Transcutaneous Electrical Acupoint Stimulation Combined with General Anesthesia in Minimally Invasive Surgery for Lung Cancer: A Randomized, Patient- and Assessor-Blinded, Sham-Controlled Trial

Background: We aimed to clarify (1) the analgesic efficacy of transcutaneous electrical acupoint stimulation (TEAS) combined with general anesthesia during minimally invasive lung cancer surgery and (2) exploratory neural network correlates of acupuncture–drug combined anesthesia. Methods: Eligible patients receiving general anesthesia for minimally invasive lung cancer surgery were randomly allocated to perioperative TEAS or sham-TEAS in this randomized, patient- and assessor-blinded, sham-controlled trial. Postoperative patient-controlled intravenous analgesia (PCIA) was administered. Outcome measures included postoperative visual analog scale (VAS) pain scores, sufentanil consumption via PCIA, and total/effective PCIA pump presses. Perioperative electroencephalography (EEG) was acquired using a 22-lead recorder, and brainwave power spectra were analyzed using Fourier transform. Repeated-measures analysis of variance (RM-ANOVA) was applied to serial postoperative VAS scores at 6, 24 and 48 h. Independent-samples t-tests compared cumulative sufentanil consumption at 6, 24 and 48 h postoperatively. Post hoc simple-effect comparisons were performed as exploratory analyses without multiplicity adjustment. The EEG sub-study was exploratory; false-discovery-rate (FDR) correction was used to control multiple comparisons across electrodes and frequency bands. Results: In total, 109 patients were randomized. A significant group-by-time interaction was detected for postoperative VAS scores (F(1.599,171.124) = 68.287, p < 0.001). Simple-effect analyses revealed lower VAS scores in the TEAS group at postoperative 6 h (mean difference −1.900, 95%CI −2.181 to −1.619, p < 0.001) and 24 h (mean difference −1.391, 95%CI −1.645 to −1.138, p < 0.001), with no between-group difference at 48 h (mean difference −0.066, 95%CI −0.320 to 0.187, p = 0.605). The TEAS group also exhibited reduced PCIA sufentanil consumption at 6, 24 and 48 h postoperatively, alongside fewer total and effective PCIA pump presses. After FDR correction, exploratory EEG analysis identified potential dipole-related power differences in the prefrontal, occipital, parietal (postcentral gyrus), temporal and diencephalic regions, predominantly within beta-band oscillations (14–35 Hz). Conclusions: These exploratory findings suggest that TEAS combined with general anesthesia may reduce postoperative pain and analgesic requirement. This potential benefit may arise from TEAS-mediated modulation of pain-related neural networks; however, the observed intraoperative EEG oscillatory differences are exploratory neurophysiological correlates and do not confirm causal mechanisms.