The effect of intravenous magnesium sulfate on serum levels of N-terminal pro-brain natriuretic peptide (NT pro-BNP) in elective CABG with cardiopulmonary bypass

Abstract

Nowadays, many patients undergo coronary artery bypass grafting (CABG) with a cardiopulmonary bypass (CPB); while a number of therapeutic agents have been used to suppress its related inflammatory process. Magnesium sulfate (MgSO4) solution has been used as an anti-inflammatory agent. Among the cardiac biomarkers, N-terminal pro brain natriuretic peptide (NT Pro-BNP) is one of the most widely recognized. We performed this study to assess the effect of MgSO4 solution on NT Pro-BNP levels in patients undergoing CABG with CPB. In a double-blind clinical trial, after IRB approval for ethical considerations, during a 12-month period, 88 adult patients aged 40-70 years qualified for the study after inclusion and exclusion criteria were considered. After random allocation of the patients between the two groups, anesthesia, surgical procedure, cardiopulmonary bypass (CPB) methods, and postoperative care were made as similar as possible; however, one group received a MgSO4 infusion (15 mg/kg/h) and the other group saline (placebo). Pre- and post-operative levels of NT Pro-BNP were assessed using an electrochemical luminescence immunoassay in an Elecsys 2010 (Roche, Indianapolis, IN, USA). The results were compared using a Student's t-test. A P value less than 5% was considered significant. The MgSO4 group had shorter postoperative mechanical ventilation, lower postoperative morphine requirements and lower postoperative pain scores. Also, 24 h postoperative NT Pro-BNP levels were significantly lower in the MgSO4 group. Administration of MgSO4 in elective CABG with CPB can decrease the postoperative NT Pro-BNP levels; also, it decreases their time of postoperative mechanical ventilation.