Continuous infusion of intraoperative dexmedetomidine improves chronic pain after thoracotomy via the Toll-like receptor 4/nuclear factor kappa B signaling pathway

Objectives: To explore the role of continuous infusion of intraoperative dexmedetomidine in chronic pain after thoracotomy via the Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-kappa B) signaling pathway. Methods: Seventy-five patients undergoing thoracotomy were randomized into the control group (CG, n=37) and the observation group (OG, n=38). After induction of anesthesia for 30 min and until the end of surgery, the OG was infused with 0.4 mu g/(kgh) dexmedetomidine, and the CG was infused with the same amount of normal saline. Results: After operation, the OG had lower mean arterial pressure, heart rate, visual analogue scale (VAS) scores, incidence of chronic pain and neuropathic pain, TLR4 and NF-kappa B expressions, and tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) levels as well as epinephrine and norepinephrine levels than the CG (P < 0.05). The number of times the patient pressed the button for pain medication and the dose administered in the OG were less than those in the CG (P < 0.05). Conclusion: Continuous infusion of intraoperative dexmedetomidine can maintain perioperative hemodynamic stability in patients undergoing thoracotomy and reduce the stress response, postoperative pain, consumption of analgesic drugs, and the incidence of post-chronic and neuropathic pain, which is closely related to the reduction of inflammation via the TLR4/NF-kappa B signaling pathway.