Department of Obstetrics and Gynecology, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg, Sweden.
Center of Perinatal Medicine and Health, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Acta Obstet Gynecol Scand. 2022 Aug;101(8):856-861. doi: 10.1111/aogs.14372. Epub 2022 May 2.
Magnesium sulfate is used world-wide to treat pregnant women at imminent risk of preterm delivery in order to protect the brain of the premature infant. Previous research has shown that magnesium sulfate decreases the risk of cerebral palsy by ~30% in infants born preterm. Despite this, the dosage required for optimal neuroprotection remains unknown. We aimed to investigate whether 6 g magnesium sulfate given as a single bolus dose was tolerable for the women and infants and whether the desired target concentration in the mother's blood was reached and non-toxic level in the infant could be ensured.
In total, 49 women who were at risk of delivery prior to 32 weeks of gestation were recruited. They received a bolus dose of 6 g magnesium sulfate intravenously between 1 and 24 h prior to giving birth and were closely monitored during and after infusion. Blood samples from the patients were analyzed at different time-points (20-30 min after start of infusion, 1, 2, 6 and 24 h) post-administration. Blood samples from the umbilical cord were also taken directly after birth to assess the concentration of magnesium in the infant.
None of the women who received magnesium sulfate reached serum magnesium concentrations >3.3 mmol/L. In all, 72% of the women showed serum magnesium levels within the therapeutic interval (2.0-3.5 mmol/L) and no adverse events were observed during the infusion. The serum magnesium levels in the mothers declined to pre-bolus-levels within 24 h after delivery. Serum magnesium levels in the umbilical cord samples ranged from 0.87 to 1.4 mmol/L, which means that all but two were within the normal expected range for a newborn premature infant.
A bolus dose of 6 g magnesium sulfate was well tolerated and without any serious side effects in either mother or infant. Most of our women reached the targeted concentration range of serum magnesium levels after infusion was completed. Their infants had magnesium levels within acceptable levels, regardless of gestational week or mother's body mass index.
硫酸镁在全世界范围内用于治疗有早产风险的孕妇，以保护早产儿的大脑。先前的研究表明，镁盐可将早产儿脑瘫的风险降低约 30%。尽管如此，仍不清楚最佳神经保护所需的剂量。我们旨在研究单次推注 6 克硫酸镁是否可耐受，母亲的血液中是否达到了所需的目标浓度，并且婴儿是否能达到无毒水平。
总共招募了 49 名在 32 周前有分娩风险的孕妇。在分娩前 1 至 24 小时内，她们接受了 6 克硫酸镁静脉推注，并在输注期间和之后进行了密切监测。在给药后不同时间点（输注开始后 20-30 分钟，1、2、6 和 24 小时）从患者中采集血样。在分娩后直接从脐带中采集血样，以评估婴儿血液中镁的浓度。
没有接受硫酸镁的妇女达到血清镁浓度> 3.3mmol/L。在所有妇女中，72%的妇女的血清镁水平处于治疗范围内（2.0-3.5mmol/L），并且在输注过程中没有观察到不良反应。分娩后 24 小时内，母亲的血清镁水平降至推注前水平。脐带样本中的血清镁水平范围为 0.87 至 1.4mmol/L，这意味着除了两个样本外，其余样本均处于新生儿早产儿的正常预期范围内。
6 克硫酸镁的推注剂量在母亲和婴儿中均耐受良好，无任何严重副作用。输注完成后，我们大多数妇女达到了目标血清镁浓度范围。无论胎龄或母亲的体重指数如何，婴儿的镁水平均处于可接受的水平。
