Transcutaneous auricular vagus nerve stimulation improves postoperative recovery quality in patients undergoing thyroid surgery by inhibiting the inflammatory response: a randomized controlled trial.

OBJECTIVE

This randomized controlled trial evaluated whether perioperative transcutaneous auricular vagus nerve stimulation (taVNS) improves recovery quality after thyroid surgery and explored a mediating role of the inflammatory response.

METHODS

A total of 120 patients undergoing thyroid surgery were randomly allocated to active taVNS (cavum conchae) or sham stimulation (earlobe). The primary outcome was the Quality of Recovery-40 (QoR-40) score at 24 h; secondary outcomes included pain scores, postoperative nausea and vomiting (PONV), hospital stay, and interleukin-6 (IL-6)/tumor necrosis factor-α (TNF-α) levels. Linear mixed models with false-discovery-rate correction were used.

RESULTS

The taVNS group showed a higher adjusted QoR-40 score (β=7.41, P=0.0068), lower pain scores, reduced PONV incidence, and shorter hospital stay (all P<0.05). IL-6 and TNF-α mediated 27.7% and 26.1% of the recovery benefit, respectively (both P<0.001). Preoperative QoR-40 score independently predicted taVNS response (OR=0.30, P=0.008). No serious adverse events occurred.

CONCLUSION

Perioperative taVNS safely improves postoperative recovery, partly through inhibiting IL-6/TNF-α, with consistent benefits across patient subgroups. Preoperative QoR-40 may help identify optimal candidates, aligning with enhanced recovery after surgery (ERAS) principles.