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Query: UMLS:C0036572 (seizures)
 80,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Magnesium sulfate is currently being used in obstetric practice for either eclamptic seizure prophylaxis or for tocolysis, in some countries. Evidence for its use in preeclampsia is credible, whereas the evidence for its use as a tocolytic is limited, if not absent. Of interest, the findings of two epidemiologic studies have suggested a third possible use for antenatal pharmacologic magnesium sulfate, namely, as a neuroprotectant against the later development of cerebral palsy in the newborn. In support of this hypothesis are laboratory data, much of which have to do with the modulation of cellular membrane receptors. Unfortunately, during the Magnesium and Neurologic Endpoints Trial (MagNET), while attempting to confirm the neuroprotective effect of magnesium sulfate, the occurrence of excess total pediatric mortality in those children exposed to magnesium led to early termination of the trial. Nonetheless, despite the alarming findings in MagNET, it is conceivable that exposures to doses of magnesium sulfate less than those often used for aggressive tocolysis may be neuroprotective without being lethal. Other randomized controlled trials now underway may answer this important question.
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PMID:An overview of the possible relationship between antenatal pharmacologic magnesium and cerebral palsy. 1103 98

Magnesium sulfate therapy, standard in preventing seizures in preeclampsia, is under active investigation as a neuroprotective agent. The authors studied the effect of magnesium as a cerebral vasodilator by measuring the cerebral blood flow velocity (CBFV) response to a 5g intravenous bolus of MgSO4 compared with a saline placebo after subarachnoid hemorrhage (SAH). Transcranial Doppler ultrasonography of the middle cerebral artery (MCA) was measured after each infusion. Patients were studied up to three times after SAH at prescribed time intervals. Fourteen patients (11 women, 3 men; mean age 58 years) underwent 29 studies. All patients underwent hypertensive, hypervolemic therapy. Four patients developed cerebral vasospasm. Doubling serum magnesium levels did not affect MCA CBFV but slightly lowered mean arterial blood pressure and systemic vascular resistance. Intravenous magnesium bolus did not reduce elevated CBFV in the subset of SAH patients with clinical vasospasm. The role of magnesium sulfate as a cerebral vasodilator in patients with SAH requires further study.
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PMID:Cerebral blood flow velocity response to magnesium sulfate in patients after subarachnoid hemorrhage. 1142 93

Gestational hypertension and preeclampsia are common disorders during pregnancy, with the majority of cases developing at or near term. The development of mild hypertension or preeclampsia at or near term is associated with minimal maternal and neonatal morbidities. In contrast, the onset of severe gestational hypertension and/or severe preeclampsia before 35 weeks' gestation is associated with significant maternal and perinatal complications. Women with diagnosed gestational hypertension-preeclampsia require close evaluation of maternal and fetal conditions for the duration of pregnancy, and those with severe disease should be managed in-hospital. The decision between delivery and expectant management depends on fetal gestational age, fetal status, and severity of maternal condition at time of evaluation. Expectant management is possible in a select group of women with severe preeclampsia before 32 weeks' gestation. Steroids are effective in reducing neonatal mortality and morbidity when administered to those with severe disease between 24 and 34 weeks' gestation. Magnesium sulfate should be used during labor and for at least 24 hours postpartum to prevent seizures in all women with severe disease. There is an urgent need to conduct randomized trials to determine the efficacy and safety of antihypertensive drugs in women with mild hypertension-preeclampsia. There is also a need to conduct a randomized trial to determine the benefits and risks of magnesium sulfate during labor and postpartum in women with mild preeclampsia.
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PMID:Diagnosis and management of gestational hypertension and preeclampsia. 1285 Jun 27

Magnesium sulfate is widely used to prevent seizures in pregnant women with hypertension. The aim of this study was to examine the inhibitory mechanisms of magnesium sulfate in platelet aggregation in vitro. In this study, magnesium sulfate concentration-dependently (0.6-3.0 mM) inhibited platelet aggregation in human platelets stimulated by agonists. Magnesium sulfate (1.5 and 3.0 mM) also concentration-dependently inhibited phosphoinositide breakdown and intracellular Ca+2 mobilization in human platelets stimulated by thrombin. Rapid phosphorylation of a platelet protein of M(r) 47,000 (P47), a marker of protein kinase C activation, was triggered by phorbol-12-13-dibutyrate (PDBu, 50 nM). This phosphorylation was markedly inhibited by magnesium sulfate (3.0 mM). Magnesium sulfate (1.5 and 3.0 mM) further inhibited PDBu-stimulated platelet aggregation in human platelets. The thrombin-evoked increase in pHi was markedly inhibited in the presence of magnesium sulfate (3.0 mM). In conclusion, these results indicate that the antiplatelet activity of magnesium sulfate may be involved in the following two pathways: (1) Magnesium sulfate may inhibit the activation of protein kinase C, followed by inhibition of phosphoinositide breakdown and intracellular Ca+2 mobilization, thereby leading to inhibition of the phosphorylation of P47. (2) On the other hand, magnesium sulfate inhibits the Na+/H+ exchanger, leading to reduced intracellular Ca+2 mobilization, and ultimately to inhibition of platelet aggregation and the ATP-release reaction.
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PMID:Involvement of the antiplatelet activity of magnesium sulfate in suppression of protein kinase C and the Na+/H+ exchanger. 1473 Feb 6

Magnesium sulfate is commonly used in obstetrical practice both as seizure prophylaxis in women with preeclampsia, as well as to inhibit preterm labor contractions. However, despite (and perhaps because of) years of use and provider familiarity, the administration of magnesium sulfate occasionally results in accidental overdose and patient harm. Fortunately, in most instances when potentially fatal amounts of magnesium sulfate are given, the error is recognized before permanent adverse outcomes occur. Nevertheless, a significant and sometimes unappreciated risk of harm to mothers and babies continues to exist. Intravenous magnesium sulfate treatment has become routine practice in obstetrics, but this does not lessen the vigilance required for safe care for mothers and babies. Implementation of the recommendations provided in this article will promote patient safety and decrease the likelihood of an accidental overdose, as well as increase the chances of identifying an error before a significant adverse outcome occurs.
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PMID:Obstetrical accidents involving intravenous magnesium sulfate: recommendations to promote patient safety. 1577 15

As the understanding for the mechanism of absorption and metabolism has not been clarified adequately, a lot of works about these issues are still carrying on. Changes in maternal blood and intracellular magnesium concentration during the early stage of pregnancy suggest magnesium may play important roles around the period of implantation. Alternation in absorption of the mineral from colon, in levels of maternal blood and those of intracellular magnesium, or in urinary excretion of magnesium during pregnancy suggest that contents of magnesium in the whole maternal body tend to be decreased with the course of pregnancy. On the other hand, in preeclamptic women lack of magnesium is existed showing a pathological level compared to normal pregnant women. The magnesium deficiency is speculated to have a relation with vascular hypertonus or eclamptic seizures. Magnesium sulfate is frequently used for first choice drug, as it is effective to improve the hypertension of preeclampsia, to prevent or to cure the seizures of eclampsia. The administration of magnesium sulfate to preeclamtic women is reasonable to improve magnesium deficiency, which may be one of pathophysiological aspects of preeclampsia.
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PMID:[Toxemie of pregnancy and magnesium]. 1569 59

Preeclampsia, a serious hypertensive complication of pregnancy characterized by new-onset hypertension and proteinuria after midpregnancy, is a multisystem disorder that often involves the central nervous system. Neurologic signs and symptoms include hyperreflexia, headaches, visual disturbance, seizures, and cerebral hemorrhage. Eclampsia-new-onset seizures in the setting of preeclampsia-usually occurs before or within 48 hours of delivery, but can present as late as 1 month postpartum (late postpartum eclampsia). Magnesium sulfate is the drug of choice to prevent and treat eclampsia, a recommendation validated through large, randomized, and placebo-controlled trials. This review describes the pathogenesis, clinical features, and treatment of eclampsia, focusing on recent observations regarding roles of circulating antiangiogenic factors in the pathogenesis of the neurologic complications of eclampsia.
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PMID:Advances in the understanding of eclampsia. 1862 61

The National High Blood Pressure Education Program Working Group on High Blood Pressure in Pregnancy has defined four categories of hypertension in pregnancy: chronic hypertension, gestational hypertension, preeclampsia, and preeclampsia superimposed on chronic hypertension. A maternal blood pressure measurement of 140/90 mm Hg or greater on two occasions before 20 weeks of gestation indicates chronic hypertension. Pharmacologic treatment is needed to prevent maternal end-organ damage from severely elevated blood pressure (150 to 180/100 to 110 mm Hg); treatment of mild to moderate chronic hypertension does not improve neonatal outcomes or prevent superimposed preeclampsia. Gestational hypertension is a provisional diagnosis for women with new-onset, nonproteinuric hypertension after 20 weeks of gestation; many of these women are eventually diagnosed with preeclampsia or chronic hypertension. Preeclampsia is the development of new-onset hypertension with proteinuria after 20 weeks of gestation. Adverse pregnancy outcomes related to severe preeclampsia are caused primarily by the need for preterm delivery. HELLP (i.e., hemolysis, elevated liver enzymes, and low platelet count) syndrome is a form of severe preeclampsia with high rates of neonatal and maternal morbidity. Magnesium sulfate is the drug of choice to prevent and treat eclampsia. The use of magnesium sulfate for seizure prophylaxis in women with mild preeclampsia is controversial because of the low incidence of seizures in this population.
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PMID:Hypertensive disorders of pregnancy. 1864 16

Over half a million women die each year from pregnancy related causes, 99% in low and middle income countries. In many low income countries, complications of pregnancy and childbirth are the leading cause of death amongst women of reproductive years. The Millennium Development Goals have placed maternal health at the core of the struggle against poverty and inequality, as a matter of human rights. Ten percent of women have high blood pressure during pregnancy, and preeclampsia complicates 2% to 8% of pregnancies. Preeclampsia can lead to problems in the liver, kidneys, brain and the clotting system. Risks for the baby include poor growth and prematurity. Although outcome is often good, preeclampsia can be devastating and life threatening. Overall, 10% to 15% of direct maternal deaths are associated with preeclampsia and eclampsia. Where maternal mortality is high, most of deaths are attributable to eclampsia, rather than preeclampsia. Perinatal mortality is high following preeclampsia, and even higher following eclampsia. In low and middle income countries many public hospitals have limited access to neonatal intensive care, and so the mortality and morbidity is likely to be considerably higher than in settings where such facilities are available. The only interventions shown to prevent preeclampsia are antiplatelet agents, primarily low dose aspirin, and calcium supplementation. Treatment is largely symptomatic. Antihypertensive drugs are mandatory for very high blood pressure. Plasma volume expansion, corticosteroids and antioxidant agents have been suggested for severe preeclampsia, but trials to date have not shown benefit. Optimal timing for delivery of women with severe preeclampsia before 32 to 34 weeks' gestation remains a dilemma. Magnesium sulfate can prevent and control eclamptic seizures. For preeclampsia, it more than halves the risk of eclampsia (number needed to treat 100, 95% confidence interval 50 to 100) and probably reduces the risk of maternal death. A quarter of women have side effects, primarily flushing. With clinical monitoring serious adverse effects are rare. Magnesium sulfate is the anticonvulsant of choice for treating eclampsia; more effective than diazepam, phenytoin, or lytic cocktail. Although it is a low cost effective treatment, magnesium sulfate is not available in all low and middle income countries; scaling up its use for eclampsia and severe preeclampsia will contribute to achieving the Millennium Development Goals.
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PMID:The global impact of pre-eclampsia and eclampsia. 1946 2

Magnesium sulfate, a biologically potent compound, given sometimes in extraordinarily high doses, is among the most commonly used pharmaceuticals in American obstetric practice. Although most clinicians are in accord regarding its value for seizure prophylaxis in the setting of preeclampsia, such unanimity is not the case regarding its role in preterm labor. Credible scientific data indicate not only a lack of efficacy, but also toxicity to susceptible fetuses when magnesium sulfate is used in the high dosages found in tocolysis. In apparent contrast, three recent clinical trials, although individually inconclusive, provide data from which a very recent meta-analysis affirms a potential role for magnesium sulfate in prophylaxis against fetal neurologic injury. Comparing outcomes from these trials, with attention to dosage, relationships are revealed that unify observations previously regarded as conflicting: Magnesium sulfate indeed may have both neuroprotective and fetal toxic effects. The better, and safer, neuroprotection seems to occur at comparatively low antenatal doses (perhaps in a range between 4 g and 10.5 g), whereas increasing dosages exceed a "therapeutic window" whereby, as with most drugs, toxic sequelae begin to accrue.
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PMID:Contemporary usage of obstetric magnesium sulfate: indication, contraindication, and relevance of dose. 2002 61


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