Lidocaine and the inhibition of postoperative pain in coronary artery bypass patients

Abstract

Objective: This study was designed to evaluate whether a continuous low-dose lidocaine infusion reduces postoperative pain and anxiety in patients undergoing coronary artery bypass grafting (CABG) and to retrospectively examine time to extubation, intensive care unit stay (ICU), and hospital length of stay.

Design: A double-blinded, randomized, and prospective approach.

Setting: Hospital patients undergoing first-time CABG.

Participants: After informed consent, 100 patients were enrolled in this study.

Interventions: Lidocaine infusion or placebo substitute was begun after induction of anesthesia. The fentanyl/midazolam infusion was discontinued on ICU admission; lidocaine or placebo continued until ICU discharge. Supplemental fentanyl, midazolam, or propranolol was administered for pain, anxiety, or hemodynamic stress.

Measurements and main results: Drug dosages were compared between groups. Postoperative assessment included visual analog pain score, hemodynamics, sedation score, and nursing assessment. Mean total dosages of fentanyl, midazolam, and propranolol between the lidocaine and placebo groups were 620.40 +/- 815.74 microgram versus 689.16 +/- 692.99 microgram, p = 0.244; 0.54 +/- 1.13 mg versus 1.20 +/- 2.44 mg p = 0.465; 0.11 +/- 0.75 mg versus 3.56 +/- 17.2 mg, p = 0.564, respectively. Times to extubation, ICU length of stay, and hospital stay did not achieve statistical significance.

Conclusions: Continuous infusion of low-dose lidocaine did not significantly decrease supplemental fentanyl, midazolam, or propranolol requirement postoperatively. Similarly, a lidocaine infusion does not result in reduced time to extubation. ICU stay, or hospital length of stay.