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.

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 静脉内硫酸镁（MgS 〇 4）广泛用于产科治疗早产（PTL）和妊娠高血压（PIH）。然而，关于最佳剂量和治疗水平的信息很少，因为不可能将镁水平与子宫收缩或血压的变化相关联。通常测量的镁的形式是总镁（tMg）。我们最近证明，水平的活性形式的镁，游离或离子化（iMg）不相关，以及与tMg水平。本研究的目的是确定iMg浓度与神经传导变化的相关性是否优于tMg。 在该中心就诊的18岁以上有生育能力的女性有资格参与本研究。将研究10例需要Mg治疗早产的妊娠患者和10例需要Mg治疗妊娠高血压的妊娠患者。所有抽血均将放置留置静脉导管。在开始镁治疗前，将采集血液用于测定血清肌酐水平。肌酐水平大于1.2 mg/dL（Harbor <$UCLA正常值上限）的受试者将被排除。患有肾脏疾病、有镁过敏史、有可能受镁影响的疾病史（如重症肌无力）或心肺疾病史的患者也将从研究中排除。每例受试者将有一个基线血液水平，以确定基础镁（tMg和iMg）水平。在研究期间，还将每小时测定一次镁水平。将沿着测定血清钙水平和镁水平。在整个输注期间和输注后每小时采集一次镁水平（总镁和离子镁），并进行尺神经传导研究（NCS）。NCS将包括总共10次电击。每隔三小时重复一次，总共30次电击。这些冲击对大多数人来说都有点不舒服。 在镁输注期间，所有受试者将每小时记录一次呼吸频率、血压和子宫活动。还将在每次血液测定时检测深腱反射（DTR），以评估镁的影响。如果氧饱和福尔斯92%或低于5%，如果发生心律失常，出现嗜睡或DTR丧失，将停止镁输注。所有患者将受到密切监测，并由护理人员和值班医生进行临床治疗和观察。镁输注将通过单独的IV穿刺部位进行。 本研究中的所有妊娠患者将接受所需的治疗性硫酸镁治疗早产或妊娠高血压。所有镁输注将以4-6 g的初始推注给药，在20 - 30分钟内给药。随后以2-3 gm/hr输注，共4小时。四小时后，将根据临床指征继续使用硫酸镁。 长期影响对患者的风险似乎很小。大多数人会经历一些从轻微到严重的不适。参与本研究的个体无获益。参与本研究的所有患者将根据标准临床标准接受临床指征为早产或先兆子痫的硫酸镁治疗，无论他们是否继续参与研究。将按照早产和先兆子痫的标准方案给予镁。在这项研究中，镁是正在研究的研究干预，但它也是这些条件的标准临床干预。临床诊断早产的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小时尿收集大于300 mg或尿试纸上的1 +蛋白）。镁是治疗，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，则可能对未来的患者有益。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。