Dingchao He1, Nimisha Aggarwal2, David Zurakowski3, Richard A Jonas1, Charles I Berul2, Sridhar Hanumanthaiah2, Jeffrey P Moak4. 1. Division of Cardiovascular Surgery, Children's National Health System, Washington, DC. 2. Division of Cardiology, Children's National Health System, Washington, DC. 3. Departments of Anesthesiology and Surgery, Boston Children's Hospital, Harvard Medical School, Boston, Mass. 4. Division of Cardiology, Children's National Health System, Washington, DC. Electronic address: jmoak@childrensnational.org.
Abstract
OBJECTIVES: Postoperative arrhythmias are common in children undergoing congenital heart surgery. We evaluated whether intraoperative administration of magnesium was associated with a reduced occurrence of specific postoperative arrhythmias, as has been described previously, or had a broader effect on multiple arrhythmia types, and whether there existed a dose-effect of intraoperative magnesium. METHODS: We used a historical prospective observational cohort study. Propensity score matching using logistic regression was applied to establish similar populations of treatment groups balanced on 5 important covariates. RESULTS: Based on propensity score-matched groups, magnesium 50 mg/kg administration was associated with a reduced odds of occurrence of postoperative arrhythmias: any arrhythmia (odds ratio [OR] = 0.50, P < .001), junctional ectopic tachycardia (OR = 0.56, P = .004), accelerated junctional rhythm (OR = 0.56, P = .089), atrial tachycardia (OR = 0.48, P = .005), ventricular tachycardia (OR = 0.52, P = .04), and atrioventricular block (OR = 0.47, P = .03). The effect of magnesium on reducing the odds of occurrence of postoperative arrhythmias did not differ between 25 mg/kg versus 50 mg/kg. CONCLUSIONS: As many as one third of our patients undergoing congenital heart surgery had postoperative arrhythmias. Use of intraoperative magnesium was associated with a reduction in the odds of occurrence of all postoperative arrhythmias. Our results do not provide evidence that a greater dose of magnesium is associated with greater arrhythmia risk reduction. Despite the intraoperative use of magnesium, there continued to be a high residual incidence of postoperative arrhythmias, raising the question for studying new or additional agents.
OBJECTIVES:Postoperative arrhythmias are common in children undergoing congenital heart surgery. We evaluated whether intraoperative administration of magnesium was associated with a reduced occurrence of specific postoperative arrhythmias, as has been described previously, or had a broader effect on multiple arrhythmia types, and whether there existed a dose-effect of intraoperative magnesium. METHODS: We used a historical prospective observational cohort study. Propensity score matching using logistic regression was applied to establish similar populations of treatment groups balanced on 5 important covariates. RESULTS: Based on propensity score-matched groups, magnesium 50 mg/kg administration was associated with a reduced odds of occurrence of postoperative arrhythmias: any arrhythmia (odds ratio [OR] = 0.50, P < .001), junctional ectopic tachycardia (OR = 0.56, P = .004), accelerated junctional rhythm (OR = 0.56, P = .089), atrial tachycardia (OR = 0.48, P = .005), ventricular tachycardia (OR = 0.52, P = .04), and atrioventricular block (OR = 0.47, P = .03). The effect of magnesium on reducing the odds of occurrence of postoperative arrhythmias did not differ between 25 mg/kg versus 50 mg/kg. CONCLUSIONS: As many as one third of our patients undergoing congenital heart surgery had postoperative arrhythmias. Use of intraoperative magnesium was associated with a reduction in the odds of occurrence of all postoperative arrhythmias. Our results do not provide evidence that a greater dose of magnesium is associated with greater arrhythmia risk reduction. Despite the intraoperative use of magnesium, there continued to be a high residual incidence of postoperative arrhythmias, raising the question for studying new or additional agents.