Department of Pharmacy, University of North Carolina Hospitals & Clinics, 101 Manning Drive, CB #7600, Chapel Hill, NC 27514, USA.
Am J Health Syst Pharm. 2012 Jul 15;69(14):1212-7. doi: 10.2146/ajhp110574.
The results of an investigation of serum magnesium concentrations (SMCs) after i.v. versus oral delivery of magnesium in cardiovascular critical care are presented.
A retrospective case review was conducted to compare the net gain of magnesium after i.v. (n = 188) or oral (n = 164) magnesium therapy for the prevention of ventricular fibrillation and arrhythmias in patients hospitalized for serious cardiovascular disorders, as determined by assessing SMCs. The primary study outcome was the change from baseline SMC values 6-24 hours after the completion of magnesium courses; secondary outcomes included the impact of renal impairment, concomitant medication use, and other clinical variables on SMC changes.
Although consistent elevations in SMC were produced by oral magnesium delivery, i.v. administration resulted in greater and more rapid elevations relative to baseline SMC. The degree of change in SMC was significantly influenced by the timing of SMC measurement after a magnesium course, by renal function, and by concomitant use of i.v. loop diuretics.
A comparison of 24-hour courses of magnesium replacement therapy showed that magnesium sulfate 2 g i.v. was associated with larger changes in SMC than magnesium oxide 800, 1200, or 1600 mg orally when the baseline SMC was 1.4-1.8 mg/dL. At baseline SMCs of 1.4-1.8 mg/dL, oral magnesium oxide provided a consistent median increase in SMC of 0.1 mg/dL. The change in the number of bowel movements did not differ significantly between courses of i.v. magnesium sulfate and oral magnesium oxide.
介绍静脉与口服给予镁在心血管重症监护中对血清镁浓度（SMCs）的影响。
对静脉（n = 188）和口服（n = 164）镁治疗预防严重心血管疾病住院患者室性纤颤和心律失常的病例进行回顾性分析，通过评估 SMCs 比较静脉和口服镁治疗后 SMC 的净增加量。主要研究结果是镁疗程结束后 6-24 小时 SMC 值与基线值的变化；次要研究结果包括肾功能不全、合并用药及其他临床变量对 SMC 变化的影响。
尽管口服镁治疗可使 SMC 持续升高，但静脉给药与基线 SMC 相比，升高幅度更大且更迅速。SMC 变化程度受镁疗程后 SMC 测量时间、肾功能和静脉袢利尿剂合并使用的影响。
对 24 小时镁替代治疗疗程的比较显示，当基线 SMC 为 1.4-1.8 mg/dL 时，静脉给予硫酸镁 2 g 与口服氧化镁 800、1200 或 1600 mg 相比，更能显著改变 SMC。在基线 SMC 为 1.4-1.8 mg/dL 时，口服氧化镁使 SMC 中位数持续增加 0.1 mg/dL。静脉给予硫酸镁与口服氧化镁疗程之间的排便次数变化无显著差异。
