Effect of lidocaine infusion compared to dexmedetomidine infusion on proinflammatory cytokines and stress response in pelvi-abdominal cancer a randomized clinical trial

Background & Objectives: Stress response to extensive surgeries in cancer patients results in an imbalance between the pro-inflammatory and anti-inflammatory cytokines, besides activating an inflammatory cascade. We investigated the comparative effects of intravenous infusion of dexmedetomidine and lidocaine on proinflammatory cytokines and the stress reaction. Methodology: A prospective randomized double blind trial was performed in National Cancer Institute. 54 patients scheduled for pelvi-abdominal cancer surgery under general anesthesia were randomly allocated to three equal groups. Lidocaine group: patients received 1.5 mg/kg loading dose of lidocaine followed by 1.5 mg/kg/h infusion; Dexmedetomidine group: received a loading dose of dexmedetomidine 1 mu g/kg followed by infusion of 0.5 mu g/kg/h; or Saline group: received 50 ml of normal saline followed by infusion at a rate of 10 ml/h till the end of the surgery. The primary outcome was a postoperative target level of IL-6 after 24 h. Results: Immediate and 24 h postoperative IL-6 and TNF alpha were significantly lower in both dexmedetomidine and lidocaine groups compared to the control group (P < 0.001). Dexmedetomidine group had a significantly lower IL-6 and TNF alpha levels compared to lidocaine group at immediate postoperative and 24 h postoperative period (P < 0.001). Dexmedetomidine and lidocaine groups had a significantly lower lactate and insulin levels compared to the control group immediately postoperatively as well as 24 h postoperatively (P < 0.001). The dexmedetomidine group had a significantly lower lactate levels compared to the lidocaine group immediately postoperatively only. The lidocaine group had lower insulin level than the control group regarding immediate postoperative period only. Conclusion: Intraoperative infusion of dexmedetomidine or lidocaine, both attenuate the postoperative levels of proinflammatory cytokines and stress response in patients undergoing pelvi-abdominal cancer surgeries.