DO IONIZED MAGNESIUM LEVELS PREDICT CLINICAL EFFECTS BETTER THAN TOTAL MAGNESIS

离子镁水平比总镁水平更能预测临床效果吗

• 批准号: 7606211
• 负责人: Michael Glenn Ross
• 金额: $ 0.44万
• 依托单位: LUNDQUIST INSTITUTE FOR BIOMEDICAL INNOVATION AT HARBOR-UCLA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-02-01 至 2007-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7606211
• 关键词: Age; Arrhythmia; Blood; Blood Pressure; Bolus Infusion; Catheters; Cervical; Clinical; Collection; Computer Retrieval of Information on Scientific Projects Database; Condition; Creatinine; Depth; Development; Diagnosis; Discipline of obstetrics; Drowsiness; Funding; Future; Grant; Hour; Hypersensitivity; Hypertension induced by pregnancy; Individual; Infusion procedures; Inorganic Sulfates; Institution; Intervention; Intervention Studies; Intravenous; Kidney Diseases; Long-Term Effects; Magnesium; Magnesium Sulfate; Measures; Medical; Monitor; Myasthenia Gravis; Neural Conduction; Nursing Staff; Oxygen; Patient currently pregnant; Patients; Physicians; Pre-Eclampsia; Premature Labor; Proteins; Proteinuria; Protocols documentation; Purpose; Range; Rate; Recording of previous events; Research; Research Personnel; Resources; Risk; Running; Serum; Serum Calcium Level; Shock; Site; Source; Standards of Weights and Measures; Structure of ulnar nerve; Tendon Reflex; Testing; Therapeutic; United States National Institutes of Health; Unspecified or Sulfate Ion Sulfates; Upper Limit of Normal; Urine; Uterine Contraction; Woman; child bearing; clinical effect; dosage; experience; falls; improved; pregnancy hypertension; respiratory

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Intravenous magnesium sulfate (MgS04) is widely used in obstetrics for the treatment of both preterm labor (PTL) and pregnancy induced hypertension (PI H). However, there is little information regarding optimal dosage and therapeutic levels, as it is not possible to correlate Mg levels with changes in uterine contractions or blood pressure. the form of magnesium commonly measured is total magnesium (tMg). We recently demonstrated that levels of the active form of magnesium, free or ionized (iMg) do not correlate well with tMglevels. The purpose of this study is to determine whether iMg concentrations correlate better than tMg with changes in nerve conduction. Women of child bearing potential, over the age of 18, seen at this center, are eligible for participation in this study. 10 pregnant patients requiring Mg for preterm labor and 10 pregnant patients requiring Mg for pregnancy hypertension will be studied. An indwelling intravenous catheter will be placed for all blood draws. Blood will be drawn for serum creatinine levels before initiation of Mg treatment. Subjects will be excluded for creatinine levels greater than 1.2mg/dL (Harbor¿UCLA upper limit of normal). Patients with renal disease, history of hypersensitivity to magnesium, and history of a medical condition which would be impacted by the magnesium (such as myasthenia gravis) or history of a cardio¿pulmonary condition, will also be excluded from the study. Each subject will have a baseline blood level to determine basal magnesium (tMg and iMg) levels. Magnesium levels will.1 also be determined hourly for the duration of the study. Serum calcium levels will be determined along with magnesium. At hourly intervals throughout the infusion and post infusion periods, magnesium levels (total and ionized) will be obtained, and ulnar nerve conduction studies (NCS) will be performed. The NCS will consist of a total of ten electrical shocks. These will be repeated at three hOurly intervals for a total of 30 shocks. These shocks are mildly uncomfortable to most people. During Mg infusion, all subjects will have respiratory rate, blood pressure and uterine activity logged every hour. Deep tendon reflexes (DTR) will also be tested at each blood determination to assess magnesium effects. Magnesium infusions will be discontinued if oxygen saturation falls below 92% or by 5%, if cardiac arrhythmias occur, for development of somnolence, or from the loss of DTRs. All patients will be closely monitored as well as clinically treated and observed by nursing staff and physicians on duty. The magnesium infusion will run thru a separate IV access site. All pregnant patients in this study will be receiving required therapeutic magnesium sulfate for preterm labor or pregnancy hypertension. All Mg infusions will be administered as an initial bolus of 4-6 grams, given over twenty to thirty minutes. This will be followed by an infusion of 2-3 gm/hr for a total of four hours. After the four hours the magnesium sulfate will be continued as clinically indicated. Risks to patients appear to be minimal for long-term effects. Most individuals will experience some discomfort ranging from mild to severe. There is no benefit to individuals participating in this study. All patients participating in this study will be receiving Mg-sulfate as clinically indicated for preterm labor or preeclampsia per standard clinical criteria despite whether or not they continue with the study. Magnesium will be administered per standard protocol for preterm labor and preclampsia. In this study Mg is the research intervention being studied but it is also the standard clinical intervention for these conditions. The clinical criteria for diagnosis preterm labor are uterine contractions and cervical change. The clinical criteria for preeclampsia are blood pressure> 140/90 and proteinuria (24 hour urine collection greater than 300 mg or 1 + protein on urine dipstick). Mg is the treatment and it is administered in the same manner whether or not the patient is in the study or does not participate in the study. There may be benefits to future patients, if the results of the study allow safer use of magnesium in clinical practice. This would clinically improve monitoring of the therapeutic levels in patients and decrease toxic levels of magnesium sulfate.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以出现在其他 CRISP 条目中 列出的机构是。 对于中心来说，它不一定是研究者的机构。 静脉注射硫酸镁 (MgSO4) 广泛用于产科治疗早产 (PTL) 和妊娠高血压 (PI H)，但是，关于最佳剂量和治疗水平的信息很少，因为不可能相互关联。镁水平随子宫收缩或血压的变化而变化，通常测量的镁形式是总镁 (tMg)。我们最近证明了游离或离子镁 (iMg) 的活性形式的水平。与 tMg 水平相关性不佳。本研究的目的是确定 iMg 浓度是否比 tMg 浓度与神经传导变化的相关性更好。 在该中心就诊的 18 岁以上有生育潜力的妇女有资格参与这项研究，其中 10 名因早产而需要镁的孕妇和 10 名因妊娠高血压而需要镁的孕妇将接受留置静脉导管的研究。在开始 Mg 治疗之前，将进行所有抽血以测定血清肌酐水平。肌酐水平高于 1.2mg/dL 的受试者将被排除。 （Harbor - UCLA 正常上限）患有肾脏疾病、对镁过敏史以及受镁影响的医疗状况（例如重症肌无力）或心脏病史的患者。肺部状况，也将被排除在研究之外。每个受试者将有一个基线血液水平来确定基础镁（tMg 和 iMg）水平。在研究期间，还将每小时确定一次血清钙水平。在整个输注期间和输注后期间，每小时间隔一次，将获得镁水平（总镁和离子镁），并且将进行尺神经传导研究（NCS）。每隔三小时重复 10 次电击，总共 30 次，这些电击对大多数人来说都会有点不舒服。 在镁输注期间，所有受试者每小时都会记录呼吸频率、血压和子宫活动，每次血液测定时也会测试深腱反射 (DTR)，以评估镁的影响。如果氧饱和度低于 92，则将停止镁输注。如果出现心律失常、嗜睡或 DTR 丧失，则减少 % 或 5%。 所有患者都将受到密切监测以及临床治疗和护理观察。值班的工作人员和医生将通过单独的静脉注射部位进行镁输注。 本研究中的所有怀孕患者都将接受治疗早产或妊娠高血压所需的硫酸镁。所有镁输注均将以 4-6 克的初始推注形式给药，随后输注 20 至 30 分钟。 2-3克/小时，总共四小时。四小时后，将根据临床指示继续使用硫酸镁。 长期影响对患者的风险似乎很小。参与本研究的所有患者都将接受临床上的硫酸镁治疗。根据标准临床标准，表明镁用于早产或先兆子痫，无论是否继续根据早产和先兆子痫的标准方案施用镁。诊断早产的临床标准是子宫收缩和宫颈改变。先兆子痫的临床标准是血压> 140/90 和蛋白尿（24 小时尿液收集量大于 300 毫克或尿试纸检测到 1 + 蛋白）。镁是一种治疗方法，无论患者是否参与研究，其给药方式均相同。 如果研究结果允许在临床实践中更安全地使用镁，这可能会给未来的患者带来好处，这将在临床上改善对患者治疗水平的监测并降低硫酸镁的毒性水平。