Overview
Adding a perioperative lidocaine infusion (1.5 mg/kg loading + 1.5 mg/kg/h) to bilateral EOIB and low dose fentanyl loading reduces intraoperative fentanyl consumption (ANI guided rescue) compared to placebo, without increasing adverse events.
Eligibility
Inclusion Criteria:
- Age 18-60 years.
- BMI ≥ 35 kg/m².
- ASA physical status II or III.
- Scheduled for elective laparoscopic Roux en Y gastric bypass.
- Ability to provide written informed consent.
Exclusion Criteria:
- Refusal.
- Allergy or contraindication to lidocaine, fentanyl, ropivacaine, or any study medication.
- Chronic opioid use or dependence.
- Significant hepatic (AST/ALT\> 3× normal, cirrhosis) or renal impairment (CrCl\< 30 mL/min).
- Second or third degree AV block or significant bradyarrhythmia without pacemaker.
- Coagulopathy, anticoagulation incompatible with regional anesthesia, or infection at block site.
- Pregnancy or lactation.
- Severe psychiatric or cognitive disorder.
- Failed bilateral EOIB (absence of sensory loss in T6-T10 after 30 min) - excluded from analysis.
