Comparison Study of Transversus Abdominal Plane, Paravertebral and Epidural Blocks in Laparoscopic Colectomy

Inclusion Criteria * Male or female, ≥ 18 years of age * Patients scheduled to undergo laparoscopic colectomy without stoma under general anesthesia * American Society of Anesthesiology (ASA) Physical Class 1-3. Exclusion Criteria: * Open colectomy * Perineal resection * Stoma formation * Patients with a contraindication to TEA or regional anesthesia. * Pregnancy, nursing, or planning to become pregnant during the study or within one month. * Long-acting opioid medication within 3 days. * Any opioid medication within 24 hours. * Body weight less than 50 kilograms (\~110 pounds) * Uncontrolled anxiety, schizophrenia, or other psychiatric disorder * Current or historical evidence of any clinically significant disease or condition that, in the opinion of the Investigator, may increase the risk of surgery or complicate the subject's postoperative course. * Administration of an investigational drug within 30 days or 5 elimination half-lives of such investigational drug, whichever is longer, prior to study drug administration, or planned administration of another investigational product or procedure during the subject's participation in this study. * Suspected, or known addiction to or abuse of illicit drug(s), prescription medicine(s), or alcohol within the past 2 years. * Significant medical conditions or laboratory results that, in the opinion of the Investigator, indicate an increased vulnerability to study drugs and procedures, and expose the subject to an unreasonable risk as a result of participating in this clinical trial, such as: debilitating diseases, acute illnesses, hypotension, partial or complete conduction block, impaired cardiac function, untreated hypertension, advanced arteriosclerotic heart disease, cerebral vascular insufficiency, pre-existing abnormal neurological or neuromuscular disease (e.g., epilepsy, myasthenia gravis), advanced liver disease, severe renal impairment, advanced diabetes, comorbid conditions associated with an immunocompromised status, such as blood dyscrasias, HIV/AIDS, or recent chemotherapy.