Intraoperative Magnesium Sulfate can Reduce Narcotic Requirement after Coronary Bypass Surgery

Background: Narcotics are the most common drugs that have been used after cardiac surgery. Everyone knows that their side effects including respiratory depression, he- modynamic instability, and nausea, vomiting and itching are dose dependent. Magne- sium is both N Methyl D Aspartate (NMDA) – receptor and calcium receptor antago- nist and can modify important mechanisms of nociception. The purpose of this study was to investigate the effect of magnesium sulfate on pain score and reducing narcotic requirement in coronary artery bypass surgery patients. Methods: In a randomized, double blinded, placebo-controlled trial One hundred and eighty five patients (105 male and 80 female) undergoing elective coronary artery bypass graft surgery were studied. Mean age were 58+_11 (from 24 to79 years).We enrolled them in two groups randomly. Group1 received magnesium sulfate as an IV infusion 80 mg/kg during one hour after induction and the second group received the same volume of normal saline as placebo. During the postoperative period, Morphine requirement and pain score (visual analogue scale: scaled as 0 to 10, 0=no pain and 10= worst possible pain) in 6, 12, 18, and 24 hours were recorded and documented. Results: There were no significant differences between two groups with respect to baseline data. In MG group, only 30 patients (32%) needed to receive Morphine Sul- fate , but in placebo group, 75 patients (83%) needs some doses of Morphine Sulfate (p value 0.001); The odds ratio showed that MG could strongly prevent the needs for receiving opioid analgesics for controlling of the pain. Conclusion: Intra operative use of magnesium sulfate can reduce receiving opioids after (CABG) operations.