Effect of Intravenous Lidocaine on BIS-guided Propofol Requirements During General Anesthesia

Estimation of the Effect of Intravenous Lidocaine on BIS-guided Propofol Requirements During General Anesthesia

The purpose of this randomized clinical trial is to evaluate the interaction of lidocaine infusion initiated and maintained during surgery, on propofol requirements during general anesthesia.

Use of intravenous lidocaine as a coadjuvant agent during general anesthesia has increased. Lidocaine infusion during and after abdominal surgery decreases postoperative pain and reduces ileus duration, reducing patient´s hospital stay and opioid consumption. Intravenous lidocaine´s effect on other intravenous anesthetics is unclear, and there are no present studies evaluating its interaction on hypnotic anesthetic requirements when using a BIS (Bispectral Index) monitor to maintain an adequate depth of anesthesia. We therefore decided to conduct a randomized controlled trial to evaluate the interaction of systemic lidocaine infusion, initiated and maintained during surgery, on propofol requirements and anesthetic depth as measured by BIS.

Inclusion Criteria:

• ASA I-II patients,
• Between 20 and 65 years of age
• Programed for elective laparoscopic cholecystectomy
• Eligible for total intravenous anesthesia with propofol

Exclusion Criteria:

• Unwillingness to participate in the study
• Adverse reactions to the drugs used in the study
• Use of medications that interfere in local anesthetic metabolism
• History of liver disease, kidney failure, hypoalbuminemia, hypocalcemia or hypophosphatemia
• History of drug or alcohol abuse
• Chronic use of benzodiazepines