Effect of endovenous lidocaine on analgesia and serum cytokines: double-blinded and randomized trial

Abstract

Study objective: This trial aimed to compare postoperative analgesia, opioid consumption, duration of ileus and hospital stay, and cytokine levels in patients undergoing laparoscopic cholecystectomies who received intravenous lidocaine in comparison with a control group.

Design: Prospective, longitudinal, double-blind, and randomized study.

Setting: Operating room and postoperative recovery area.

Patients: Forty-four American Society of Anesthesiologists I and II patients older than 17 years, undergoing laparoscopic cholecystectomy, under general anesthesia.

Interventions: The first group received intravenous lidocaine during the procedure until 1 hour postoperatively, whereas the second group received saline. Both groups received dipyrone and morphine patient-controlled analgesia.

Measurements: Pain was assessed by Visual Numeric Scale at rest and when coughing at different times after the end of the surgery. Blood samples were taken at the end of procedure and 24 hours later. The total morphine patient-controlled analgesia demand, the time for the first flatus, and the length of hospital stay were also recorded.

Main results: Groups were similar in relation to sex (P= .2), age (P= .5), weight (P= .08), and length of surgery (P= .6). No differences were observed regarding the intensity of postoperative pain between the groups, either at rest (P= .76) or when coughing (P= .31), in morphine consumption (P= .9), and in the duration of ileus (P= .5) or length of hospital stay (P= .9). The inflammatory markers interleukin (IL)-1 (P= .02), IL-6 (P< .01), interferon-γ (P< .01), and tumor necrosis factor α (P< .01) showed significant reduction in the lidocaine group against the placebo group, except IL-10 (P= .01), that, because of its anti-inflammatory effects, increased its concentration.

Conclusions: Intravenous lidocaine was not able to reduce postoperative pain, opioid consumption, and duration of ileus or length of hospital stay. However, its anti-inflammatory effect was noticeable.

Keywords: Analgesia; Cytokines; Lidocaine; Postoperative pain.