The effect of tDCS on postoperative opioid consumption and pain after general anesthesia: a systematic review and meta-analysis of randomized controlled trials

Complement Ther Med. 2025 Oct 31:103303. doi: 10.1016/j.ctim.2025.103303. Online ahead of print.

ABSTRACT

BACKGROUND: Transcranial direct current stimulation (tDCS), as a supplementary plan during the perioperative period, is currently a novel exploration of using neuromodulation techniques to improve postoperative symptoms.

METHODS: We searched Embase, PubMed, EBSCO, Web of Science, Scopus, and Cochrane Library databases on February 17, 2025. The primary outcomes included postoperative opioid drug consumption and pain score. The secondary outcomes included fatigue, anxiety, depression, quality of recovery, sleep quality, and adverse events. The study was conducted using Review Manager 5.4 software.

RESULTS: We ultimately included 13 trials, including 827 participants (442 in the real tDCS group and 385 in the sham group). Within these trials, two had some concerns, and eleven were low-risk. In terms of primary outcomes, tDCS could significantly reduce postoperative opioid consumption (SMD = -0.52, 95%CI = [-0.77, -0.27]; P ＜ 0.001), pain score (SMD = -0.48, 95%CI = [-0.66, -0.29], P < 0.001). For secondary outcome, tDCS led to a significant decrease in the fatigue score (SMD = -4.35, 95%CI = [-4.73, -3.98], P ＜ 0.001). However, there were no statistically differences in anxiety (SMD = -0.98, 95% CI = [-2.16, 0.21], P = 0.110). tDCS could increase adverse event (RR = 3.88, 95% CI = [1.64, 9.19], P = 0.002), but these events were mild and temporary. Due to the limited number of trials on postoperative recovery quality, depression, and sleep quality, we conducted only a review and did not include these outcomes in the meta-analysis.

CONCLUSIONS: tDCS can reduce postoperative opioid consumption and effectively alleviate postoperative pain. Regarding secondary outcomes, although the results suggest it may reduce postoperative fatigue, this conclusion requires further validation due to the limited number of studies included.More studies are needed in the future to provide evidence on the effects of tDCS on fatigue, anxiety, depression, quality of recovery and sleep quality.

PMID:41177366 | DOI:10.1016/j.ctim.2025.103303