Intravenous Magnesium Therapy Research Articles

Fetal Long QT Syndrome - Challenges in Perinatal Management: A Review and Case Report. Induction of Labor and Vaginal Birth Under Continuous Magnesium Therapy.

Congenital LQTS is an often undetected inherited cardiac channel dysfunction and can be a reason for intrauterine fetal demise. It can present in utero as CTG and ultrasound abnormalities, i. e., bradycardia, ventricular tachycardia, or fetal hydrops. Diagnosis is made by CTG, echocardiography, or fMCG. Intrauterine therapy with a ß blocker and i. v. magnesium should be started. Our objective was to examine the current knowledge about diagnosis and treatment of LQTS and in particular to highlight the opportunity of vaginal birth under continuous intravenous magnesium therapy. Therefore, a thorough MEDLINE and Google Scholar search was conducted. Randomized controlled trials, meta-analyses, prospective and retrospective cohort trials, and case reports were considered. We showed the possibility of vaginal delivery under continuous magnesium therapy in a case of suspected fetal LQTS. A stepwise concept for diagnosis, monitoring, and peripartum management in low, intermediate, and high risk cases of fetal LQTS is presented. If risk is low or intermediate, a vaginal delivery under continuous monitoring is reasonable. Induction of labor at term should be evaluated.

Association Between Intravenous Magnesium Therapy in the Emergency Department and Subsequent Hospitalization Among Pediatric Patients With Refractory Acute Asthma

Despite guidelines recommending administration of intravenous (IV) magnesium sulfate for refractory pediatric asthma, the number of asthma-related hospitalizations has remained stable, and IV magnesium therapy is independently associated with hospitalization. To examine the association between IV magnesium therapy administered in the emergency department (ED) and subsequent hospitalization among pediatric patients with refractory acute asthma after adjustment for patient-level variables. This post hoc secondary analysis of a double-blind randomized clinical trial of children with acute asthma treated from September 26, 2011, to November 19, 2019, at 7 Canadian tertiary care pediatric EDs was conducted between September and November 2020. In the randomized clinical trial, 816 otherwise healthy children aged 2 to 17 years with Pediatric Respiratory Assessment Measure (PRAM) scores of 5 points or higher after initial therapy with systemic corticosteroids and inhaled albuterol with ipratropium bromide were randomly assigned to 3 nebulized treatments of albuterol plus either magnesium sulfate or 5.5% saline placebo. Intravenous magnesium sulfate therapy (40-75 mg/kg). The association between IV magnesium therapy in the ED and subsequent hospitalization for asthma was assessed using multivariable logistic regression analysis. Analyses were adjusted for year epoch at enrollment, receipt of IV magnesium, PRAM score after initial therapy and at ED disposition, age, sex, duration of respiratory distress, previous intensive care unit admission for asthma, hospitalizations for asthma within the past year, atopy, and receipt of oral corticosteroids within 48 hours before arrival in the ED, nebulized magnesium, and additional albuterol after inhaled magnesium or placebo, with site as a random effect. Among the 816 participants, the median age was 5 years (interquartile range, 3-7 years), 517 (63.4%) were boys, and 364 (44.6%) were hospitalized. A total of 215 children (26.3%) received IV magnesium, and 190 (88.4%) of these children were hospitalized compared with 174 of 601 children (29.0%) who did not receive IV magnesium. Multivariable factors associated with hospitalization were IV magnesium receipt from 2011 to 2016 (odds ratio [OR], 22.67; 95% CI, 6.26-82.06; P < .001) and from 2017 to 2019 (OR, 4.19; 95% CI, 1.99-8.86; P < .001), use of additional albuterol (OR, 5.94; 95% CI, 3.52-10.01; P < .001), and increase in PRAM score at disposition (per 1-U increase: OR, 2.24; 95% CI, 1.89-2.65; P < .001). In children with a disposition PRAM score of 3 or lower, receipt of IV magnesium therapy was associated with hospitalization (OR, 8.52; 95% CI, 2.96-24.41; P < .001). After adjustment for patient-level characteristics, receipt of IV magnesium therapy after initial asthma treatment in the ED was associated with subsequent hospitalization. This association also existed among children with mild asthma at ED disposition. Evidence of a benefit of IV magnesium regarding hospitalization may clarify its use in the treatment of refractory pediatric asthma. ClinicalTrials.gov: NCT01429415.

Characterization of Magnesium Sulfate as an Antiarrhythmic Agent.

BACKGROUND: Recently, intravenous magnesium therapy has been used for the treatment of ventricular arrhythmias, but data to establish a causal link between the electrophysiological properties and the antiarrhythmic actions are lacking. METHODS AND RESULTS: The acute antiarrhythmic effect of magnesium sulfate was assessed using epinephrine-, digitalis-, and coronary ligation-induced canine ventricular arrhythmia models. The intravenous administration of magnesium sulfate (100 mg/kg) reduced the incidence of the ventricular arrhythmias of all models. The antiarrhythmic effect on the epinephrine-induced arrhythmia was potent and long-lasting, while those on the other arrhythmia models were weak and transient. The direct cardiovascular effects were assessed using the canine isolated, blood-perfused sinus node, papillary muscle, and atrioventricular node preparations. The intracoronary administration of magnesium sulfate (0.1-30 mg) suppressed sinoatrial automaticity and ventricular contraction, while it increased atrio-His and His-ventricular conduction time, coronary blood flow, and the duration of monophasic action potential in a dose-dependent manner. The effects on His-ventricular conduction and monophasic action potential duration were less potent compared with the other cardiovascular effects. CONCLUSIONS: These results suggest that magnesium sulfate possesses multiple electrophysiological properties and that the effects related to the calcium channel inhibition may be the most relevant for the antiarrhythmic actions.

The role of magnesium deficiency in cardiovascular and intestinal inflammation.

Hypomagnesemia continues to cause difficult clinical problems, such as significant cardiac arrhythmias where intravenous magnesium therapy can be lifesaving. Nutritional deficiency of magnesium may present with some subtle symptoms such as leg cramps and occasional palpitation. We have investigated dietary-induced magnesium deficiency in rodent models to assess the pathobiology associated with prolonged hypomagnesemia. We found that neuronal sources of the neuropeptide, substance P (SP), contributed to very early prooxidant/proinflammatory changes during Mg deficiency. This neurogenic inflammation is systemic in nature, affecting blood cells, cardiovascular, intestinal, and other tissues, leading to impaired cardiac contractility similar to that seen in patients with heart failure. We have used drugs that block the release of SP from neurons and SP-receptor blockers to prevent some of these pathobiological changes; whereas, blocking SP catabolism enhances inflammation. Our findings emphasize the essential role of this cation in preventing cardiomyopathic changes and intestinal inflammation in a well-studied animal model, and also implicate the need for more appreciation of the potential clinical relevance of optimal magnesium nutrition and therapy.

Magnesium for treating sickle cell disease.

Sickle cell disease is an autosomal recessive inherited haemoglobinopathy which causes painful vaso-occlusive crises due to sickle red blood cell dehydration. Vaso-occlusive crises are common painful events responsible for a variety of clinical complications; overall mortality is increased and life expectancy decreased compared to the general population. Experimental studies suggest that intravenous magnesium has proven to be well-tolerated in individuals hospitalised for the immediate relief of acute (sudden onset) painful crisis and has the potential to decrease the length of hospital stay. Some in vitro studies and open studies of long-term oral magnesium showed promising effect on pain relief but failed to show its efficacy. The studies show that oral magnesium therapy may prevent sickle red blood cell dehydration and prevent recurrent painful episodes. There is a need to access evidence for the impact of oral and intravenous magnesium effect on frequency of pain, length of hospital stay and quality of life. This is an updated version of the review. To evaluate the effects of short-term intravenous magnesium on the length of hospital stay and quality of life in children and adults with sickle cell disease. To determine the effects of long-term oral magnesium therapy on the frequency of painful crises and the quality of life in children and adults with sickle cell disease. We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books.Date of last search of the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register: 03 February 2019.Date of last search of other resources (clinical trials registries): 04 April 2019. We searched for published and unpublished randomized controlled studies of oral or intravenous magnesium compared to placebo or no magnesium. Authors independently assessed the study quality and extracted the data using standard Cochrane methodologies. We included five randomized placebo-controlled studies with a total of 386 participants (aged three to 53 years). Of these, two shorter parallel studies (n = 306) compared intravenous magnesium sulphate to placebo (normal saline) for admission to hospital due to a vaso-occlusive crisis, for which we were able to analyse data. The quality of evidence was moderate for studies in this comparison, mainly due to limitations due to risk of bias and imprecision. Two of the three longer-term studies comparing oral magnesium pidolate to placebo had a cross-over design. The third was a parallel factorial study which compared hydroxyurea and oral magnesium to each other and to placebo over a longer period of time; we only present the comparison of oral magnesium to placebo from this study. The quality of evidence was very low with uncertainty of the estimation.The eight-hourly dose levels in the two studies of intravenous magnesium were different; one used 100 mg/kg while the second used 40 mg/kg. Only one of these studies (n = 104) reported the mean daily pain score while hospitalised (a non-significant difference between groups, moderate quality evidence). The second study (n = 202) reported a number of child- and parent-reported quality of life scores. None of the scores showed any difference between treatment groups (low quality evidence). Data from one study (n = 106) showed no difference in length of stay in hospital between groups (low quality evidence). Both studies reported on adverse events, but not defined by severity as we had planned. One study showed significantly more participants receiving intravenous magnesium experienced warmth at infusion site compared to placebo; there were no differences between groups for other adverse events (low quality evidence).Three studies (n = 80) compared oral magnesium pidolate to placebo. None of them reported data which we were able to analyse. One study (n = 24) reported on the number of painful days and stated there was no difference between two groups (low quality evidence). None of the studies reported on quality of life or length of hospital stay. Two studies (n = 68) reported there were no differences in levels of magnesium in either plasma or red blood cells (moderate quality evidence). Two studies (n = 56) reported adverse events. One reported episodes of mild diarrhoea and headache, all of which resolved without stopping treatment. The second study reported adverse events as gastrointestinal disorders, headache or migraine, upper respiratory infections and rash; which were all evenly distributed across treatment groups (moderate quality evidence). Moderate to low quality evidence showed neither intravenous magnesium and oral magnesium therapy has an effect on reducing painful crisis, length of hospital stay and changing quality of life in treating sickle cell disease. Therefore, no definitive conclusions can be made regarding its clinical benefit. Further randomized controlled studies, perhaps multicentre, are necessary to establish whether intravenous and oral magnesium therapies have any effect on improving the health of people with sickle cell disease.

Magnesium for treating sickle cell disease.

Sickle cell disease is an autosomal recessive inherited haemoglobinopathy which causes painful vaso-occlusive crises due to sickle red blood cell dehydration. Vaso-occlusive crises are common painful events responsible for a variety of clinical complications; overall mortality is increased and life expectancy decreased compared to the general population. Experimental studies suggest that intravenous magnesium has proven to be well-tolerated in individuals hospitalised for the immediate relief of acute (sudden onset) painful crisis and has the potential to decrease the length of hospital stay. Some in vitro studies and open studies of long-term oral magnesium showed promising effect on pain relief but failed to show its efficacy. The studies show that oral magnesium therapy may prevent sickle red blood cell dehydration and prevent recurrent painful episodes. There is a need to access evidence for the impact of oral and intravenous magnesium effect on frequency of pain, length of hospital stay and quality of life. To evaluate the effects of short-term intravenous magnesium on the length of hospital stay and quality of life in children and adults with sickle cell disease. To determine the effects of long-term oral magnesium therapy on the frequency of painful crises and the quality of life in children and adults with sickle cell disease. We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books.Date of last search of the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register: 01 December 2016.Date of last search of other resources (clinical trials registries): 29 March 2017. We searched for published and unpublished randomized controlled studies of oral or intravenous magnesium compared to placebo or no magnesium. Authors independently assessed the study quality and extracted the data using standard Cochrane methodologies. We included five randomized placebo-controlled studies with a total of 386 participants (aged three to 53 years). Two shorter parallel studies (n = 306) compared intravenous magnesium sulphate to placebo (normal saline) for admission to hospital due to a vaso-occlusive crisis, for which we were able to analyse data. The quality of evidence was moderate for studies presenting this comparison mainly due to limitations due to risk of bias and imprecision. Two of the three longer-term studies comparing oral magnesium pidolate to placebo had a cross-over design. The third was a parallel factorial study which compared hydroxyurea and oral magnesium to each other and to placebo over a longer period of time; we only present the comparison of oral magnesium to placebo from this study. The quality of evidence was very low with uncertainty of the estimation.The eight-hourly dose levels in the two studies of intravenous magnesium were different; one used 100 mg/kg while the second used 40 mg/kg. Only one of these studies (n = 104) reported the mean daily pain score while hospitalised (a non-significant difference between groups, moderate quality evidence). The second study (n = 202) reported a number of child- and parent-reported quality of life scores. None of the scores showed any difference between treatment groups (low quality evidence). Data from one study (n = 106) showed no difference in length of stay in hospital between groups (low quality evidence). Both studies reported on adverse events, but not defined by severity as we had planned. One study showed significantly more participants receiving intravenous magnesium experienced warmth at infusion site compared to placebo; there were no differences between groups for other adverse events (low quality evidence).Three studies (n = 80) compared oral magnesium pidolate to placebo. None of them reported data which we were able to analyse. One study (n = 24) reported on the number of painful days and stated there was no difference between two groups (low quality evidence). None of the studies reported on quality of life or length of hospital stay. Two studies (n = 68) reported there were no differences in levels of magnesium in either plasma or red blood cells (moderate quality evidence). Two studies (n = 56) reported adverse events. One reported episodes of mild diarrhoea and headache, all of which resolved without stopping treatment. The second study reported adverse events as gastrointestinal disorders, headache or migraine, upper respiratory infections and rash; which were all evenly distributed across treatment groups (moderate quality evidence). Moderate to low quality evidence showed neither intravenous magnesium and oral magnesium therapy has an effect on reducing painful crisis, length of hospital stay and changing quality of life in treating sickle cell disease. Therefore, no definitive conclusions can be made regarding its clinical benefit. Further randomized controlled studies, perhaps multicentre, are necessary to establish whether intravenous and oral magnesium therapies have any effect on improving the health of people with sickle cell disease.

The Effect of Intravenous Magnesium Therapy on Spinalanaesthesia Produced by Bupivacaine In Pre-Eclamptic Patients

The Effect of Intravenous Magnesium Therapy on Spinalanaesthesia Produced by Bupivacaine In Pre-Eclamptic Patients

Incidence, hemodynamic, and electrical characteristics of spreading depolarization in a swine model are affected by local but not by intravenous application of magnesium

The aim was to characterize the effects of magnesium sulfate, using i.v. bolus and local administration, using intrinsic signal imaging, and on electrocorticographic activity during the induction and propagation of spreading depolarizations in the gyrencephalic porcine brain. Local application of magnesium sulfate led to a complete inhibition of spreading depolarizations. One hour after washing out the topical magnesium sulfate, re-incidence of the spreading depolarizations was observed in 50% of the hemispheres. Those spreading depolarizations showed attenuation in hemodynamic characteristics and speed in intrinsic optical signal imaging. The electrical amplitude decreased through electrocorticographic activity. Intravenous magnesium therapy showed no significant effects on spreading depolarization incidence and characteristics.

Magnesium for Treatment of Reversible Cerebral Vasoconstriction Syndrome: Case Series.

We describe 2 cases of reversible cerebral vasoconstriction syndrome (RCVS) with refractory headache aborted by intravenous magnesium. Case 1 is a 53-year-old woman with subarachnoid hemorrhage due to RCVS presented with refractory headache and persistent vasospasm, despite aggressive treatment with calcium channel blockers (CCBs) and systemic corticosteroids. Subsequently, she experienced dramatic relief of symptoms with intravenous magnesium therapy. She continued oral maintenance therapy and remained symptom free. Case 2 is a 71-year-old female with bilateral temporo-occipital infarcts due to RCVS, presented with refractory headache and persistent vasospasm on transcranial Doppler (TCD), despite aggressive treatment with CCBs. She experienced dramatic relief of symptoms with intravenous magnesium and resolution of vasospasm on TCD. Magnesium may be beneficial for the treatment of refractory headaches in patients with RCVS. Future studies are needed to determine whether it should be considered as a first-line agent.

The Effect of Intravenous Magnesium Therapy on the Duration of Intrathecal Fentanyl Labor Analgesia

The Effect of Intravenous Magnesium Therapy on the Duration of Intrathecal Fentanyl Labor Analgesia

Digoxin Toxicity with Normal Digoxin and Serum Potassium Levels: Beware of Magnesium, the Hidden Malefactor

BackgroundIn recent years, digoxin use has been on the decline, with decreased incidence of digoxin toxicity. Hence, digoxin toxicity, when it occurs, remains an elusive diagnosis to emergency physicians. ObjectiveTo present a case of digoxin toxicity with normal levels of digoxin and serum potassium, but with severe hypomagnesemia. Case ReportA 66-year-old woman presented with junctional tachycardia and ectopic atrial tachycardia. She was known to have congestive cardiac failure on diuretic therapy. Her serum digoxin level was within the normal range (2.4 nmol/L [normal = 1.9–2.6]) along with a normal serum potassium level (3.9 mmol/L [normal = 3.5–5]). However, there was severe hypomagnesemia (0.39 mmol/L [normal = 0.65–1.25]) precipitating digoxin-induced dysrhythmia, which responded well to intravenous magnesium therapy. ConclusionThis case reiterates that digoxin toxicity can occur in patients with normal digoxin and potassium levels, and in such patients, magnesium needs to be checked and treated to prevent potentially life-threatening dysrhythmias.

Significance of serum magnesium levels in reference to acute myocardial infarction and role of intravenous magnesium therapy in prevention of cardiac arrhythmias following myocardial infarction

Introduction: The role of magnesium in treating arrhythmias due to acute myocardial infarction (AMI) has been controversial. Most of the studies have reported a significant reduction in the mortality and frequency of arrhythmias in patients with AMI, who received magnesium therapy, in comparison with control with AMI, who did not receive magnesium treatment. We, therefore, decided that we would evaluate the effect of intravenous magnesium supplement therapy in patients admitted for acute myocardial infarction and if this would be helpful in reducing the morbidity and mortality in patients. Materials and Methods: The study was carried out as a prospective randomized controlled trial of magnesium therapy in acute myocardial infarction. Hundred patients with acute myocardial infarction were randomly divided into two groups of 50 patients each, one for trial and other for placebo therapy. Control group consisted of 20 healthy volunteers of the same age group. All of the 100 patients included in the study had reported within 12 hours of the onset of chest pain. Blood samples for estimation of serum magnesium were taken on admission and on days 2 and 5. Results: The mean age in the Group I and II were 59.52 years ± 15.03 and 59.14 years ± 13.41, respectively. Serum magnesium level on admission was higher in the healthy controls than in the patients of acute myocardial infarction ( P P Conclusions: Intravenous magnesium is a safe and effective method of reducing the frequency of arrhythmias and mortality following the acute myocardial infarction. Magnesium therapy reduces the incidence of arrhythmias and mortality even in the absence of demonstrable magnesium deficiency.

A double‐blinded randomised controlled study of the value of sequential intravenous and oral magnesium therapy in patients with chronic low back pain with a neuropathic component

Persistent mechanical irritation of the nerve root sets up a series of events mediating sensitisation of the dorsal roots and dorsal horns in the spinal cord. Current evidence supports the role of magnesium in blocking central sensitisation through its effect on N-methyl-d-aspartate receptors. We studied the role of sequential intravenous and oral magnesium infusion in patients with chronic low back pain with a neuropathic component. We recruited a cohort of 80 patients with chronic low back pain with a Leeds Assessment of Neuropathic Signs and Symptoms pain scale score ≥ 12, who were receiving a physical therapy programme. All patients were treated with anticonvulsants, antidepressants and simple analgesics; in addition 40 patients received placebo for 6 weeks (control group), while the other 40 patients received an intravenous magnesium infusion for 2 weeks followed by oral magnesium capsules for another 4 weeks (magnesium group). Patients were asked to rate their pain using a numerical rating scale. Lumbar spine range of motion was also determined using a long-arm goniometer. In the magnesium group, the patients' numerical rating scales revealed a significant reduction in pain intensity. The mean (SD) pre-treatment value was 7.5 (2.2) compared with 4.7 (1.8) at 6 months (p = 0.034). The reduction in pain intensity was accompanied by significant improvement in lumbar spine range of motion during the follow-up period. The mean (SD) values of flexion, extension and lateral flexion movements before treatment and at 6-month follow up were 22.2 (8.4) vs 34.7 (11.5) (p = 0.018), 11.8 (3.4) vs 16.9 (3.5) (p = 0.039), 11.4 (3.6) vs 17.2 (4.4) (p = 0.035), respectively. Our findings show that a 2-week intravenous magnesium infusion followed by 4 weeks of oral magnesium supplementation can reduce pain intensity and improve lumbar spine mobility during a 6-month period in patients with refractory chronic low back pain with a neuropathic component.

The effect of intravenous magnesium therapy on the duration of intrathecal fentanyl labor analgesia

BackgroundMagnesium has been reported to augment the analgesic effects of opioids when co-administered into the cerebrospinal fluid. The purpose of this study was to determine the influence of intravenous magnesium therapy administered for preeclampsia on the duration of intrathecal fentanyl analgesia for labor. MethodsThirty-four nulliparous parturients having labor induced for preeclampsia and receiving intravenous magnesium therapy were recruited. Thirty-four nulliparous patients having labor induced for elective or medical reasons were recruited as controls. At request for analgesia, baseline serum magnesium levels were obtained and combined spinal–epidural analgesia was initiated with intrathecal fentanyl 25μg. Before injection of fentanyl, a sample of cerebrospinal fluid was obtained for magnesium assay. An epidural catheter was sited but no additional medications were administered until the second request for analgesia. The primary outcome was duration of intrathecal fentanyl analgesia. ResultsThere was no difference in the median duration of analgesia between the magnesium [79min (95% CI 76 to 82)] and control groups [69min (95% CI 56 to 82)] (difference between medians: 10min (95% CI −4 to 21min; P=0.16). There was neither a relationship between the serum and cerebrospinal fluid magnesium concentrations nor the cerebrospinal magnesium concentration and duration of intrathecal fentanyl analgesia. ConclusionsIntravenous magnesium therapy at doses typically used for seizure prophylaxis in preeclampsia did not influence the duration of intrathecal fentanyl labor analgesia. However, this study may have been underpowered to detect a difference and future study is warranted.

North American Practice Patterns of Intravenous Magnesium Therapy in Severe Acute Asthma in Children

Although intravenous (IV) magnesium (Mg) can decrease hospitalizations in children with severe acute asthma, its use is often limited to resistant disease, and disposition may be determined prior to its use. Since knowledge about practice patterns of IV Mg would enhance knowledge translation and guide future research, we surveyed pediatric emergency physicians with interest in clinical research to determine the frequency, indications, adverse events, and barriers to use of IV Mg in children with severe acute asthma. A cross-sectional online survey of two national pediatric emergency physician associations in Canada and the United States was conducted using a modified Dillman technique. Response rates were 124 of 180 (69%) in Canada and 75 of 108 (69%) in the United States. Although 88% of participants report knowing that Mg is effective, only 14 of 199 (7%) give it to prevent hospitalizations and 142 of 199 (71%) give it to prevent admissions to the intensive care unit (ICU). Thirty-eight percent of respondents use Mg in < 5% of stable children with severe acute asthma, while 79% use it in 50% or more of the ICU candidates with concern about impending respiratory failure. Seventy-nine percent of the participants report that < 5% of their patients given Mg are discharged home from the ED. Twenty-four percent of respondents who administer Mg have encountered associated severe hypotension requiring therapy, and 2% have witnessed-related apnea. Factors affecting Mg use include concern about side effects expressed by 24% of physicians and a belief that IV therapy is not necessary, expressed by 31%. Intravenous Mg appears to be uncommonly used in stable children with severe acute asthma and does not frequently play a role in reducing hospitalizations. Further research to justify its enhanced use and to better establish its true adverse effect profile is indicated.

Magnesium sulphate in the management of patients with aneurysmal subarachnoid haemorrhage: A meta-analysis of prospective controlled trials

Primary objective: Experimental and clinical studies have suggested that magnesium has neuroprotective and vasodilatation properties. A meta-analysis was conducted to assess the effectiveness and safety of intravenous magnesium therapy in patients with aneurysmal subarachnoid haemorrhage (SAH).Research design: Meta-analysis.Methods and procedures: Medline, EMBASE and the Cochrane Library were searched for prospective controlled trials evaluating intravenous magnesium for treating SAH after a ruptured aneurysm without language restrictions. Two researchers performed the literature search and data extraction independently.Main outcomes and results: Six prospective controlled trials involving 699 patients were included in this meta-analysis. Magnesium infusion reduced the risk of poor outcome and delayed cerebral ischemia (DCI): the relative risk was 0.62 (95% confidence interval (CI) 0.46–0.83) and 0.73 (95% CI 0.53–1.00), respectively. Sensitivity analyses were consistent with the meta-analysis. The withdrawal rate for adverse effects was higher in the magnesium-treatment arm compared to the placebo arm, RR 9.98 (95% CI 3.04–32.74).Conclusion: The meta-analysis suggests that intravenous magnesium therapy reduces the risk of DCI and poor outcome after aneurysmal SAH. Serum magnesium should be routinely monitored for both effectiveness and safety considerations.

Prolonged high-dose intravenous magnesium therapy for severe tetanus in the intensive care unit: a case series

IntroductionTetanus rarely occurs in developed countries, but it can result in fatal complications including respiratory failure due to generalized muscle spasms. Magnesium infusion has been used to treat spasticity in tetanus, and its effectiveness is supported by several case reports and a recent randomized controlled trial.Case presentationsThree Caucasian Greek men aged 30, 50 and 77 years old were diagnosed with tetanus and admitted to a general 12-bed intensive care unit in 2006 and 2007 for respiratory failure due to generalized spasticity. Intensive care unit treatment included antibiotics, hydration, enteral nutrition, early tracheostomy and mechanical ventilation. Intravenous magnesium therapy controlled spasticity without the need for additional muscle relaxants. Their medications were continued for up to 26 days, and adjusted as needed to control spasticity. Plasma magnesium levels, which were measured twice a day, remained in the 3 to 4.5 mmol/L range. We did not observe hemodynamic instability, arrhythmias or other complications related to magnesium therapy in these patients. All patients improved, came off mechanical ventilation, and were discharged from the intensive care unit in a stable condition.ConclusionIn comparison with previous reports, our case series contributes the following meaningful additional information: intravenous magnesium therapy was used on patients already requiring mechanical ventilation and remained effective for up to 26 days (significantly longer than in previous reports) without significant toxicity in two patients. The overall outcome was good in all our patients. However, the optimal dose, optimal duration and maximum safe duration of intravenous magnesium therapy are unknown. Therefore, until more data on the safety and efficacy of magnesium therapy are available, its use should be limited to carefully selected tetanus cases.

Magnesium and headache after aneurysmal subarachnoid haemorrhage

BackgroundIn patients with aneurysmal subarachnoid haemorrhage (SAH), headache typically is severe and often requires treatment with opioids. Magnesium has analgesic effects in several conditions, but whether it reduces headache after...

Chemotherapy-induced peripheral neuropathy: Prevention and treatment strategies

Chemotherapy-induced peripheral neuropathy (CIPN) is a major dose limiting side effect of many commonly used chemotherapeutic agents, including platinum drugs, taxanes, epothilones and vinca alkaloids, and also newer agents such as bortezomib and lenolidamide. Symptom control studies have been conducted looking at ways to prevent or alleviate established CIPN. This manuscript provides a review of studies directed at both of these areas. New evidence strongly suggests that intravenous calcium and magnesium therapy can attenuate the development of oxaliplatin-induced CIPN, without reducing treatment response. Accumulating data suggest that vitamin E may also attenuate the development of CIPN, but more data regarding its efficacy and safety should be obtained prior to its general use in patients. Other agents that look promising in preliminary studies, but need substantiation, include glutamine, glutathione, N-acetylcysteine, oxcarbazepine, and xaliproden. Effective treatment of established CIPN, however, has yet to be found. Lastly, paclitaxel causes a unique acute pain syndrome which has been hypothesised to be caused by neurologic injury. No drugs, to date, have been proven to prevent this toxicity.

Effect of Magnesium on Red Blood Cell Deformability in Pregnancy

Objective. Red blood cell (RBC) deformability is an important factor in determining movement of red blood cells through the microcirculation. In preeclampsia and some cases of intrauterine growth restriction (IUGR), RBC deformability and microcirculation are reduced. Magnesium is administered to reduce the risk of seizures. The aim of this study was first to detect the effect of intravenous magnesium application (2 g/h) on the deformability of RBCs in pregnancies with normal RBC deformability, receiving magnesium as tocolytic agent. The second aim was to examine the effect of calcium-antagonists (magnesium, nifedipin) on the deformability of RBC of preeclamptic patients in vitro. Methods. Part 1: magnesium (2 g/h), fenoterol (270 µg/h) + verapamil (0.2 mg/h) or placebo (NaCl 0.9%) was administered intravenously to pregnant women with premature contractions to test the tocolytic effect. RBC-deformability was measured by laser diffractoscopy in all three groups. Blood samples were taken before, after 1 h and after 24 h of administration. Magnesium-plasma-levels were measured. Part 2: Blood samples from patients with preeclampsia were incubated in vitro with magnesium (2 mmol), nifedipine (0.25 mg/ml), or placebo (NaCl 0.9%). RBC deformability was measured before and 15 min, 1h, 2h, 6h, and 10h after start of the incubation. Results. Part 1: The initial RBC-deformability was the same in all groups (E=0.232 ± 0.017 in NaCl, 0.232 ± 0.023 in fenoterol + verapamil, 0.232 ± 0.019 in magnesium). After 1 h of administration, RBC-deformability was significantly greater with magnesium (0.254 ± 0.020) and Fenoterol + Verapamil (0.238 ± 0.02) compared to placebo (0.231 ± 0.015). After 24 h the effect on RBC deformability in the fenoterol + verapamil-group was gone (0.234 ± 0.021 compared to 0.234 ± 0.016 in placebo), while in the IV-magnesium-group RBC-deformability remained increased (E=0.241 ± 0.019). Statistical analysis of the influence of magnesium-plasma-levels showed the maximum effect at concentrations of 1.95–2.15mmol/l. Part 2: RBC-deformability in preeclampsia was reduced as predicted by previous studies (0.120 + 0.0086 versus 0.232 in normal pregnancy). In vitro incubation with magnesium enhanced RBC-deformability in preeclampsia. Even after 15 min, a statistically significant effect was seen (0.127 ± 0.0091 versus 0.121 ± 0.0091 in placebo). Maximum effect was reached after 6 h of incubation (0.159 ± 0.0093 versus 0.133 ± 0.0091). Incubation with Nifedipine also enhanced RBC deformability [0.127 ± 0.0091 after 15 min, 0.149 ± 0.010 after 6 h (maximum effect)], but the effect was less pronounced than with magnesium. Conclusion. Intravenous magnesium therapy over a 24-hour period increases RBC-deformability even in pregnancies with normal RBC-deformability. In vitro measurements show an increase of RBC-deformability in preeclampsia in response to magnesium, which could offer additional therapeutic benefit for the treatment of reduced blood flow seen in most cases of preeclampsia.