Synergistic effect of the association between lidocaine and magnesium sulfate on peri-operative pain

Synergistic effect of the association between lidocaine and magnesium sulfate on peri-operative pain after mastectomy: A randomised, double-blind trial: BACKGROUND

Recently, the use of venous adjuvants, such as lidocaine and magnesium sulfate, has been gaining ground in multimodal analgesia. However, no study has evaluated the impact a combination of the two drugs.

OBJECTIVES

To evaluate the efficacy of venous adjuvants in reducing opioid consumption and pain scores after mastectomy.

DESIGN

Randomised, double-blind, parallel-group, noninferiority clinical trial with a 1 : 1 : 1 : 1 allocation ratio.

SETTING

Hospital de Base do Distrito Federal, Brasilia, Federal District, Brazil from November 2014 to December 2017.

PATIENTS

One-hundred and ninety-eight patients were electively scheduled for mastectomy. Seventy-eight were excluded.

INTERVENTIONS

Intra-operative infusions of remifentanil (0.1 μg kg−1 min−1), lidocaine (3 mg kg−1 h−1), magnesium sulfate (50 mg kg−1 + 15 mg kg−1 h−1) or lidocaine with magnesium sulfate were used. All patients received standard general anaesthesia.

MAIN OUTCOME MEASURES

Peri-operative opioid consumption and pain scores.

RESULTS

The patients who received both lidocaine and magnesium sulfate group (n=30) consumed less alfentanil during surgery (P