GPT and infection: Chronic opioid therapy in the previous 3 months before surgery, conversion to open surgical technique, BMI > 30 kg/m2or < 18 kg/m2, postoperative recovery in intensive care unit, chronic therapy with antidepressants, known diagnosis of epilepsy or therapy with antiepileptic drugs, bilirubin level > 3.0 mg/dL, aspartate aminotransferase and/or alanine aminotransferase > 250 IU, creatinine level >1.4 mg/dL, pregnancy or lactation, known allergy to any drug used in the study, local infection at the block site, and drug or alcohol addiction.