NCT07073846

Effect of Lidocaine-Dexmedetomidine on Pain, Inflammation, and Oxidative Stress After Bariatric Surgery.

Efficacy of Lidocaine-Dexmedetomidine Combination Therapy in Reducing Post-Operative Pain, Inflammatory Response, and Oxidative Stress in Patients Undergoing Bariatric Surgery

• Status: Recruiting
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 104 (estimated)
• Sponsor: Instituto Mexicano del Seguro Social · Other Government
• Sex: All
• Age: 18 Years – 60 Years
• Healthy volunteers: Not accepted

Summary

The goal of this randomized clinical trial is to find out whether giving an intravenous lidocaine + dexmedetomidine combination (LIDEX) during laparoscopic bariatric surgery can lower post-operative pain, inflammation, and oxidative stress in adults with obesity. The main questions it aims to answer are: * Pain control: Does LIDEX reduce pain 24 hours after surgery, as measured with the International Pain Outcomes Questionnaire (IPOQ)? * Biomarkers: Does LIDEX lower blood levels of key inflammatory cytokines-interleukin-1 beta (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and interleukin-10 (IL-10)-and oxidative-stress markers-malondialdehyde (MDA), the reduced/oxidized glutathione ratio (GSH/GSSG), superoxide dismutase (SOD), and catalase-compared with the individual drugs or saline placebo? Researchers will compare four groups: lidocaine alone, dexmedetomidine alone, LIDEX, and placebo (saline solution, a look-alike substance that contains no drug) to learn which approach works best. Participants will: * Receive an intravenous infusion of their assigned study drug(s) during surgery. * Provide three small blood samples (before surgery, immediately after, and three hours after). * Complete a short pain questionnaire (IPOQ) 24 hours after surgery.

Detailed description

Obesity is associated with chronic low-grade inflammation and persistent oxidative stress. Laparoscopic bariatric surgery-although highly effective for weight reduction-triggers an acute inflammatory cascade and a burst of reactive oxygen species that can amplify post-operative pain and delay functional recovery. Intravenous lidocaine stabilises voltage-gated Na+ channels, limits ectopic neuronal firing and inhibits neutrophil priming; it also down-regulates the release of pro-inflammatory cytokines in abdominal procedures. Dexmedetomidine, a highly selective α2-adrenergic agonist, produces sedation and analgesia while attenuating sympathetic outflow, thereby reducing surgical catecholamine surges and cytokine release. Pre-clinical and clinical synergy studies indicate that combining these two agents (LIDEX) can provide additive anti-hyperalgesic, anti-inflammatory and antioxidant effects without increasing cardiovascular risk when each is dosed within its established therapeutic window. In this protocol, a weight-adjusted intra-operative infusion of lidocaine plus dexmedetomidine is administered during bariatric surgery and compared with each single agent and saline. Peri-operative venous samples are collected for mechanistic profiling of systemic inflammatory and redox responses, and patient-reported pain is captured after surgery using a validated instrument. Haemodynamic parameters are continuously monitored to detect potential lidocaine toxicity or dexmedetomidine-related bradycardia and hypotension; predefined rescue algorithms are applied if thresholds are exceeded. The study is designed to clarify whether the LIDEX combination can blunt the acute inflammatory-oxidative surge thought to drive sustained pain and metabolic stress after bariatric surgery, thereby informing future enhanced-recovery protocols that integrate multimodal analgesia with metabolic optimisation strategies.

Conditions

• Morbid Obesity Requiring Bariatric Surgery
• Postoperative Pain
• Postoperative Pain Management
• Postoperative Analgesia
• Postoperative Adjuvant Treatment
• Postoperative Inflammatory Markers
• Postoperative Inflammatory Response

Interventions

Type	Name	Description
DRUG	Intravenous Lidocaine infusion + Standard Anesthesia	Continuous IV infusion of lidocaine 1 % (10 mg mL-¹) at 0.3 mL kg-¹ h-¹ (≈ 1.5 mg kg-¹ h-¹) from induction of anaesthesia to skin closure. No loading bolus, no post-operative infusion.
DRUG	Intravenous Dexmedetomidine infusion + Standard Anesthesia	Continuous IV infusion of dexmedetomidine 1 µg mL-¹ at 0.3 mL kg-¹ h-¹ (≈ 0.3 µg kg-¹ h-¹) without loading dose, started after induction and stopped at skin closure. No post-operative infusion.
DRUG	Lidocaine + Dexmedetomidine Combination (LIDEX) + Standard Anesthesia	Single syringe containing lidocaine 1 % (10 mg mL-¹) + dexmedetomidine 1 µg mL-¹, infused IV at 0.3 mL kg-¹ h-¹ (delivering ≈ 1.5 mg kg-¹ h-¹ lidocaine + 0.3 µg kg-¹ h-¹ dexmedetomidine) from induction to skin closure.
DRUG	0.9 % Saline Placebo + Standard Anesthesia	Volume-matched IV infusion of 0.9 % normal saline at 0.3 mL kg-¹ h-¹ for the same duration and through the same delivery line as active arms; identical syringe appearance.

Timeline

• Start date: 2025-10-06
• Primary completion: 2027-05-01
• Completion: 2027-07-01
• First posted: 2025-07-18
• Last updated: 2025-11-28

Locations

2 sites across 1 country: Mexico