To the Editor,
We read with great interest the network meta-analysis by Zhou et al[1] comparing acupoint stimulation techniques for preventing postoperative nausea and vomiting (PONV). This comprehensive study provides robust evidence supporting transcutaneous electrical acupoint stimulation (TEAS) and electroacupuncture as effective non-pharmacological strategies. This correspondence complies with the TITAN Guidelines 2025 for AI ethics in academic writing[2].While we commend the authors’ work, we wish to highlight three underexplored dimensions that could strengthen clinical translation:
1. Neurobiological Mechanisms Underlying Electrical Stimulation Efficacy
The superior efficacy of electrical stimulation (TEAS/electroacupuncture) over manual methods (acupressure) warrants deeper mechanistic contextualization. Low-frequency TEAS (2 Hz) promotes endogenous opioid release—specifically endorphins and enkephalins—which inhibit the chemoreceptor trigger zone and vomiting center[3]. Conversely, high-frequency stimulation (100 Hz) enhances dynorphin release, mediated by κ-opioid receptors[4]. These frequency-dependent neurochemical responses mirror clinical observations; for instance, TEAS applied at PC6 has been shown to reduce PONV incidence by nearly 50% within the first 24 hours postoperatively[5]. Future studies correlating biomarker dynamics (e.g., β-endorphins, serotonin) with PONV outcomes would bridge efficacy and mechanism.
2. Personalized Application for High-Risk Cohorts
While Zhou et al. identify abdominal/gynecological surgery and female sex as risk factors, efficacy stratification by Apfel score or pharmacogenomic profiles remains unexplored. TEAS reduces PONV incidence by 33.4 percentage points (from 56.7% to 23.3%) in gynecological laparoscopy patients[6], but its benefit in opioid-dependent or genetically susceptible subgroups is unclear. Genetic polymorphisms (e.g., HTR3B rs1176744) significantly influence antiemetic response in women with nausea and vomiting of pregnancy[7], suggesting combined TEAS and pharmacogenomic strategies may optimize outcomes. Risk stratification using validated tools (e.g., Apfel score ≥3) could guide tailored interventions.
3. Standardization of Stimulation Parameters
Substantial heterogeneity exists in TEAS protocols across trials. For instance, frequency specificity critically influences neurochemical responses: 2 Hz stimulation preferentially releases endorphins and enkephalins, whereas 100 Hz selectively activates dynorphin pathways[4]. Consequently, establishing consensus on optimal parameters—such as prioritizing 100 Hz for intraoperative prophylaxis versus 2 Hz for postoperative maintenance—is imperative to ensure methodological reproducibility and clinical translation.
Conclusion
Zhou et al.’s work establishes a foundation for non-pharmacological PONV management. Future efforts should: (i) validate mechanisms via biomarker studies, (ii) develop risk-stratified protocols, and (iii) standardize frequency and duration parameters. These steps could facilitate the integration of non-pharmacological interventions into perioperative guidelines.
Acknowledgements
We are particularly grateful to Mingxiang Zheng for her invaluable guidance and insightful suggestions throughout this study.
Footnotes
Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article.
Contributor Information
Xiangjiang Tang, Email: 515368644@qq.com.
Yang Yang, Email: 963486993@qq.com.
Ethical approval
Ethical approval is not applicable for this correspondence article.
Consent
Informed consent is not applicable for this correspondence article.
Funding
None.
Author contributions
X.T., Y.L., and Y.Y. were responsible for the conceptualization of the study. The original draft of the manuscript was written by X.T., Y.L. All authors participated in the review and editing process, ensuring the accuracy and integrity of the work presented.
Conflicts of interest disclosure
The authors affirm that there are no competing interests.
Guarantor
Yilin Li.
Research registration unique identifying number (UIN)
None.
Provenance and peer review
None.
Data availability statement
Data sharing is not applicable to this article as no new data were created or analyzed in this study.
References
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Associated Data
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Data Availability Statement
Data sharing is not applicable to this article as no new data were created or analyzed in this study.