the effect of magnesium sulfate on post off-pump coronary artery bypass grafting bleeding

Abstract

Background: Magnesium level alteration may cause coagulation abnormality resulting in bleeding complication after off-pump coronary artery bypass grafting. In this study, we investigated the effect of magnesium on the postoperative coagulation profile and bleeding in OPCAB patients. Methods: In a double blind clinical trial, six hundred patients were randomly allocated to two groups: group A (n = 150) and group B (n = 450). Group A received 50 mg/kg of magnesium sulfate (MS) in 100 ml 0.9% NaCl solution over 20 min before the anesthesia induction. Group B or control group received only 100 ml 0.9% NaCl solution at the same time points. OPCAB was performed with standard technique and device. Blood samples were collected 30 min before and 6 h after the surgery to analyze hemoglobin and blood coagulation tests. Postoperative exploration for bleeding, blood transfusion, and volume of transfusion was recorded. The two groups compared with t-test and χ2 tests and p-valve <0.05 were considered as significant. Results: However, postoperative hemoglobin was statistically lower in group A compared with group B, but platelet, PT, and aPTT tests were not statistically different between two groups. The serum MS level, exploration for bleeding, volume of packed cell transfusion, and volume of postoperative bleeding were statistically different between group A vs group B. Conclusion: Preoperative MS use may be associated with the postoperative platelet dysfunction and increased tendency to bleeding. This is an important risk factor for postoperative bleeding in the OPCAB in absence of CPB use.