Scholar

10. Queiroz, I, Barbosa, LM, Gallo Ruelas, M, Araújo, B, Defante, MLR, Tavares, AH, et al. Effect of peri-operative pharmacological interventions on postoperative delirium in patients having cardiac surgery: a systematic review and Bayesian network meta-analysis. Anaesthesia. (2025). [Epub ahead of print]. doi: 10.1111/anae.16757

Crossref Full Text | Google Scholar

11. Caetano da Silva, L, Tapioca, V, Viana, P, Pereira, EM, Gibicoski, T, and Amaral, S. Dexmedetomidine for delirium prevention after cardiac surgery: an updated systematic review and meta-analysis with trial sequential analysis. Anaesth Crit Care Pain Med. (2025) 44:101578. doi: 10.1016/j.accpm.2025.101578,

PubMed Abstract | Crossref Full Text | Google Scholar

12. Wang, B, Tang, J, White, PF, Naruse, R, Sloninsky, A, Kariger, R, et al. Effect of the intensity of transcutaneous acupoint electrical stimulation on the postoperative analgesic requirement. Anesth Analg. (1997) 85:406–13. doi: 10.1213/00000539-199708000-00029,

PubMed Abstract | Crossref Full Text | Google Scholar

13. Wu, C, Deng, Z, Zhu, Y, Li, Y, Chen, Y, Wang, L, et al. Transcutaneous electrical acupoint stimulation accelerates gastrointestinal function recovery after abdominal surgery: a systemic review and meta-analysis of randomized controlled trials. Int J Surg. (2025) 111. doi: 10.1097/JS9.0000000000002946,

PubMed Abstract | Crossref Full Text | Google Scholar

14. Lu, Z, Wang, Q, Sun, X, Zhang, W, Min, S, Zhang, J, et al. Transcutaneous electrical acupoint stimulation before surgery reduces chronic pain after mastectomy: a randomized clinical trial. J Clin Anesth. (2021) 74:110453. doi: 10.1016/j.jclinane.2021.110453,

PubMed Abstract | Crossref Full Text | Google Scholar

15. Chen, J, Tu, Q, Miao, S, Zhou, Z, and Hu, S. Transcutaneous electrical acupoint stimulation for preventing postoperative nausea and vomiting after general anesthesia: a meta-analysis of randomized controlled trials. Int J Surg. (2020) 73:57–64. doi: 10.1016/j.ijsu.2019.10.036,

PubMed Abstract | Crossref Full Text | Google Scholar

16. Liu, Y, Fan, J, Zhang, X, Xu, W, Shi, Z, Cai, J, et al. Transcutaneous electrical acupoint stimulation reduces postoperative patients' length of stay and hospitalization costs: a systematic review and meta-analysis. Int J Surg. (2024) 110:5124–35. doi: 10.1097/JS9.0000000000001598,

PubMed Abstract | Crossref Full Text | Google Scholar

17. Gao, F, Zhang, Q, Li, Y, Tai, Y, Xin, X, Wang, X, et al. Transcutaneous electrical acupoint stimulation for prevention of postoperative delirium in geriatric patients with silent lacunar infarction: a preliminary study. Clin Interv Aging. (2018) 13:2127–34. doi: 10.2147/CIA.S183698,

PubMed Abstract | Crossref Full Text | Google Scholar

18. Ding, L, Ning, J, Guo, Y, Wang, Q, Kou, S, Ke, H, et al. The preventive effect of transcutaneous electrical Acupoint stimulation on postoperative delirium in elderly patients with time factors: a randomized trial. J Integ Complement Med. (2022) 28:689–96. doi: 10.1089/jicm.2021.0141,

PubMed Abstract | Crossref Full Text | Google Scholar

19. Zhang, L, Qiu, Q, and Zhou, L. The influence of transcutaneous electrical acupoint stimulation on fatigue and delirium in elderly patients with sleep disorders after lower extremity surgery. Guide Chin Med. (2025) 23:139–41.

Google Scholar

20. Ge, Y, Zheng, J, and Yu, Y. Effect of transcutaneous electrical acupoint stimulation on postoperative rehabilitation in elderly patients with kidney deficiency and blood stasis type undergoing hip replacement. Nurs Rehabil J. (2023) 22:50–52+55.

Google Scholar

21. Cao, L, Chen, Z, Yang, J, Ding, Z, and Meng, Z. Clinical study on preoperative transcutaneous electrical acupoint stimulation for postoperative delirium in elderly patients undergoing total hip replacement. Chin J Integ Med. (2022) 20:348–52.

Google Scholar

22. Wang, Q, Zhou, R, Ding, L, Ning, J, Kou, S, and Li, W. Effect of electroacupuncture and transcutaneous electrical acupoint stimulation on postoperative delirium in elderly patients. Chin J Surg Integ Trad West Med. (2022) 28:485–90.

Google Scholar

23. Zhang, Y, Gong, L, Zhang, Y, Dong, S, Shi, J, Li, X, et al. Effect of transcutaneous Acupoint electrical stimulation on urinary retention and urinary ATP in elderly patients after laparoscopic cholecystectomy: a prospective, randomized, controlled clinical trial. Clin Interv Aging. (2022) 17:1751–60. doi: 10.2147/CIA.S382912,

PubMed Abstract | Crossref Full Text | Google Scholar

24. Wei, L, Luo, W, Huang, J, Tai, S, Su, Y, Tang, Y, et al. The effect of transcutaneous electrical acupoint stimulation of Shenmen and Neiguan points on sleep quality and postoperative delirium in elderly patients undergoing hip replacement. Int J Anesth Resuscit. (2021) 42:1056–60.

Google Scholar

25. Yang, S, Zhong, B, and Zhong, W. Effect of transcutaneous electrical acupoint stimulation on postoperative delirium and its biomarkers in elderly patients with hip fracture. Mod Diagn Treat. (2023) 34:2272–4.

Google Scholar

26. Wu, H, Gao, H, Mi, Z, Lin, S, and Gao, J. Effect of transcutaneous electrical acupoint stimulation on postoperative delirium in frail elderly patients. Chin J Anesthesiol. (2021) 41:723–6.

Google Scholar

27. Chang, M, Long, Q, Lin, S, et al. Effect of transcutaneous electrical acupoint stimulation on postoperative fatigue and delirium in elderly patients with sleep disorder undergoing total hip arthroplasty. J Clin Anesthesiol. (2021) 37:1013–7.

Google Scholar

28. Shi, H, Li, W, Zhang, Y, and Wang, Y. Effect of transcutaneous electrical acupoint stimulation on sleep after spinal surgery in elderly. Orthop J China. (2022) 30:2045–9.

Google Scholar

29. Du, W, Zheng, J, Huang, M, and He, H. Effect of transcutaneous electrical acupoint stimulation on the incidence of postoperative delirium in elderly patients undergoing radical lung cancer surgery. J Anhui Med Coll. (2022) 21:30–31+34.

Google Scholar

30. Xu, X, Huang, X, Yu, Y, Wang, W, and Xia, P. Effects of percutaneous acupoint electrical stimulation assisted anesthesia on stress response and delirium after lumbar surgery in the elderly. Med Innov China. (2022) 19:53–7.

Google Scholar

31. Liu, W. Effects of transcutaneous acupoint electrical stimulation on postoperative delirium and early rehabilitation of elderly patients undergoing radical mastectomy. J Basic Clin Oncol. (2019) 32:400–4.

Google Scholar

32. Wen, M, and Liang, W. Effects of transcutaneous electric acupoint stimulation on postoperative stress response and delirium in elderly patients undergoing radical thyroidectomy. China Mod Doctor. (2025) 63:1–4.

Google Scholar

33. Yu, Y, Qian, X, Li, G, Tang, W, Li, C, and Liu, G. The effects of transcutaneous electrical acupoint stimulation on perioperative neurocognitive disorders and clinical outcomes in elderly patients undergoing open spinal surgery. J Wenzhou Med Univ. (2024) 54:1–6.

Google Scholar

34. Lu, F, Li, Y, Liu, T, et al. Effects of transcutaneous electrical acupoint stimulation on postoperative sleep quality in elderly patients undergoing proximal femoral bionic nail fixation surgery. J Clin Anesthesiol. (2025) 41:19–24.

Google Scholar

35. Wei, C, Hao, N, Liu, J, and Li, j. Observation on the effect of electrical stimulation at ghost points combined with an endotracheal general anesthesia on delirium in elderly patients after a total knee arthroplasty. Jilin J Chin Med. (2022) 42:362–5.

Google Scholar

36. Qian, J, He, M, Zhan, X, Ren, L, and Sun, Q. Transcutaneous electrical acupoint stimulation combined with an integrated perioperative nursing program prevents subsyndromal delirium in older patients after joint replacement. Geriatr Nurs (NY). (2023) 49:199–206. doi: 10.1016/j.gerinurse.2022.12.010,

PubMed Abstract | Crossref Full Text | Google Scholar

37. Li, Y, Ma, Y, Guo, W, Ge, W, Cheng, Y, Jin, C, et al. Effect of transcutaneous electrical acupoint stimulation on postoperative pain in pediatric orthopedic surgery with the enhanced recovery after surgery protocol: a prospective, randomized controlled trial. Anaesth Crit Care Pain Med. (2023) 42:101273. doi: 10.1016/j.accpm.2023.101273,

PubMed Abstract | Crossref Full Text | Google Scholar

38. Ma, JH, Liu, YF, Hong, H, Li, CJ, Cui, F, Mu, DL, et al. Effect of acute pain on the association between preoperative cognitive impairment and postoperative delirium: a secondary analysis of three trials. Br J Anaesth. (2023) 130:e272–80. doi: 10.1016/j.bja.2022.06.033,

PubMed Abstract | Crossref Full Text | Google Scholar

39. Vaurio, LE, Sands, LP, Wang, Y, Mullen, EA, and Leung, JM. Postoperative delirium: the importance of pain and pain management. Anesth Analg. (2006) 102:1267–73. doi: 10.1213/01.ane.0000199156.59226.af,

PubMed Abstract | Crossref Full Text | Google Scholar

40. Tan, Z, Dong, F, Wu, L, Xu, G, and Zhang, F. Transcutaneous electrical acupoint stimulation attenuated neuroinflammation and oxidative stress by activating SIRT1-induced signaling pathway in MCAO/R rat models. Exp Neurol. (2024) 373:114658. doi: 10.1016/j.expneurol.2023.114658

Crossref Full Text | Google Scholar

41. Chi, YL, Zhang, WL, Yang, F, Su, F, and Zhou, YK. Transcutaneous electrical Acupoint stimulation for improving postoperative recovery, reducing stress and inflammatory responses in elderly patient undergoing knee surgery. Am J Chin Med. (2019) 47:1445–58. doi: 10.1142/S0192415X19500745,

PubMed Abstract | Crossref Full Text | Google Scholar

42. Xiong, S, Wang, Q, Chen, Y, Du, H, and Zhao, Y. Leptin limits hepatic lipid accumulation and inflammation via vagal activation of the JAK2-STAT3/AMPK pathway. J Nutr Biochem. (2024) 134:109748. doi: 10.1016/j.jnutbio.2024.109748,

PubMed Abstract | Crossref Full Text | Google Scholar

43. Xue, H, Zhang, X, Chou, C, Jia, Y, Hao, C, and Duan, X. Advances in research on propofol-induced postoperative cognitive dysfunction via piezo channels. Front Mol Neurosci. (2025) 18:1668523. doi: 10.3389/fnmol.2025.1668523,

PubMed Abstract | Crossref Full Text | Google Scholar

44. Lu, Z, Huo, T, Deng, J, Guo, F, Liu, K, Liu, P, et al. Transcutaneous electrical acupoint stimulation induced sedative effects in healthy volunteers: a resting-state fMRI study. Front Hum Neurosci. (2022) 16:843186. doi: 10.3389/fnhum.2022.843186

Crossref Full Text | Google Scholar

Keywords: elderly, meta-analysis, perioperative, postoperative delirium, transcutaneous electrical acupoint stimulation

Citation: Chen Y-j, Shen Q-h, Yang Y, Shen R and Li H-f (2026) Transcutaneous electrical acupoint stimulation for preventing postoperative delirium in elderly patients: a systematic review and meta-analysis. Front. Med. 13:1717702. doi: 10.3389/fmed.2026.1717702

Received: 02 October 2025; Revised: 18 December 2025; Accepted: 02 January 2026;
Published: 15 January 2026.

Edited by:

Lei Zhao, Capital Medical University, China

Reviewed by:

Xuli Ren, Jilin University, China
Li-Xin An, Capital Medical University, China

Copyright © 2026 Chen, Shen, Yang, Shen and Li. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

*Correspondence: Hui-fang Li, bGlodWlmYW5nMjEzQDEyNi5jb20=

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