External Oblique Intercostal Block With or Without Intravenous Lidocaine Infusion for Analgesia in Patients Undergoing Gastric Bypass Surgery

External Oblique Intercostal Block With or Without Intravenous Lidocaine Infusion for Analgesia in Patients Undergoing Gastric Bypass Surgery: a Randomized Controlled Trial

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.

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.