Effect of Transcranial Alternating Current Stimulation on Prevention of Postoperative Pain After Video-Assisted Thoracic Surgery: A Randomized Controlled Trial.

INTRODUCTION

Transcranial alternating current stimulation (tACS), which can noninvasively entrain oscillatory brain activity, has attracted scientific attention as a possible technique to control pain. However, there is a scarcity of studies investigating the preventive effect of tACS on postoperative pain.

METHODS

This double-blind, randomized, sham-controlled trial enrolled 72 patients undergoing elective video-assisted thoracoscopic surgery (VATS). Patients were randomly allocated (1:1) to receive a single 20-min session of α-tACS on the primary somatosensory cortex (S1) or sham stimulation postoperatively. The primary outcomes were postoperative numerical rating scale pain scores and opioid consumption at 24 h postoperatively. Secondary outcomes included cumulative opioid consumption within 48 h and Quality of Recovery-15 (QoR-15) score. Adverse events were also assessed.

RESULTS

The tACS group exhibited significantly lower resting pain scores versus the sham group (β = -0.49, 95% confidence interval [CI], -0.78 to -0.20, p = 0.001) and lower movement pain scores versus the sham group (β = -0.45, 95% CI, -0.84 to -0.06, p = 0.025), though cumulative opioid consumption showed no difference at 24 h (median difference [MD] = 1.0 mg; 95% CI, -2.3 to 2.5; p = 0.76) and 48 h (MD = 3.3 mg; 95% CI, -0.6 to 9.1; p = 0.10) postoperatively. Additionally, the area under the curve for resting pain over 2-24 h (AUC2-24 h) and 2-48 h (AUC2-48 h), as well as the AUC2-48 h of movement pain scores, were significantly lower in the tACS group. Moreover, QoR-15 scores and adverse events were also comparable.

CONCLUSION

For patients undergoing VATS, a single α-tACS treatment targeting the bilateral S1 regions yielded a statistically significant yet modest reduction in postoperative pain. However, no significant decrease in postoperative opioid consumption was observed, and further research is warranted.

TRIAL REGISTRATION: Chinese Registry of Clinical Trials: ChiCTR2300078723.