Aali Bibi Shahnaz, Khazaeli Payam, Ghasemi Fatemeh
Department of Obstetrics and Gynecology, Physiology Research Center, Kerman University of Medical Sciences, Kerman, Iran.
J Obstet Gynaecol Res. 2007 Apr;33(2):138-43. doi: 10.1111/j.1447-0756.2007.00508.x.
As ionized magnesium is the active form of magnesium and exerts a therapeutic effect, the present study was performed to determine the levels and correlations between ionized and total magnesium under baseline and therapeutic conditions in patients with severe preeclampsia and eclampsia receiving magnesium sulfate.
Fifty singleton patients with severe preeclampsia received a loading dose of 4 g of magnesium sulfate, followed by 2 g per hour as maintenance dose until 24 h after delivery, or 24 h after the last seizure in case of postpartum convulsions. Serial blood samples were taken before magnesium sulfate infusion, 30 min and 240 min after the initiation of the infusion and 4 h after the discontinuation of the drug. Data were analyzed by repeated measure ANOVA and paired t-test.
Baseline levels of total and ionized magnesium were 2.4+/-0.6 mEq/L and 1.3+/-0.5 mEq/L (mean+/-SD), respectively. Putative level of 4 mEq/L of total magnesium was not obtained in up to 42% of patients during the treatment. There was not any significant correlation between the two forms of magnesium under baseline and therapeutic conditions.
Despite the effectiveness of the standard regimen of magnesium sulfate in the treatment and prevention of eclamptic seizures, it can not provide the proposed therapeutic level of magnesium in all patients. With respect to the lack of correlation between ionized and total magnesium, further studies are necessary to investigate the superiority of measurement of ionized, rather than total magnesium, for titration of therapeutic magnesium sulfate infusion.
由于离子镁是镁的活性形式并具有治疗作用，本研究旨在确定接受硫酸镁治疗的重度子痫前期和子痫患者在基线和治疗条件下离子镁和总镁的水平及其相关性。
50名单胎重度子痫前期患者接受4g硫酸镁负荷剂量，随后以每小时2g作为维持剂量，直至分娩后24小时，或产后惊厥时最后一次惊厥后24小时。在输注硫酸镁前、输注开始后30分钟和240分钟以及停药后4小时采集系列血样。数据采用重复测量方差分析和配对t检验进行分析。
总镁和离子镁的基线水平分别为2.4±0.6mEq/L和1.3±0.5mEq/L（均值±标准差）。治疗期间高达42%的患者未达到总镁4mEq/L的假定水平。在基线和治疗条件下，两种形式的镁之间均无显著相关性。
尽管硫酸镁标准方案在治疗和预防子痫惊厥方面有效，但它不能使所有患者达到建议的镁治疗水平。鉴于离子镁和总镁之间缺乏相关性，有必要进一步研究以探讨测量离子镁而非总镁在滴定硫酸镁治疗性输注方面的优越性。
