Letter to editor: Serum concentration-guided intravenous magnesium sulfate administration for neuroprotection in patients with aneurysmal subarachnoid hemorrhage: A retrospective evaluation of a 12-year single-center experience

This critique examines a 12-year retrospective study on serum magnesium concentration-guided administration of magnesium sulfate in 548 patients with aneurysmal subarachnoid hemorrhage (aSAH). The study reported that maintaining serum magnesium levels between 2 and 2.5 mmol/L reduced rates of delayed cerebral infarction and improved clinical outcomes. However, limitations due to its retrospective nature, single-center design, and unequal treatment group sizes may affect generalizability. Future multicentric randomized controlled trials are recommended to validate these findings and refine magnesium dosing strategies for aSAH treatment.

Magnesium sulfate in preeclampsia: Broad indications, not only in neurological symptoms

The role of magnesium sulfate for treatment of eclampsia is well established. The medication proved to be superior to other anticonvulsants to reduce the incidence of recurrent convulsions among women with eclampsia. Additionally, magnesium sulfate has been indicated for women with preeclampsia with different severe features. However, despite these recommendations, many clinicians are still not confident with the use of magnesium sulfate, even in settings with high incidence of preeclampsia and unacceptable rates of maternal mortality. This review brings basic science and clinical information to endorse recommendations to encourage clinicians to use magnesium sulfate for patients with all severe features of preeclampsia, not only for women with neurological symptoms. Additionally, other benefits of magnesium sulfate in anesthesia and fetal neuroprotection are also presented. Finally, a comprehensive algorithm presents recommendations to manage patients with preeclampsia with severe features between 34 and 36+6 weeks.

Management of organophosphorus poisoning and the role of magnesium sulfate: A scoping review of literature

Organophosphorus agents are easily absorbed via respiratory, gastrointestinal, and dermal routes, and inhibit the acetylcholine transferase enzyme (AChE), which is responsible for the majority of toxicity caused by organophosphates in the body. A comprehensive search was conducted across three prominent databases, namely Google Scholar, PubMed, and Science Direct, to identify relevant articles published. The search focused on the keywords "MgSO4" or "magnesium sulfate" in conjunction with "organophosphate" or "organophosphate poisoning." Inhibition of AChE results in the accumulation of acetylcholine (ACh) in synapses and stimulation of cholinergic receptors. Considering that several studies have shown the use of magnesium sulfate (MgSO4) in inhibiting the release of ACh in the central and peripheral sympathetic and parasympathetic synapses, this study was conducted to review the role of MgSO4 in the treatment of OP. The intravenous administration of MgSO4 exhibits favorable tolerability and clinical efficacy in alleviating cardiac toxicity associated with OP exposure.

Gender Differences With Ibutilide Effectiveness and Safety in Cardioversion of Atrial Fibrillation

INTRODUCTION

Few studies have examined the use of ibutilide in noncardiac surgical populations. Our study considered the effectiveness and safety of ibutilide in cardioversion of atrial fibrillation (AF) in medical and surgical intensive care patients.

METHODS

A retrospective chart review was performed for patients with a confirmed diagnosis of AF who were hemodynamically stable and received ibutilide after the initial diagnosis. Patients were administered 1 mg of ibutilide fumarate intravenous for 10 min with a second dose administered if AF persisted after 30 min. Patients were pretreated with intravenous magnesium sulfate if their blood magnesium level was <2 mg/dL.

RESULTS

Fifty seven total female patients and 99 male patients received ibutilide. Females had an 88% conversion rate to normal sinus rhythm (NSR) compared to 68% in males (P = 0.008). A 70% successful return to NSR was observed in patients from all groups pretreated with magnesium sulfate (P = 0.045). One year after discharge, 74% of the patients stayed in the NSR.

CONCLUSIONS

Within our population, pretreatment with magnesium sulfate followed by ibutilide was associated with increased conversion to NSR. Additionally, we noted that females had a higher conversion rate to NSR compared to males, regardless of whether they were pretreated with magnesium sulfate.

Early Intravenous Magnesium Sulfate and Its Impact on Cerebral Vasospasm as well as Delayed Cerebral Ischemia in Aneurysmal Subarachnoid Hemorrhage: A Retrospective Matched Case-Control Analysis

BACKGROUND

Magnesium sulfate (MgSO4) is a potential neuroprotective agent for patients with aneurysmal subarachnoid hemorrhage (SAH). We analyzed the effect of early application of intraoperative intravenous MgSO4 and compared cerebral vasospasm (CV), delayed cerebral ischemia (DCI), and neurological outcome in 2 patient cohorts.

METHODS

A retrospective matched-pair analysis from patients at a single center in Germany was performed without (group A) and with (group B) MgSO4 application <24 hours after diagnosis. Pairs were matched according to the known risk factors for DCI and CV (age, Fisher grade, smoking, severity of SAH). Incidence of CV and DCI and neurological outcome using the modified Rankin Scale score 3 and 12 months after SAH were recorded.

RESULTS

The inclusion criteria were met by 196 patients. After risk stratification, 48 patients were included in the final analysis (age 54.2 ± 8.1 years; 30 women and 18 men) and were assigned to group A (n = 24) or group B (n = 24). CV occurred less frequently in group B (33%) than in group A (46%). Likewise, DCI was present in 13% in group B compared with 42% in group A. After 12 months, 22 patients in group B had a favorable functional outcome (modified Rankin Scale score 0-3) compared with 15 patients in group A.

CONCLUSIONS

In this study, the incidence of CV and DCI was lower in patients receiving intravenous MgSO4 within 24 hours after aneurysmal SAH onset. Favorable functional outcome was more likely in the MgSO4 group after 12 months of follow-up.

Maternal and neonatal outcomes following magnesium sulfate in the setting of chorioamnionitis: a meta-analysis

PURPOSE

Magnesium sulfate (MgSO4) has been widely used in obstetrics as a mean to help decrease maternal and neonatal morbidity in various antenatal pathology. As a factor, it seems to regulate immunity and can, thus, predispose to infectious morbidity. To date, it remains unknown if its administration can increase the risk of chorioamnionitis. In the present meta-analysis, we sought to accumulate the available evidence.

METHODS

We systematically searched Medline, Scopus, Clinicaltrials.gov, EMBASE, Cochrane Central Register of Controlled Trials CENTRAL, and Google Scholar databases in our primary search along with the reference lists of electronically retrieved full-text papers.

RESULTS

Eight studies were included that investigated the incidence of chorioamnionitis among parturient that received MgSO4 and control patients. Magnesium sulfate was administered in 3229 women and 3330 women served as controls as they did not receive MgSO4. The meta-analysis of data revealed that there was no association between the administration of magnesium sulfate and the incidence of chorioamnionitis (OR 0.98, 95% CI 0.73, 1.32). Rucker's analysis revealed that small studies did not significantly influence the statistical significance of this finding (OR 1.12, 95% CI 0.82, 1.53). Trial sequential analysis revealed that the required number to safely interpret the primary outcome was not reached. Two studies evaluated the impact of MgSO4 in neonates delivered in the setting of chorioamnionitis. Neither of these indicated the presence of a beneficial effect in neonatal morbidity, including the risk of cerebral palsy, intraventricular hemorrhage, necrotizing enterocolitis, bronchopulmonary dysplasia, sepsis, stillbirth, or neonatal death.

CONCLUSION

Current evidence indicates that magnesium sulfate is not associated with an increased risk of maternal chorioamnionitis. However, it should be noted that its effect on neonatal outcomes of offspring born in the setting of chorioamnionitis might be subtle if any, although the available evidence is very limited.

Uterotonics, magnesium sulphate and antibiotics during childbirth and peripartum: Important obstetric drugs for the anaesthesiologist

The main causes of maternal mortality are comorbidities, hypertensive pregnancy syndrome, obstetric haemorrhage, and maternal sepsis. For this reason, uterotonics, magnesium sulphate, and antibiotics are essential tools in the management of obstetric patients during labour and in the peripartum period. These drugs are widely used by anaesthesiologists in all departments, and play a crucial role in treatment and patient safety. For the purpose of this narrative review, we performed a detailed search of medical databases and selected studies describing the use of these drugs in patients during pregnancy, delivery and the pospartum period. Uterotonics, above all oxytocin, play an important role in the prevention and treatment of pospartum haemorrhage, and various studies have shown that in obstetric procedures, such as scheduled and emergency caesarean section, they are effective at lower doses than those hitherto accepted. We also discuss the use of carbetocin as an effective alternative that has a therapeutic advantage in certain clinical circumstances. Magnesium sulphate is the gold standard in the prevention and treatment of eclampsia, and also plays a neuroprotective role in preterm infants. We describe the precautions to be taken during magnesium administration. Finally, we discuss the importance of understanding microbiology and the pharmacology of antibiotics in the management of obstetric infection and endometritis, and draw attention to the latest trends in antibiotic regimens in labour and caesarean section.

Use of non-invasive cardiac monitoring to guide discontinuation of postpartum magnesium sulfate in individuals with preeclampsia with severe features

OBJECTIVES

To determine the utility of using total peripheral systemic vascular resistance assessed using non-invasive cardiac monitor for individualizing the duration of postpartum magnesium sulfate in individuals with preeclampsia with severe features.

STUDY DESIGN

Single center pilot randomized controlled trial in which singleton pregnant individuals with preeclampsia with severe features were randomized to 24 h of postpartum magnesium sulfate per standard of care (control group) or individualized duration of postpartum magnesium sulfate based on reduction in post-delivery systemic vascular resistance (intervention group). Systemic vascular resistance was assessed with non-invasive cardiac monitoring using the Cheetah® system. A 30 % reduction (maintained for 1 h) from baseline post-delivery systemic vascular resistance was used as a cutoff for discontinuation of postpartum magnesium sulfate. Our primary outcome was duration of postpartum magnesium sulfate use in hours. Secondary outcomes included a composite of maternal morbidities associated with preeclampsia.

RESULTS

Of 53 individuals enrolled, we excluded 6 from this analysis due to insufficient data to assess primary outcome. Baseline characteristics of the control (n = 26) and intervention (n = 21) groups were similar. Six (28.6 %) individuals in intervention group met the systemic vascular resistance criteria and had their postpartum magnesium sulfate discontinued before 24 h. The duration of postpartum magnesium sulfate infusion was shorter in the intervention group (21.6 ± 4.7 h; range: 7-24 h) compared with control group (24 h, p = 0.02). There was no difference in secondary outcomes between the two groups. There was no difference in adverse outcomes in individuals that had magnesium discontinued earlier than 24 h.

CONCLUSION

Non-invasive monitoring of systemic vascular resistance can be a valuable tool to individualize the duration of postpartum magnesium sulfate for preeclampsia with severe features. These findings should be conformed in a larger trial.

Buprenorphine induced opioid withdrawal syndrome relieved by adjunctive Magnesium: A clinical trial

INTRODUCTION

Precipitated opioid withdrawal syndrome (OWS) is a severe and intolerable situation that may occur by a pharmaceutical agent. Reactivation of inhibited N-methyl-d-aspartate (NMDA) receptor in person with prolonged opioid use can led to severe OWS. We conducted a double-blind, randomized clinical trial to assess the effect of magnesium sulfate (MGSO4) as an NMDA receptor antagonist on OWS.

MATERIALS AND METHODS

The study randomly divided forty patients with precipitated OWS due to partial agonist (buprenorphine) use referred to the emergency unit of Toxicology Department of Mashhad University of Medical Sciences, Iran; into two groups. The control group received conventional therapies, including clonidine 0.1 mg tablet each hour, intravenous infusion of 10 mg diazepam every 30 min, and IV paracetamol (Acetaminophen) 1 g, while the intervention group received 3 g of MGSO4 in 20 min and then 10 mg/kg/h up to 2 h, in addition to the conventional treatment. The clinical opiate withdrawal scale (COWS) evaluated OWS at the start of the treatment, 30 min, and 2 h later.

RESULTS

Both groups had similar demographic, opiate types, and COWS severity at the start of the intervention. COWS was lower in the intervention than the control group at 30 min (11.20 ± 2.86 and 14.65 ± 2.36, respectively, P = 0.002) and at 2 h (3.2 ± 1.61 and 11.25 ± 3.27, respectively, P < 0.001) after treatment. The intervention group received lesser doses of clonidine (0.12 ± 0.51 and 0.17 ± 0.45 mg, P = 0.003) and Diazepam (13.50 ± 5.87, 24.0 ± 6.80 mg, P = 0.001) than the control group. Serum magnesium levels raised from 1.71 ± 0.13 mmol/L to 2.73 ± 0.13 mmol/L in the intervention group.

CONCLUSION

Magnesium can significantly reduce the severity of OWS. Additional studies are required to confirm these results.

Effect of magnesium sulfate perioperative infusion on postoperative catheter-related bladder discomfort in male patients undergoing laparoscopic radical resection of gastrointestinal cancer: a prospective, randomized and controlled study

BACKGROUND

Laparoscopic radical resection of gastrointestinal cancer is associated with a high incidence of postoperative catheter-related bladder discomfort (CRBD). Studies on the benefits of magnesium sulfate intravenous infusion during the perioperative period post-laparoscopic surgery are yet lacking.

METHODS

A total of 88 gastrointestinal cancer male patients scheduled for laparoscopic radical resection were randomly divided into two groups: normal saline (control) and magnesium. In the magnesium group, a 40 mg/kg loading dose of intravenous magnesium sulfate was administered for 10 min just after the induction of anesthesia, followed by continuous intravenous infusion of 15 mg/kg/h magnesium sulfate until the end of the surgery; the control group was administered the same dose of normal saline. Subsequently, 2 μg/kg sufentanil was continuously infused intravenously by a postoperative patient-controlled intravenous analgesia (PCIA) device. The primary outcome was the incidence of CRBD at 0 h after the surgery. The secondary outcomes included incidence of CRBD at 1, 2, and 6 h postsurgery, the severity of CRBD at 0, 1, 2, and 6 h postsurgery. Remifentanil requirement during surgery, sufentanil requirement within 24 h postsurgery, the postoperative numerical rating scale (NRS) score at 48 h after the surgery, magnesium-related side effects and rescue medication (morphine) requirement were also assessed.

RESULTS

The incidence of CRBD at 0, 1, 2, and 6 h postoperatively was lower in the magnesium group than the control group (0 h: P = 0.01; 1 h: P = 0.003; 2 h: P = 0.001; 6 h: P = 0.006). The incidence of moderate to severe CRBD was higher in the control group at postoperative 0 and 1 h (0 h: P = 0.002; 1 h: P = 0.028), remifentanil requirement during surgery were significantly lower in the magnesium group than the control group. Sufentanil requirements during the 24 h postoperative period were significantly lower in the magnesium group than the control group. The NRS score was reduced in the magnesium group compared to the control group in the early postoperative period. Magnesium-related side effects and rescue medication (morphine) did not differ significantly between the two groups.

CONCLUSIONS

Intravenous magnesium sulfate administration reduces the incidence and severity of CRBD and remifentanil requirement in male patients undergoing radical resection of gastrointestinal cancer. Also, no significant side effects were observed.

TRIAL REGISTRATION

Chictr.org.cn ChiCTR2100053073. The study was registered on 10/11/2021.

Effect of magnesium sulfate on oxygenation and lung mechanics in morbidly obese patients undergoing bariatric surgery: a prospective double-blind randomized clinical trial

BACKGROUND

Respiratory mechanics are often significantly altered in morbidly obese patients and magnesium sulfate (MgSO4) is a promising agent for managing several respiratory disorders. This study aimed to examine the effects of MgSO4 infusions on arterial oxygenation and lung mechanics in patients with morbid obesity undergoing laparoscopic bariatric surgery.

METHODS

Forty patients with morbid obesity aged 21-60 years scheduled for laparoscopic bariatric surgery under general anesthesia were randomly allocated to either the control (normal saline infusion) or MgSO4 group (30 mg/kg lean body weight [LBW] of 10% MgSO4 in 100 ml normal saline intravenously over 30 min as a loading dose, followed by 10 mg/kg LBW/h for 90 min). The primary outcome was intraoperative arterial oxygenation (ΔPaO2/FiO2). Secondary outcomes included intraoperative static and dynamic compliance, dead space, and hemodynamic parameters.

RESULTS

At 90 min intraoperatively, the Δ PaO2/FiO2 ratio and the Δ dynamic lung compliance were statistically significantly higher in the MgSO4 group (mean ± SE: 16.1 ± 1.0, 95% CI [14.1, 18.1] and 8.4 ± 0.5 ml/cmH2O, 95% CI [7.4, 9.4]), respectively), and the Δ dead space (%) was statistically significantly lower in the MgSO4 group (mean ± SE: -8.0 ± 0.3%, 95% CI [-8.6, -7.4]) (P < 0.001). No significant differences in static compliance were observed.

CONCLUSIONS

Although MgSO4 significantly preserved arterial oxygenation and maintained dynamic lung compliance and dead space in patients with morbid obesity, the clinical relevance is minimal. This study failed to adequately reflect the clinical importance of these results.

Management of preterm labor: Clinical practice guideline and recommendation by the WAPM-World Association of Perinatal Medicine and the PMF-Perinatal Medicine Foundation

This practice guideline follows the mission of the World Association of Perinatal Medicine in collaboration with the Perinatal Medicine Foundation, bringing together groups and individuals throughout the world, with the goal of improving the management of preterm labor. In fact, this document provides further guidance for healthcare practitioners on the appropriate use of examinations with the aim to improve the accuracy in diagnosing preterm labor and allow timely and appropriate administration of tocolytics, antenatal corticosteroids and magnesium sulphate and avoid unnecessary or excessive interventions. Therefore, it is not intended to establish a legal standard of care. This document is based on consensus among perinatal experts throughout the world in the light of scientific literature and serves as a guideline for use in clinical practice.

The effect of magnesium sulfate on gene expression and serum level of inflammatory cytokines in coronary artery disease patients

PURPOSE

To evaluate the effect of oral magnesium sulfate (MgSO4) on the gene expression and serum levels of inflammatory cytokines including TNF-α, IL-18, IL-1β, IL-6, and IFN-γ in patients with moderate coronary artery disease (CAD).

METHODS

60 CAD patients were selected based on angiography findings and were randomly divided into two groups that received 300 mg/day MgSO4 (n = 30) or placebo (n = 30) for 3 months. Gene expression and serum levels of inflammatory cytokines were assessed.

RESULTS

After 3 months of intervention, gene expression and serum levels of IL-18 and TNF-α in the MgSO4 group were significantly less than the placebo group (P < 0.05). However, no significant difference in gene expression and serum levels of IL-1β, IL-6, and IFN-γ was observed between the two groups (P > 0.05). In addition, within group analysis demonstrate that Mg-treatment significantly decrease serum level of TNF-α and IL-18 as compared to pretreatment.

CONCLUSION

The results of our study demonstrate that 3-month magnesium sulfate administration (300 mg/day) to CAD patients could significantly decrease serum concentration and gene expression levels of IL-18 and TNF-α. Our findings support the potential beneficial effect of magnesium supplementation on alleviating CAD complications through modulating inflammatory cytokines.

Serum concentration-guided intravenous magnesium sulfate administration for neuroprotection in patients with aneurysmal subarachnoid hemorrhage: a retrospective evaluation of a 12-year single-center experience

Delayed cerebral infarction (DCI) is a major cause of morbidity and mortality in patients with aneurysmal subarachnoid hemorrhage (aSAH). The benefits of magnesium sulfate as an alternative treatment are controversial, and most previous studies examined its benefits only as adjunctive treatment to traditional nimodipine. We retrospectively analyzed aSAH patients records with magnesium sulfate between 2010 and 2021. We aimed for a serum magnesium concentration of 2-2.5 mmol/l between post-hemorrhage days 3 and 12. The patients were separated in three groups based on average serum magnesium concentration (magnesium >2 mmol/l, reduced magnesium 1.1-1.9 mmol/l, and no magnesium). Additionally, we assessed delayed cerebral infarction (DCI) and clinical outcome at follow-up, using the modified Rankin Scale (mRS), categorized in favorable (0-3) and unfavorable outcome (4-5). In this analysis, 548 patients were included. Hereof, radiological evidence of DCI could be found in 23.0% (n = 126) of patients. DCI rates were lower if patients' average serum magnesium was higher than 2 mmol/l (magnesium 18.8%, n = 85; reduced magnesium 38.3%, n = 23; no magnesium 51.4%, n = 18; p < 0.001). Also, at the last follow-up, patients in the group with a higher serum magnesium concentration had better outcome (favorable outcome: magnesium 64.7%, n = 293; reduced magnesium 50.0%, n = 30; no magnesium 34.3%, n = 12; p < 0.001). This 12-year study reveals the value of serum concentration-guided magnesium administration in aSAH patients. Our findings demonstrate the safety and efficacy when titrated to a serum concentration of 2-2.5 mmol/l. We observed higher rates of delayed cerebral infarction and unfavorable outcomes in patients with serum concentrations below 2 mmol/l.

Effects of intraoperative Magnesium sulfate infusion on emergency agitation during general anesthesia in patients undergoing radical mastectomy: a randomized controlled study

BACKGROUND

Emergency agitation is a common postoperative complication in patients under general anesthesia, which can lead to unpredictable damages such as shedding of drainage tube and bleeding from the wound. The purpose of the study is to investigate whether intraoperative infusion of Magnesium Sulfate reduces the incidence of emergency agitation (EA) in patients undergoing radical mastectomy, and to evaluate its safety and efficacy.

METHODS

A total of 70 patients were randomly assigned to two groups: the Magnesium group (M group) and the control group (C group). After a routine intravenous anesthetic induction, patients in the M group received a 30 mg/kg bolus of intravenous magnesium during the first hour and then a continuous infusion of 10 mg/kg ×h until the end of the surgery, patients in the C group received 0.9% saline at the same volume and rate. The sedation-agitation scale (SAS) and the visual analogue scale were used to assess agitation and pain, respectively.

RESULTS

Compared to the C group, the M group reduced the incidence of EA significantly (odds ratio 0.26, 95% confidence interval 0.09-0.71, P = 0.009). The postoperative pain score of the magnesium sulfate group(0(0,1)) was lower than that of the control group(2(0,3)) at T0 (P = 0.011). Additionally, the M group required a lower dosage of remifentanil during surgery compared to the C group(300.4 ± 84 versus 559.3 ± 184 µg, respectively, P<0.001).

CONCLUSIONS

the intraoperative infusion of magnesium sulfate is a safe and effective method for reducing the incidence of emergency agitation in patients undergoing radical mastectomy.

TRAIL REGISTRATION

The study was registered in Chictr.org with the identifier: ChiCTR2300070595 on 18/04/2023.

Efficacy of magnesium sulfate combined with nifedipine for pregnancy-induced hypertension syndrome and its relation to glucose and lipid metabolism

OBJECTIVE

To determine the efficacy of magnesium sulfate combined with nifedipine for pregnancy-induced hypertension syndrome (PIHS) and its influence on glucose and lipid metabolism.

METHODS

The clinical data of 124 cases of PIHS treated in Jiangxi Jiujiang Maternal and Child Care Centers from March 2020 to June 2022 were collected and retrospectively analyzed. Among them, 58 patients who received magnesium sulfate alone were enrolled as a control group, and the other 66 given magnesium sulfate combined with nifedipine were enrolled as a study group. The two groups were compared for treatment efficacy, blood pressure, fasting blood glucose (FBG) and blood lipid indexes (triglycerides (TG), high-density lipoprotein-cholesterol (HDL-C), total cholesterol (TC), and low-density lipoprotein - cholesterol (LDL-C)). Multivariate logistic regression analysis was performed to analyze the factors affecting outcome.

RESULTS

The study group showed a significantly higher total effective rate than the control group (P=0.008). After treatment, the study group showed significantly lower systolic blood pressure (SBP) and diastolic blood pressure (DBP) levels than the control group (P<0.001). After treatment, the study group also showed lower levels of FBG, TC, TG, and LDL-C and a higher HDL-C level than the control group (P<0.001). Additionally, the incidences of cesarean section and postpartum hemorrhage were lower in the study group than those of the control group (both P<0.05). The two groups were not significantly different in premature delivery or low neonatal birth weight (both P>0.05), and the incidence of adverse reactions of the two groups was also not greatly different (P>0.05). According to multivariate logistic regression analysis, higher BMI (OR: 3.087, 95% CI: 1.295~7.358) and higher SBP (OR: 1.220, 95% CI: 1.001~1.487) at admission were independent risk factors for poor efficacy, while combined therapeutic regimen (OR: 0.018, 95% CI: 0.001~0.228) was an independent protective factor.

CONCLUSION

Magnesium sulfate combined with nifedipine can deliver a powerful clinical efficacy for patients with PIHS by lowering blood pressure and the incidence of adverse pregnancy outcomes and by improving glucose and lipid metabolism.

Intra-Operative Adjunctive Magnesium Sulfate in Pain Management of Total Knee Arthroplasty; a Systematic Review and Meta-analysis

Introduction

There has been growing interest in the potential role of adjunctive magnesium sulfate in improving pain management. This systematic review and meta-analysis aimed to assess the effect of intra-operative adjunctive magnesium sulfate on pain management and opioid consumption in total knee arthroplasty (TKA).

Methods

A comprehensive search was conducted in Medline, Embase, Scopus, Web of Science, and Cochrane Library databases, covering studies up to April 2023. The extracted data included pain management outcomes, opioid consumption, and adverse effects from the selected studies. Standardized mean differences (SMDs) were calculated for continuous outcomes, while risk ratios (RRs) were calculated for dichotomous outcomes. Meta-analysis was conducted employing random-effects models in STATA 17.

Results

In this meta-analysis of 8 randomized controlled trials involving 536 patients, adjunctive magnesium sulfate in TKA was found to significantly reduce opioid consumption during the first 24 hours after operation (SMD: -1.88, 95% confidence interval (CI): [-3.66 to -0.10]; p = 0.038). It also resulted in lower pain scores at rest 24 hours after surgery (SMD: -1.53, 95% CI: [-2.70 to -0.37]; p = 0.010). There were no significant differences in time to first rescue analgesic and adverse effects between the groups. The included studies were assessed to have low to high levels of risk of bias.

Conclusion

This study presents evidence at low to moderate levels supporting the use of intra-operative adjunctive magnesium sulfate in TKA for improved pain management and reduced opioid consumption. However, further research is needed to address the heterogeneity and to explore optimal dosing regimens and routes of administration to maximize the benefits of magnesium sulfate in TKA.

Recurarization with magnesium sulfate administered after two minutes sugammadex reversal: A randomized, double-blind, controlled trial

STUDY OBJECTIVE

The current study tested the hypothesis that magnesium sulfate after reversal with sugammadex causes recurarization.

DESIGN

A single-center, prospective, randomized, double-blind, controlled trial.

SETTING

Terciary care hospital in Rio de Janeiro, Brazil.

PATIENTS

Included 60 patients undergoing for elective otolaryngological surgery.

INTERVENTIONS

All patients received total intravenous anesthesia and a single dose of rocuronium (0.6 mg/kg). In 30 patients, the neuromuscular blockade was reversed with sugammadex (4 mg/kg) at the reappearance of one or two posttetanic counts (deep-blockade series). In 30 other patients, sugammadex (2 mg/kg) was administered at the reappearance of the second twitch of the train-of-four (moderate-blockade series). After the normalized train-of-four ratio recovered to ≥0.9, the patients in each series were randomized to receive intravenous magnesium sulfate (60 mg/kg) or placebo for 10 min. Neuromuscular function was measured by acceleromyography.

MEASUREMENTS

The primary outcome was the number of patients who exhibited recurarization (normalized train-of-four ratio < 0.9). The secondary outcome was rescue with an additional dose of sugammadex after 60 min.

MAIN RESULTS

In the deep-blockade series, a normalized train-of-four ratio < 0.9 occurred in 9/14 (64%) patients receiving magnesium sulfate and 1/14 (7%) receiving placebo, RR 9.0 (95% CI: 62-1.30), and (p = 0.002), with four rescues with sugammadex. In the moderate-blockade series, neuromuscular blockade recurred in 11/15 (73%) patients receiving magnesium sulfate and in 0/14 (0%) receiving placebo (p < 0.001), with two rescues. The absolute differences in recurarization were 57% and 73% in the deep-blockade and moderate-blockade, respectively.

CONCLUSIONS

Single-dose magnesium sulfate led to a normalized train-of-four ratio < 0.9, 2 min after recovery from rocuronium-induced deep and moderate neuromuscular blockade using sugammadex. Additional sugammadex reversed prolonged recurarization.

Effects of magnesium sulfate on periarticular infiltration analgesia in total knee arthroplasty: a prospective, double-blind, randomized controlled trial

BACKGROUND

To investigate whether adding magnesium sulfate to a periarticular infiltration analgesia (PIA) cocktail could improve pain control and functional outcomes in patients undergoing total knee arthroplasty (TKA).

METHODS

Ninety patients were randomly assigned to the magnesium sulfate and control groups, with 45 patients in each group. In the magnesium sulfate group, patients were given a periarticular infusion of a cocktail of analgesics consisting of epinephrine, ropivacaine, magnesium sulfate, and dexamethasone. The control group received no magnesium sulfate. The primary outcomes consisted of visual analogue scale (VAS) pain scores, postoperative morphine hydrochloride consumption for rescue analgesia, and time to first rescue analgesia. Secondary outcomes were postoperative inflammatory biomarkers (IL-6 and CRP), postoperative length of stay, and knee functional recovery (assessed by knee range of motion, quadriceps strength, daily mobilization distance, and time to first straight-leg raising). Tertiary outcomes included the postoperative swelling ratio and complication rates.

RESULTS

Within 24 h of surgery, patients in the magnesium sulfate group had markedly lower VAS pain scores during motion and at rest. After the addition of magnesium sulfate, the analgesic effect was dramatically prolonged, leading to a reduction in morphine dosage within 24 h and the total morphine dosage postoperatively. Postoperative inflammatory biomarker levels were significantly reduced in the magnesium sulfate group compared with the control. There were no considerable differences between the groups in terms of the postoperative length of stay and knee functional recovery. Both groups had similar postoperative swelling ratios and incidences of complications.

CONCLUSIONS

The addition of magnesium sulfate to the analgesic cocktail for PIA can prolong postoperative analgesia, decrease the consumption of opioids, and effectively alleviate early postoperative pain after TKA.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2200056549. Registered on 7 February 2022, https://www.chictr.org.cn/showproj.aspx?proj=151489 .

The role of a combination of N-acetylcysteine and magnesium sulfate as adjuvants to standard therapy in acute organophosphate poisoning: A randomized controlled trial

Background

Mortality in acute organophosphate (OP) poisoning remains high despite current standard therapy with atropine and oximes. Due to dose-limiting side effects of atropine, novel therapies are targeting other putative mechanisms of injury, including oxidative damage, to reduce atropine dosage.

Objectives

N-acetylcysteine (NAC) and magnesium sulfate (MgSO₄) have different mechanisms of actions and should act synergistically in OP poisoning. In this study, we wanted to evaluate whether this novel combination, used as an adjuvant to standard care, could improve clinical outcomes.

Methods

The study was conducted in the Emergency Department and ICU of AIIMS Bhubaneswar (a tertiary care center and government teaching institute) between July 2019 and July 2021. Eighty-eight adult patients with history and clinical features of acute OP poisoning were randomly allocated (1:1) into two groups. The Study group received 600 mg NAC via nasogastric tube thrice daily for 3 days plus a single dose of 4 g Inj. MgSO₄ IV on first day and the Control group received suitably matched placebo (double-blinding) - in addition to standard care in both the groups. The primary outcome measure was to compare the total dose of Inj. Atropine required (cumulative over the entire treatment duration) between the control group and the study group receiving NAC and MgSO₄. The secondary outcome measures were lengths of ICU and hospital stays, need and duration of mechanical ventilation, the differences in BuChE activity, oxidative stress biomarkers - MDA and GSH levels, the incidences of adverse effects including delayed sequalae like intermediate syndrome and OPIDN, and comparison of mortality between the two groups.

Results

Data from 43 patients in Control and 42 patients in Study group was finally analyzed. The baseline parameters were comparable. Total atropine requirements were lower in the Study group [175.33 ± 81.25 mg (150.01-200.65)] compared to the Control [210.63 ± 102.29 mg (179.15-242.11)] [Mean ± SD (95% CI)], but was not statistically significant. No significant differences in any of the other clinical or biochemical parameters were noted.

Conclusion

The N-acetylcysteine and MgSO₄ combination as adjuvants failed to significantly reduce atropine requirements, ICU/hospital stay, mechanical ventilatory requirements, mortality and did not offer protection against oxidative damage.

Effect of magnesium sulfate with ketamine infusions on intraoperative and postoperative analgesia in cancer breast surgeries: a randomized double-blind trial

BACKGROUND

Opioids are the cornerstone in managing postoperative pain; however, they have many side effects. Ketamine and Magnesium (Mg) are NMDA receptor antagonists used as adjuvant analgesics to decrease postoperative opioid consumption.

OBJECTIVE

We assumed that adding Mg to ketamine infusion can improve the intraoperative and postoperative analgesic efficacy of ketamine infusion alone in cancer breast surgeries.

METHODS

Ninety patients aged between 18 and 65 years and undergoing elective cancer breast surgery were included in this prospective randomized, double-blind study. Group K received ketamine 0.5.ßmg.kg^...1 bolus then 0.12.ßmg.kg^...1.h^...1 infusion for the first 24.ßhours postoperatively. Group KM: received ketamine 0.5.ßmg.kg^...1 and Mg sulfate 50.ßmg.kg^...1, then ketamine 0.12.ßmg.kg^...1.h^...1 and Mg sulfate 8.ßmg.kg^...1.h^...1 infusions for the first 24.ßhours postoperative. The primary outcome was the morphine consumption in the first 24.ßhours postoperative, while the secondary outcomes were: intraoperative fentanyl consumption, NRS, side effects, and chronic postoperative pain.

RESULTS

Group KM had less postoperative opioid consumption (14.12.ß...ß5.11.ßmg) than Group K (19.43.ß...ß6.8.ßmg). Also, Group KM had less intraoperative fentanyl consumption. Both groups were similar in postoperative NRS scores, the incidence of side effects related to opioids, and chronic neuropathic pain.

CONCLUSION

Adding Mg to ketamine infusion can safely improve intraoperative and postoperative analgesia with opioid-sparing effect in cancer breast surgery.

The protective effect of magnesium sulfate on placental inflammation via suppressing the NF-κB pathway in a preeclampsia-like rat model

Abnormal placental inflammation has a role in the pathophysiology of preeclampsia. Magnesium sulfate (MgSO₄) has anti-inflammatory properties and is a fetal neuroprotective agent. MgSO₄ is often used to treat severe preeclampsia; however, the specificmechanisms of action underlyingthistherapeutic effect remain unclear. The objective of this study was to investigate the effects of MgSO₄ (270 mg/kg) on placental inflammation in a rat model of lipopolysaccharide (LPS; 1.0 µg/kg)-induced preeclampsia. Compared to normal pregnant rats, LPS-treated pregnant rats had higher blood pressure, proteinuria, and expression of the anti-angiogenic factor sFlt-1 and the pro-inflammatory factors interleukin-1β (IL-1β) and IL-12 in placental tissue. LPS-treated pregnant rats had placental insufficiency, poor fetal outcomes, and significantly decreased expression of the anti-inflammatory factors apolipoprotein E (APOE) and IL-10 in placental tissue. MgSO₄ treatment had favorable effects on maternal and fetal outcomes. MgSO₄ treatment improved placental function by repressing an exaggerated inflammatory response in the placenta and promoting angiogenesis via the NF-κB pathway. These findings suggest MgSO₄ has a potential role in the prevention of preeclampsia and in the treatment of mild and moderate preeclampsia.

Magnesium Sulfate Use in Pregnancy for Preeclampsia Prophylaxis and Fetal Neuroprotection: Regimens in High-Income and Low/Middle-Income Countries

Magnesium sulfate is one of the most commonly used medications in obstetrics, most notably for the prevention of eclamptic seizures and fetal neuroprotection of the extremely preterm neonate. Pharmacokinetic and pharmacodynamic studies have demonstrated a variety of IV and IM regimens are effective for these indications. Existing models and data can be used to tailor treatment regimens to increase coverage in poor resource areas, maximize efficacy and minimize toxicity for patients of different weights and renal function.

Association of antenatal magnesium sulfate with reduced late-onset sepsis in extreme preterm infants

OBJECTIVES

Neonatal intensive care has changed extensively over the last decades resulting in improved survival of extreme preterm infants. However, improved survival is associated with prolonged hospitalization, mechanical ventilation and use of invasive devices, which are all predisposing factors for LOS. LOS is known to increase short- and long-term morbidities resulting in impaired neurodevelopmental outcome. Besides treatment with antibiotics and supportive care, there is an unmet need for adjunctive therapies to prevent neonatal sepsis and hereby improve outcome.

METHODS

In a retrospective single-center design, we explored underlying pre-, peri- and postnatal factors in extreme preterm infants with and without LOS to potentially identify future strategies in the prevention of LOS in these infants.

RESULTS

Associations formerly published could be confirmed, such as lower birth weight, longer duration of respiratory support, parenteral nutrition and NICU stay and a higher incidence of almost all neonatal morbidities. A new interesting finding was the fact that infants with LOS received more antenatal magnesium sulfate (p = 0.002). After nearest neighbor matching based on birth weight, gestational age, gender and multiplicity increased duration of parenteral nutrition and NICU stay, the incidence of PVL remained significantly different between the two groups (LOS/no LOS), but also the association between antenatal magnesium sulfate administration and less LOS held true (p = 0.004).

CONCLUSION

In this study, extreme preterm infants receiving antenatal magnesium sulfate developed less LOS. Whether this is merely an associative factor reflecting illness severity or an interesting link for new preventive strategies for LOS, should be further explored.

The Effect of the Magnesium Sulfate in Ultrasound-Guided Quadratus Lumborum Block on Postoperative Analgesia: A Randomized Controlled Trial

INTRODUCTION

Quadratus lumborum block (QLB) has proven to be an effective analgesic technique in various abdominal surgeries. Magnesium sulfate as an adjuvant in different nerve blocks has been reported. The aim of this study was to assess the efficacy of magnesium sulfate as an adjuvant to ropivacaine in an ultrasound-guided QLB for postoperative analgesia in laparoscopic gynecologic surgery.

METHODS

Ninety patients belonging to American Society of Anesthesiologists (ASA) physical status I or II, aged between 40 and 60 years, scheduled for laparoscopic gynecologic surgery were enrolled. Patients were divided into three groups and received bilateral quadratus lumborum block: ropivacaine group (group N, 0.375% ropivacaine 40 ml + normal saline 4 ml), magnesium sulfate group (group M, 0.375% ropivacaine 40 ml + 10% magnesium sulfate 4 ml), and control group (group C, normal saline 44 ml). Visual analogue scale (VAS) at rest and during activity at 4, 6, 12, 24, and 48 h postoperatively, consumption of morphine, the time of first analgesic request, frequency of rescue analgesia, satisfaction with postoperative analgesia, and any side effects were recorded.

RESULTS

VAS scores in groups M and N were significantly lower than in group C at 4 and 6 h postoperatively (P < 0.001). VAS scores were lower in group M at 12 and 24 h postoperatively compared to groups N and C (P < 0.05). The mean total morphine consumption was significantly lower in group M than in groups N and C (P < 0.001). The mean time to the first patient-controlled analgesia (PCA) bolus was significantly prolonged in group M compared to group C (P < 0.05). The satisfaction with postoperative analgesia of group M was superior to that of groups N and C (P < 0.05). There was no significant difference in side effects among the three groups.

CONCLUSION

Magnesium sulfate as an adjuvant to ropivacaine in ultrasound-guided QLB prolongs the duration of analgesia, decreases analgesic requirements, and improves patient satisfaction without significant side effects.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR1900027066.

Assessment of Magnesium Sulfate Infusion in Combination with Ketorolac for the Pain Management in Intertrochanteric Fractures; A Randomized Clinical Trial

Objectives

Intertrochanteric fracture is a common fracture that mainly occurs in the elderly. Diverse pain management strategies have been applied; however, considering the age of the patients, analgesia-related complications should be concisely considered. The current study aims to evaluate the efficacy and adverse effects of Ketorolac plus placebo versus Ketorolac plus magnesium sulfate for pain management in intertrochanteric fractures.

Methods

The current randomized clinical trial has been conducted on 60 patients with intertrochanteric fractures assigned into two groups of treatment with Ketorolac (30 mg) plus placebo (n=30) versus Ketorolac (30 mg) plus magnesium sulfate (15 mg/kg) (n=30). Pain scores using the visual analog scale (VAS), hemodynamic parameters, and complications (nausea and vomiting) were assessed at baseline and within 20, 40, and 60 minutes after the interventions. Additional morphine sulfate requirements were compared between the groups.

Results

Demographic characteristics in both groups were similar (P>0.05). All the assessments showed statistically significantly less pain severity in the magnesium sulfate/Ketorolac group (P<0.05), except for the baseline assessments (P=0.873). The two groups did not differ regarding hemodynamic parameters, nausea, and vomiting complaints (P>0.05). Although the frequency of additional morphine sulfate requirement was not different between the groups (P=0.06), the administered dose of morphine sulfate was significantly higher in those treated with ketorolac/placebo (P=0.002).

Conclusion

Based on the findings of this study, Ketorolac alone or in combination with magnesium sulfate led to significant pain reduction in patients with intertrochanteric fractures admitted to the emergency ward; however, the combination therapy had superior outcomes. Further studies are strongly recommended.

Critical Hypermagnesemia in Preeclamptic Women Under a Magnesium Sulfate Regimen: Incidence and Associated Risk Factors

Magnesium sulfate is used as prophylaxis and treatment of severe preeclampsia/eclampsia, albeit its safety and toxicity are a concern. We designed this study to estimate the incidence of critical hypermagnesemia in severely preeclamptic women under a magnesium sulfate regimen at 8 h following its administration and to identify the associated risk factors as the primary outcomes. Also, secondary outcomes were to compare baseline characteristics, laboratory findings, and maternal-neonatal complications stratified by the baseline serum magnesium (Mg²⁺) in those women, and to assess the degree of agreement between patellar reflex and serum Mg²⁺ concentration 8 h following magnesium sulfate administration. We conducted a retrospective study including severely preeclamptic women receiving magnesium sulfate from June 2016 to May 2021. We enrolled 429 women in the study. Two-hundred sixty-one (60.8%) of the included women developed critical hypermagnesemia. Preeclamptic women with high baseline serum Mg²⁺ concentration demonstrated significantly affected renal functions, hepatic transaminase activities, and low platelet count as well as more reported maternal complications compared to those with low baseline serum Mg². Multivariable logistic regression revealed that a lower gestational age, a higher uric acid concentration, and a higher baseline serum Mg²⁺ concentration were independently associated with an increased risk of critical hypermagnesemia. The agreement between deep tendon reflex assessment and serum Mg²⁺ concentration was slight although not significant. The maternal-neonatal outcomes were non-significant in women with critical hypermagnesemia. More vigilant monitoring through assessment of both serum Mg²⁺ concentration and deep tendon reflex should be considered especially in high-risk women.

Clinical efficacy of magnesium sulfate injection in the treatment of masseter muscle trigger points: a randomized clinical study

Objective

Myofascial pain syndrome with trigger points is the most common cause of nonodontogenic pain. Although injection of the trigger points is the most effective pain reduction treatment, many patients exhibit recurrence after a short period. Therefore, the aim of the current study was to evaluate the clinical efficacy of magnesium sulfate injections in the treatment of the masseter muscle trigger points when compared to saline injections.

Material and method

This study randomly (1:1) assigned 180 patients to one of two treatment groups based on whether their trigger points were injected with 2 ml of saline or magnesium sulfate. Pain scores, maximum mouth opening (MMO), and quality of life were measured at the pre-injection and 1, 3, and 6 months post-injection.

Results

The pain scores were significantly higher in the saline group during all follow-up assessments, whereas the MMO was significantly higher in the magnesium sulfate group up to 3 months of follow-up (p < 0.001). However, the difference in MMO ceased to be statistically significant after 6 months of follow-up (p = 0.121). Additionally, the patient’s quality of life score was significantly higher in the magnesium sulfate group compared to the saline group (p < 0.001).

Conclusion

Injection of magnesium sulfate is an effective treatment measure for myofascial trigger points. However, further studies with a proper design addressing the limitations of the current study are necessary.

ClinicalTrials: org (ID: NCT04742140) 5/2/2021.

Betamethasone use and risk factors for pulmonary edema during the perinatal period: a single-center retrospective cohort study in Japan

Background

A few studies have reported that maternal administration of antenatal corticosteroids increased the risk of pulmonary edema (PE). However, despite the increasing usage rate of betamethasone as antenatal corticosteroid, maternal administration of betamethasone as a risk factor for PE has not been well studied. This study aimed to evaluate how maternal backgrounds and complications, tocolytic agents, and betamethasone affect the incidence of PE during the perinatal period and determine the risk factor for PE.

Methods

This was a single-center retrospective cohort study in Kurashiki, Japan. The study subjects were patients who had been admitted to our hospital for perinatal management including pregnancy, delivery and puerperium between 2017 and 2020. The primary outcome measure was defined as the incidence of PE during hospitalization. First, in all study subjects, Cox proportional hazards model was used to determine the risk factor for PE during the perinatal period. Next, using propensity score matching, we divided the patients into the betamethasone and betamethasone-free groups and examined the association between betamethasone use and the incidence of PE with Cox proportional hazards model.

Results

During the study period, 4919 cases were hospitalized, and there were 16 PE cases (0.3%). In all analyzed subjects, the occurrence of PE was significantly associated with preeclampsia (hazard ratio 16.8, 95% confidence intervals (CI) 5.39–52.7, P < 0.001) and the combined use of the tocolytic agents such as ritodrine hydrochloride and magnesium sulfate, and betamethasone (hazard ratio 11.3, 95% CI 2.66–48.1, P = 0.001). In contrast, after propensity score matching, no statistically significant difference was found between the betamethasone and betamethasone-free groups in the incidence of PE (hazard ratio 3.19, 95% CI 0.67–15.3, P = 0.145).

Conclusions

A combined use of tocolytic agents and antenatal corticosteroids such as betamethasone may be an independent risk factor for PE during the perinatal period. On the other hand, betamethasone use alone may not be associated with the incidence of PE. When tocolytic agents and betamethasone are administrated to pregnant women, it is important to pay attention to the appearance of maternal respiratory symptoms.

Magnesium sulfate administration in difficult laryngoscopy: An effective and safe method

PURPOSE

Difficult laryngeal exposure during laryngeal microsurgery and laser surgery is a major concern for otolaryngologists. This study evaluated the efficacy and safety of magnesium sulfate administration in difficult laryngeal exposure patients.

STUDY DESIGN

Quasi-experimental design.

MATERIALS AND METHODS

Forty adult patients scheduled for laryngeal microsurgery with difficult laryngeal exposure according to Cormack-Lehane (CL) classification were included. Magnesium sulfate 50% (20-30 mg/kg) was administered as a bolus injection. Laryngeal exposure and hemodynamic stability were evaluated before and after the intervention.

RESULTS

CL grading was shown a statistically significant improvement after magnesium sulfate administration. There are no clinically significant changes in the mean arterial pressure, heart rate, and oxygen saturation levels in the patients who received magnesium sulfate for better laryngeal exposure.

CONCLUSION

Magnesium sulfate is an effective and safe drug for better viewing in difficult laryngeal exposure patients.

Modulatory effect of two regimens of magnesium sulfate on the systemic inflammatory response in pregnant women with imminent eclampsia

OBJECTIVE

This study compared the modulatory effect of two intravenous magnesium sulfate (MgSO₄) regimens on the systemic inflammatory response in pregnant women diagnosed with imminent eclampsia.

STUDY DESIGN

In a single-blind cross-sectional study, 33 women were allocated according to the Zuspan (n = 16) and Sibai (n = 17) MgSO₄ regimens, and treated for 24 h. Blood samples were collected pre-administration of the loading dose, at 24 h of the maintenance dose of MgSO₄, and at 48 h, when patients were without treatment. Plasma was used to determine interleukin (IL)-1 beta (IL-1β), IL-6, IL-10, tumor necrosis factor-alpha (TNF-α), heat shock protein (Hsp70), and heme oxygenase-1 (HO-1) by ELISA.

RESULTS

The treatment with the Zuspan's regimen didn't change plasma concentrations of TNF-α, IL-10, and Hsp70 in the three-time points studied. However, it decreased IL-1β at 24 h and 48 h and IL-6 at 48 h, and increased HO-1 concentration at 48 h. On the other hand, compared to the pre-treatment period, Sibai's regimen induced a significant decrease in TNF-α, IL-1β, IL-6, and Hsp70, while increased HO-1 levels both at 24 h and 48 h and, IL-10 concentration at 48 h.

CONCLUSIONS

Sibai's regimen determined an early and efficient immunoregulatory effect on systemic inflammatory response in preeclampsia, suggesting that the maintenance dose of two grams of MgSO₄ was better than one gram in the treatment of imminent eclampsia.

Efficacy of dexmedetomidine versus magnesium sulfate as an adjuvant to intraperitoneal bupivacaine in pediatric laparoscopic surgery: a randomized clinical trial

BACKGROUND

We evaluated the efficacy of dexmedetomidine versus magnesium sulfate as an adjuvant to intraperitoneal (IP) bupivacaine in pediatric laparoscopic inguinal herniorrhaphy.

METHODS

Ninety-seven male children, ASA I-II, 1-6 years old, undergoing laparoscopic inguinal herniorrhaphy, were randomized to receive before peritoneal insufflation, IP 2 mg.kg-1 bupivacaine 0.5% combined with either 1 μg.kg-1 of dexmedetomidine (Group D), 30 mg.kg-1 of magnesium sulfate (Group M), or normal saline (Group C). All tested drugs were diluted to the volume of 10 mL with normal saline. FLACC pain scores, need for rescue analgesics, time to flatus and first stool, emetic events, adverse effects, functional recovery, and parents' satisfaction were recorded for the first 48 h postoperatively.

RESULTS

FLACC scores were significantly higher in Group C than in the other two groups at 6, 8, 12, 18, 24, and 48 hours after surgery with no differences between Groups D and M. Rescue analgesia was significantly higher in Group C with none of the children in Groups D and M requiring rescue analgesia (p = 0.001). Times to first flatus and stool, emetic events, and adverse effects did not differ among groups. Times to return to normal functional activity were comparable in all groups. Parents' satisfaction was greater in Groups D and M than in Group C (p = 0.026).

CONCLUSION

Dexmedetomidine and magnesium sulfate added to IP bupivacaine improved the analgesia afforded by bupivacaine in the first two postoperative days in children scheduled for laparoscopic herniorrhaphy.

Therapeutics effects of inhaled magnesium sulfate combined with adrenergic beta-2 agonist on children with acute asthma: Systematic review and meta-analysis

AIM

To review the evidence on the effectiveness of inhaled magnesium sulfate (MgSO4) combined with beta-2 (B2) agonist as compared to inhaled B2 agonist alone in treating pediatric patients with moderate to severe asthma attacks METHODS: The search was conducted on five electronic databases namely the Cochrane Central Register of Controlled Trials (CENTRAL), Medline, PubMed, Science Direct, and Google Scholar.

RESULTS

Eight trials were included in the review. All studies involved a total of 1585 children aged 2-17 years with moderate to severe asthma attacks. The risk of bias was assessed using the Cochrane risk-of-bias tool for randomized trials. Three studies that assessed the effect of inhaled MgSO4 as adjunctive therapy on vital signs revealed no effect of inhaled MgSO4 on vital signs (SMD -0.11, 95% CI 0.27-0.04, p = 0.16, I² = 68%). Two studies that assessed the effect of inhaled MgSO4 as adjunctive therapy on asthma severity score (ASS) revealed no effect of inhaled MgSO4 on ASS (SMD 0.22, 95% CI 0.01-0.44, Z = 2.01, p = 0.04, I² = 88%). Two studies that assessed the effect of inhaled MgSO4 as adjunctive therapy on peak expiratory flow rate (PEFR) revealed a large effect of B2 agonist alone on PEFR (SMD 2.02, 95% CI 0.83-3.2, p < 0.001, I² = 98%).

CONCLUSION

This review does not support the use of inhaled MgSO4 as adjunctive therapy to B2 agonist for asthmatic children.

Fetal Neuroprotective Mechanism of Maternal Magnesium Sulfate: Proteomic Analysis

Mg supplementation has been shown to protect preterm fetuses from white and gray matter damage, but the mechanism is unclear. The purpose of this study was to study the effect of maternal inflammation on the overall protein panel of the fetal rat brain, as well as the neuroprotective effect of magnesium-sulfate (MG). Pregnant rats at e20 (n = 6, 18 total) received injections of i.p. lipopolysaccharide (LPS) 500 ug/kg or control saline (SAL) at time 0. Dams were randomized to treatment with s.c. MG (270 mg/kg loading followed by 27 mg/kg q20 min) or saline (SAL) from -2 to +2 h, followed by an additional injection of MG (270 mg/kg) at +2 h. At 4 h after LPS administration, fetal brains were collected from the 3 treatment groups (LPS/SAL, LPS/MG, SAL/SAL) and analyzed by proteomic technique. LPS significantly decreased fetal brain complement C3, alpha-1-antiproteinase, metallothionein-3, alpha-2-macroglobulin, neurosecretory protein VGF, glutathione S-transferase mu 2, fam91a1, cnot7, mitogen-activated protein kinase levels, and significantly increased fetal brain Hbg1, while MG treatment normalized these measures to normal values. Maternal inflammation may cause brain injury via pathways other than the activation of neurotoxic cytokines; this effect could be due to increased/decreased production of certain proteins associated with securing oligodendrocytes, encouraging neuronal growth in the brain, or protecting against cerebral ischemia. MG's neuroprotective activity may be achieved by modifying the effect of LPS on proteins involved in early brain development.

The effect of magnesium sulfate on emergence agitation in children undergoing general anesthesia: A systematic review and meta-analysis

STUDY OBJECTIVE

Emergence agitation (EA) is a common complication in pediatric patients after general anesthesia. The effectiveness of magnesium sulfate in decreasing the incidence of EA in children remains controversial. Therefore, a systematic review and meta-analysis was performed to assess the efficacy of magnesium sulfate in preventing EA in pediatric patients following general anesthesia.

DESIGN

Systematic review and meta-analysis.

SETTING

PubMed, Embase, Web of Science, and Cochrane Library were searched to identify eligible randomized controlled trials from their respective database inception dates to June 30, 2021.

PATIENTS

Pediatric patients (< 18 years old) undergoing general anesthesia.

INTERVENTIONS

Intravenous administration of magnesium sulfate.

MEASUREMENTS

The primary outcome of the meta-analysis was EA incidence. The risk of bias of the included studies was evaluated using the revised Cochrane risk of bias tool for randomized trials (RoB 2.0). Grading of Recommendations, Assessment, Development, and Evaluation was applied to assess the level of certainty.

MAIN RESULTS

Eight studies with 635 participants were identified. The forest plot revealed no significant difference in the incidence of EA between patients treated with magnesium sulfate and the control group (risk ratio = 0.69, 95% confidence interval [0.44, 1.07]; P = 0.10, I² = 74%, moderate level of certainty). Additionally, magnesium sulfate did not reduce postoperative pediatric anesthesia emergence delirium scores but prolonged the emergence time. No significant differences were observed in postoperative complications (nausea, vomiting, laryngospasm, breath-holding, coughing, oxygen desaturation, and cardiac arrhythmias).

CONCLUSIONS

Administration of magnesium sulfate during general anesthesia did not affect the occurrence of EA in pediatric patients. However, magnesium sulfate can prolong the emergence time without adverse effects. PROSPERO registration number: CRD42021252924.

Effects of Combined Sertraline and Magnesium in Rat Atrium

The objective of this study is to determine the synergistic effects of an antioxidant ion Mg⁺², combined with selective serotonin reuptake inhibitor sertraline, in treatment or prevention of major depression and regulation of inotropic effect in the early postoperative period. Adult male 40 Wistar albino rats were randomly divided into 6 groups. Three to 4-mm long atrium strips were placed in organ bath, tension was adjusted to 2 g. Isometric contractions were induced with 10^-3 M adrenaline. Group 1 was the control group, cumulative sertraline was given to group 2, cumulative MgSO₄ to group 3, combined cumulative sertraline and MgSO₄ to group 4, intraperitoneal sertraline injection for 29 days to group 5, and intraperitoneal MgSO₄ injection for 14 days to group 6. Changes in weight, tensions, bleeding/clotting time, and biochemical findings were evaluated statistically. Isometric tension relationship between groups 1 and 3 was statistically significant after 4 mmol/L MgSO₄ (p < 0.05). A rapid inhibition of contraction was observed in group 4. Inhibition of spontaneous contractions of groups 5 and 6 was found to be statistically significant at close values, p < 0.05. When blood clotting times were compared, a statistically marked decrease was found in group 6, p < 0.05. Compared to control group, there was a significant decrease in blood lipids in group 4. While LDH and CK-MB increased from plasma enzymes in groups 5 and 6, no significant change was observed in NT-proBNP. Combined treatment of high dose MgSO₄ with antidepressants for pre or post-operative depression may cause fatal risks. Shortening clotting time may increase the risk of embolism and stroke. In order to reduce the risk of post-operative depression preoperatively, care should be taken when using magnesium combined with antidepressants and more studies are needed to be considered.

The addition of magnesium sulfate and borax to urea reduced soil NH3 emissions but increased N2O emissions from soil with grass

Nitrogen (N) use efficiency can be increased by the addition of substances to urea. Magnesium sulfate (MgSO₄) and boron were considered as plant nutrients, while zeolite was used as soil conditioner. The addition of these substances may affect soil NH₃ and N₂O emissions, by increasing N use efficiency. We conducted an 30 days incubation experiment with ryegrass using fertilizer treatments (12 g N m^-2) as follows: urea (U); urea + MgSO₄ (UM); urea + MgSO₄ + borax (UMB); zeolite + urea + MgSO₄ (Z-UM); and zeolite + urea + MgSO₄ + borax (Z-UMB). We measured NH₃ and N₂O emissions and the aboveground N uptake of ryegrass. Cumulative NH₃ emissions of UM, UMB, Z-UM and Z-UMB were 10%, 53%, 21% and 58% lower than U, respectively, while their N₂O emissions were 32%, 133%, 43% and 72% higher than U, respectively. Aboveground N uptake of UM, UMB, Z-UM and Z-UMB were 9%, 6%, 12% and 13% higher than U, respectively. Overall, we suggest that the addition of MgSO₄ and borax were effective in reducing NH₃ emissions and potentially increase plant N uptake. However, the risk of higher denitrification and N₂O emissions also needs to be considered. This study reveals the considerable effect of MgSO₄ and borax in soil N cycles. Future research should evaluate how the application of urea + MgSO₄ + borax effects gaseous emissions and crop yield of dicotyledons and in drier soil conditions.

Analgesic Efficacy of Addition of Magnesium Sulfate to Bupivacaine in Wound Infiltration Technique in Perianal Surgeries

BACKGROUND

In peripheral nerve blocks, magnesium sulfate is an excellent adjuvant to local anesthetics. The use of magnesium sulfate as an adjuvant in wound infiltration for postoperative analgesia needs to be investigated.

AIMS

This study was conducted to evaluate the analgesic efficacy of magnesium sulfate as an adjuvant when added to bupivacaine in wound infiltration technique in perianal surgeries.

SETTINGS AND DESIGN

This was a prospective, randomized, double-blind study.

MATERIALS AND METHODS

Sixty patients undergoing perianal surgeries were randomly divided into two groups, Group M and Group C. Following perianal surgery, Group M patients received a local wound infiltration of injection magnesium sulfate 750 mg (1.5 mL of injection 50% magnesium sulfate) added to 0.5% bupivacaine 13.5 mL making a total volume of 15 mL, whereas Group C patients received a local wound infiltration of injection 0.5% bupivacaine 13.5 mL and 1.5 mL normal saline. Postoperative vitals and pain scores were assessed.

STATISTICAL ANALYSIS USED

Student's t-test for normally distributed continuous data, Mann-Whitney U-test for ordinal data, and Chi-square test or Fisher's exact test, whichever is appropriate for categorical data, were used.

RESULTS

The magnesium sulfate group had a lower postoperative pain score, a longer duration of postoperative analgesia, and a lesser number of rescue analgesic doses in the first 24 h.

CONCLUSION

We conclude that magnesium sulfate is an effective adjuvant to bupivacaine for wound infiltration in terms of postoperative analgesia quality and duration following perianal surgeries.

Magnesium sulfate reduces vascular endothelial cell apoptosis in rats with preeclampsia via the miR-218-5p/HMGB1 pathway

OBJECTIVE

This study aims to investigate the mechanism by which magnesium sulfate regulates the miR-218-5p/HMGB-pathway-mediated apoptosis of vascular endothelial cells (VECs) in rats with preeclampsia (PE).

METHODS

Twenty pregnant rats were randomly divided into four groups: normal, PE, MgSO₄, and high-mobility group protein B1 (HMGB1)-agomir groups. On the 14^th day of each rat's pregnancy, endotoxin was used to establish a PE model in the PE, MgSO₄, and HMGB1-agomir groups. Then, the MgSO₄ and HMGB1-agomir groups were treated with magnesium sulfate. Finally, HMGB1 overexpression was performed only in the HMGB1-agomir group. The rats' urinary protein content and systolic blood pressure at 24 h were detected on the 11^th, 13^th, 15^th, 17^th, and 19^th day of pregnancy.

RESULTS

Compared with the PE group, 24-h urinary protein content, blood pressure, VEC apoptosis rate, apoptosis marker levels, and HMGB1 expression decreased while miR-218-5p levels increased in the MgSO₄ group. The dual-luciferase assay revealed that HMGB1 can be targeted and regulated by miR-218-5p. Compared with the MgSO₄ group, 24-h urinary protein content, blood pressure, VEC apoptosis rate, apoptosis marker levels, and HMGB1 expression increased while miR-218-5p levels decreased in the HMGB1-agomir group.

CONCLUSION

MgSO₄ reduces VEC apoptosis in PE rats via the miR-218-5p/HMGB1 pathway and thus plays a role in treating PE.

The effects of nebulized ketamine and intravenous magnesium sulfate on corticosteroid resistant asthma exacerbation; a randomized clinical trial

BACKGROUND AND AIMS

Asthma exacerbation is defined as an acute attack of shortness of breath with more than 25% decrease in morning peak flow compared to the baseline on 2 consecutive days, which requires immediate standard therapy. The majority of asthmatic patients are considered to be steroid-sensitive; however, corticosteroid-resistant asthma is a subset of asthma with poor response to corticosteroids and is responsible for frequent hospital admissions. In this study we aimed to compare the effects of two enhancing strategies, the nebulized ketamine and IV magnesium sulfate, in treatment of severe steroid resistant asthma.

MATERIALS AND METHODS

This double-blind randomized clinical trial was conducted on patients who presented to a referral clinic in Alborz, Iran. Using random allocation, patients were divided into two groups. The first group was treated with nebulized ketamine and the second group was treated with intravenous magnesium sulfate. Peak expiratory flow rates were assessed before the intervention, 30 and 60 min after the intervention and compared with the aid of SPSS software.

RESULTS

The Peak expiratory flow rates before the intervention, 30 min and 60 min after the intervention was statistically significantly different in both ketamine and magnesium sulfate groups. Peak expiratory flow rates change between 0 and 60 min were 29.4 and 15.2% in the ketamine and magnesium sulfate group respectively. Although the ketamine group showed much higher increase in mean PEFR compared to the MgSO4 groups, there was no statistically significant difference across both groups.

CONCLUSION

Our study concluded that combined with standard therapy, both ketamine and IV magnesium sulfate are effective agents in the improvement of PEFR in patients with acute severe asthma that failed to respond to traditional therapies. However, there were no statistically significant difference between the two groups.

Phosphorus mobilization in unamended and magnesium sulfate-amended soil monoliths under simulated snowmelt flooding

Enhanced release of phosphorus (P) from soils with snowmelt flooding poses a threat of eutrophication to waterbodies in cold climatic regions. Reductions in P losses with various soil amendments has been reported, however effectiveness of MgSO₄ has not been studied under snowmelt flooding. This study examined (a) the P release enhancement with flooding in relation to initial soil P status and (b) the effectiveness of MgSO₄ at two rates in reducing P release to floodwater under simulated snowmelt flooding. Intact soil monoliths were collected from eight agricultural fields from Southern Manitoba, Canada. Unamended and MgSO₄ surface-amended monoliths (2.5 and 5.0 Mg ha^-1) in triplicates were pre-incubated for 7 days, then flooded and incubated (4 °C) for 56 days. Pore water and floodwater samples collected at 7-day intervals were analyzed for dissolved reactive P (DRP), pH, Ca, Mg, Fe and Mn. Redox potential (Eh) was measured on each day of sampling. Representative soil samples collected from each field were analyzed for Olsen and Mehlich 3-P. Simulated snowmelt flooding enhanced the mobility of soil P with approximately 1.2-1.6 -fold increase in pore water DRP concentration from 0 to 21 days after flooding. Mehlich-3 P content showed a strong relationship with the pore water DRP concentrations suggesting its potential as a predictor of P loss risk during prolonged flooding. Surface application of MgSO₄ reduced the P release to pore water and floodwater. The 2.5 Mg ha^-1 rate was more effective than the higher rate with a 21-75% reduction in average pore water DRP, across soils. Soil monoliths amended with MgSO₄ maintained a higher Eh, and had greater pore water Ca and Mg concentrations, which may have reduced redox-induced P release and favored re-precipitation of P with Ca and Mg, thus decreasing DRP concentrations in pore water and floodwater.

Analgesic effect of magnesium sulfate during total intravenous anesthesia: randomized clinical study

Introduction and objective

: Opioids have usually been used as intraoperative analgesic components, regardless of the many adverse effects they are associated with, such as nausea, vomiting, respiratory depression, and hyperalgesia. Several approaches have been investigated to reduce doses used, and magnesium sulfate has been shown to be a valuable analgesic adjunct. The main objective of the present trial was to evaluate the effectiveness of magnesium sulfate as the chief intraoperative analgesic, and the secondary objectives were to assess propofol consumption, postoperative analgesia, and intraoperative hemodynamic stability.

Methods

In this prospective, double-blind trial, 50 patients scheduled to undergo post-bariatric abdominoplasty under general intravenous anesthesia were divided into two groups, to receive remifentanil or magnesium sulfate as intraoperative analgesic. Fentanyl 1 µg kg^-1 was the rescue analgesic.

Results

Among the patients in the group receiving Magnesium Sulfate (MSG), 64% did not need supplemental analgesia and none of the patients in the Remifentanil Group (RG) required fentanyl. MSG patients showed propofol consumption 36.6% higher (guided by the Bispectral Index – BIS). MSG patients consumed significantly less ephedrine (mean ± SD) than RG patients, respectively 1.52 ± 4.38 mg and 10 ± 10.39 mg, p < 0.001. Mean values of blood concentrations of magnesium were comparable to values previously described in the literature.

Conclusion

Magnesium sulfate is a safe and effective option for intraoperative analgesia, when avoiding or decreasing opioid use is required.

Efficacy of Antenatal Magnesium Sulfate for Neuroprotection in Extreme Prematurity: A Comparative Observational Study

Background

Survival of preterm infants has improved drastically. In addition to significant contribution to neonatal mortality, impact of prematurity among survivors may continue through life impairing long-term physical life through neuro-disability and increased risk of cerebral palsy. Maternal administration of magnesium sulfate prior to impending preterm birth is an effective strategy to reduce neuromorbidity.

Aim

To investigate the effectiveness of antenatal magnesium sulfate for neuroprotection in preterm infants between 26 and 34 weeks in preventing early neonatal morbidity and mortality. Secondary objective was to assess any adverse events with the use of magnesium sulfate on the mother and neonate.

Method

This was a prospective observational comparative study for 2 years at our tertiary care hospital of 100 pregnant women who gave preterm births. Fifty infants each were born to mothers who were either not given MgSO₄ (Group 1) or given 4gm intravenous loading dose MgSO₄ (Group 2), preferably 4 h prior to preterm birth.

Results

Among all the preterm in our study, 81% delivered between 30 and 34 weeks. There was no significant difference in terms of maternal mortality or serious morbidity including postpartum hemorrhage, caesarian section rates or length of hospital stay among women receiving MgSO₄ versus no MgSO₄. Mild maternal side effects secondary to magnesium sulfate were experienced in 8% cases. There were no significant differences between both groups for low 5 min APGAR, need for NICU admission, neonatal convulsions, hyperbilirubinemia, necrotizing enterocolitis, periventricular leukomalacia and septicemia. There was a trend toward reduced risk in the magnesium sulfate group for need for mechanical ventilation and ongoing respiratory support, intraventricular hemorrhage, neonatal hypotension, hypothermia, length of NICU stay. IVH was less frequent and less severe in babies exposed to antenatal MgSO₄ (8%) as compared to non-MgSO₄ group (16%). Neonatal morbidities were more when antenatal MgSO₄ was given less than 4 h from delivery.

Conclusion

MgSO₄ is a safe drug to use in antenatal women at risk for impending preterm. Antenatal magnesium sulfate given to women in established preterm labor conferred significant neuroprotective advantage to the neonate. MgSO₄ also has protective effect on the need of invasive ventilatory support in preterm infants. Given the breadth of evidence in its favor, it is time for us to start using MgSO₄ in clinical practice for neuroprotective intent in all our extreme preterm births.

Efficacy of magnesium sulfate as an adjuvant to rocuronium in general anaesthesia: a meta-analysis

Objective

Magnesium sulfate is considered to be an effective adjuvant to rocuronium in general anaesthesia. We conducted a meta-analysis to clarify its efficacy.

Methods

We searched the PubMed, Embase, Web of Science, Cochrane Library, WanFang, Chinese Biomedical Literature, and China National Knowledge Infrastructure databases for randomized controlled trials (RCTs) of magnesium sulfate as an adjuvant to rocuronium from the start of the database establishment until May 2020.

Results

Eleven RCTs were analysed. The pooled meta-analysis showed that using magnesium sulfate as an adjuvant significantly shortened the onset time and prolonged the clinical duration of neuromuscular blockade by rocuronium compared with the control group without magnesium sulfate. However, there was no significant difference in recovery index of neuromuscular block between the magnesium and control groups. Furthermore, magnesium sulfate significantly increased the rates of excellent and clinically acceptable intubation conditions.

Conclusion

Adding magnesium sulfate to rocuronium during general anaesthesia can alter the neuromuscular parameters, including shortening the anaesthesia-onset time and prolonging the clinical duration, without significantly increasing the recovery time. Pretreatment with magnesium sulfate may also improve intubation conditions during general anaesthesia.

Early versus delayed administration of intravenous magnesium sulfate for pediatric asthma

OBJECTIVE

This study aims to describe and examine the factors associated with the early administration of intravenous magnesium sulfate (IV Mg) in children presenting to the pediatric emergency department (ED) for an asthma exacerbation.

METHODS

Retrospective cohort study of children aged 5-11 years who received IV Mg in the pediatric ED between September 1, 2018 and August 31, 2019 for management of an asthma exacerbation. Primary outcome was administration of IV Mg in ≤60 min from ED triage ('early administration'). Comparison of clinical management and therapies in children who received early versus delayed IV Mg and the factors associated with early administration of IV Mg were examined.

RESULTS

Early (n = 90; 31.6%) IV Mg was associated with more timely bronchodilators (47 versus 68 min; p ≤ 0.001) and systemic corticosteroids (36 versus 46.5 min; p ≤ 0.001). There was no difference between the two cohorts in returns to the ED within 72 h (1.1% versus 2.1%; p = .99) or readmissions within 1 week one week (2.2% versus 0.5%; p = .2). Hypoxia (aOR = 3.76; 95% CI = 2.02-7.1), respiratory rate (aOR = 1.04; 95% CI = 1.02-1.07), retractions (aOR = 2.21; 95% CI = 1.25-3.94), and prior hospital use for asthma-related complaints (aOR = 2.1; 95% CI = 1.16-3.84) were significantly associated with early IV Mg.

CONCLUSIONS

Early administration of IV Mg was associated with more timely delivery of first-line asthma therapies, was safe, and improved ED throughput without increasing return ED visits or hospitalizations for asthma.

Effect of magnesium sulfate in oxidized lipid bilayers properties by using molecular dynamics

Magnesium sulfate (MgSO₄) has been used as a protector agent for many diseases related to oxidative stress. The effect of MgSO₄ on the oxidized lipid bilayer has not yet been studied using molecular dynamics calculations. In this work, the effects of oxidation were evaluated by using a POPC membrane model at different concentrations of its aldehyde (-CHO) and hydroperoxide (-OOH) derivatives with and without MgSO₄. Several quantitative and qualitative properties were evaluated, such as membrane thickness, area per lipid, area compressibility modulus, snapshots after simulation finish, density distributions, time evolutions of oxidized group positions, and radial distributions of oxidized group concerning Mg. Results indicate that in the absence of MgSO₄ the mobility of oxidized groups, particularly –CHO, toward the surface interface is high. At a low oxidation level of the bilayer there is an increase in the compressibility modulus as compared to the unoxidized bilayer. MgSO₄, at a low oxidation level, tends to lessen the oxidation effects by lowering the dispersion in the distribution of oxidized species toward the membrane surface and the water region. However, MgSO₄ does not change the trends of decreasing membrane thickness and area compressibility modulus and increasing area per lipid upon oxidation. In this regard, MgSO₄ diminishes the electrostatic long-distance attractive interactions between the oxidized groups and the charged headgroups of the interface, owing to the Mg⁺² and SO₄^-2 screening effects and an electrostatic stabilization of the headgroups, preventing the pore formation, which is well-known to occur in oxidized membranes.

•

MgSO₄ in vitro restores oxidized membranes but its molecular mechanism is unclear.

•

MD simulations of oxidized lipid bilayers were performed with and without of MgSO₄.

•

A restriction in the mobility of oxidized groups is produced by MgSO₄.

•

Mg⁺² and SO₄⁼ produce screening effects on the oxidized membranes.

•

MgSO₄ produce a diminution of electrostatic long-distance attractive interactions.

Pharmacological torpor prolongs rat survival in lethal normobaric hypoxia

Resistance to hypoxia is one of the most prominent features of natural hibernation and is expected to be present in the pharmacological torpor (PT) that simulates hibernation. We studied resistance to lethal hypoxia (3.5% oxygen content) in rats under PT. To initiate PT, we used the previously developed pharmacological composition (PC) which, after a single intravenous injection, can induce a daily decrease in Tb by 7 °C-8 °C at the environmental temperature of 22 °C-23 °C. Half-survival (median) time of rats in lethal hypoxia was found to increase from 5 ± 0.8 min in anesthetized control rats to 150 ± 12 min in rats injected with PC, which is a 30-fold increase. Behavioral tests after PT and hypoxia, including the traveling distance, the number of rearing and grooming episodes, revealed that animal responses are significantly restored within a week. It is assumed that the discovered unprecedented resistance of artificially torpid rats to lethal hypoxia may open up broad prospects for the therapeutic use of PT for preconditioning to various damaging factors, treatment of diseases, and extend the so-called "golden hour" for lifesaving interventions.

MR T1 mapping for quantifying brain manganese deposition in type C hepatic encephalopathy rats

To evaluate magnetic resonance (MR) T1 mapping for quantifying brain manganese (Mn) deposition in type C hepatic encephalopathy (CHE) rats and to investigate the mechanism of magnesium sulfate (MgSO₄) therapy. Thirty Sprague-Dawley rats were randomly assigned into normal control group (NC, n = 6) and CHE groups (n = 24). Thioacetamide (TAA) was used for modeling CHE rats. CHE groups were further divided into 4 subgroups: TAA group, MgSO₄ low dose (Mg-L) group, MgSO₄ high dose (Mg-H) group and deionized water (DW) group (n = 6 for each group). TAA, Mg-L, Mg-H and DW groups were received intraperitoneal injections of 250 mg TAA/kg, twice a week for 8 weeks. Mg-L and Mg-H groups were orally received MgSO₄ of 124 and 248 mg/kg daily, respectively, for another 8 weeks (without TAA). MR T1 mapping was performed in NC, TAA, Mg-L, Mg-H and DW groups at various time points. T1 value and Mn content in basal ganglia, hippocampus, cerebral cortex and cerebellum were evaluated. Morris water maze (MWM) and narrow beat test (NBT) were utilized to evaluate rats' learning, memory and motor ability. Contents of interleukin-6 (IL-6), tumor necrosis factor-a (TNF-a) and calcium-binding adaptor 1 protein (Iba1) were evaluated. Reduced T1 values in basal ganglia, hippocampus and cerebral cortex (P < 0.01, P < 0.05 and P < 0.05, respectively); increased Mn content in basal ganglia, hippocampus and cerebral cortex (all P < 0.05); reduced times of head contacting with region of interest (ROI), reduced times of entrance into the target quadrant (both P < 0.05); increased NBT total time (P < 0.05); increased brain contents of IL-6 (P < 0.001), TNF-α (P < 0.01) and over-expression of Iba1 were found in TAA group compared to NC group. After treated by MgSO₄, increased T1 value and reduced Mn content in basal ganglia, hippocampus and cerebral cortex (all P < 0.01); increased times of head contacting with ROI, increased times of entrance into the target quadrant (both P < 0.05); reduced NBT total time (P < 0.01); reduced brain content of IL-6, TNF-α (both P < 0.05) and reduced expression of Iba1 were found. T1 values were negatively correlated with Mn contents in basal ganglia (r = - 0.834, P < 0.01), hippocampus (r = - 0.739, P < 0.05), cortex (r = - 0.801, P < 0.05) and cerebellum (r = - 0.788, P < 0.05). T1 mapping could quantify brain Mn deposition in CHE rats. MgSO₄ could improve cognition and motor ability of CHE rats by reducing brain Mn deposition, alleviating neurological inflammation and achieve the effective therapy for CHE. Mn may participate in the pathogenesis of CHE through neuroinflammation.

Protective Effects of Intravenous Magnesium Sulfate in Stroke Patients Receiving Amiodarone: A Randomized Controlled Trial

Anti-arrhythmic agents, like amiodarone, interfere at different stages of the ischemic stroke. However, amiodarone was accompanied with immunological pulmonary complications and adverse neurological effects. We hypothesize that magnesium sulfate in combination with amiodarone holds promise for stroke treatment. Thirty-six patients with confirmed diagnosis of ischemic stroke and atrial fibrillation who received bolus amiodarone were randomly assigned to magnesium sulfate every 24 h or similar volume of normal saline (as placebo) for 5 days. Various severity test scores were used to evaluate the symptoms. Routing biochemistry were also measured at days 1 and 5. Treatment with MgSO4 results in a significant reduction in serum levels of NGAL, Hb, T.Bill, IL-6, IL-8, SNSE, S100B, EGF, PAF, CRP and IgG. Also, MgSO4 treatment significantly improved the RASS, Candida, SOFA, NIHSS and APACHE scores. Moreover, reduction of IL-6, IL-8, SNSE, EGF and APACHE score and increase in RASS score were significantly higher in MgSO4 group compared with placebo. Intravenous administration of MgSO4 in amiodarone-treated stroke patients improved the inflammatory, immunological and neurological indicators and reduced disability in ICU-admitted AIS patients, suggesting that this treatment scheme may prevent amiodarone-induced complications in these patients.

Lidocaine combined with magnesium sulfate preserved hemodynamic stability during general anesthesia without prolonging neuromuscular blockade: a randomized, double-blind, controlled trial

Background

Lidocaine and magnesium sulfate have become increasingly utilized in general anesthesia. The present study evaluated the effects of these drugs, isolated or combined, on hemodynamic parameters as well as on the cisatracurium-induced neuromuscular blockade (NMB).

Methods

At a university hospital, 64 patients, ASA physical status I and II, undergoing elective surgery with similar pain stimuli were randomly assigned to four groups. Patients received a bolus of lidocaine and magnesium sulfate before the tracheal intubation and a continuous infusion during the operation as follows: 3 mg.kg^− 1 and 3 mg.kg^− 1.h^− 1 (lidocaine - L group), 40 mg.kg^− 1 and 20 mg.kg^− 1.h^− 1 (magnesium - M group), equal doses of both drugs (magnesium plus lidocaine - ML group), and an equivalent volume of isotonic solution (control - C group). Hemodynamic parameters and neuromuscular blockade features were continuously monitored until spontaneous recovery of the train of four (TOF) ratio (TOFR > 0.9).

Results

The magnesium sulfate significantly prolonged all NMB recovery features, without changing the speed of onset of cisatracurium. The addition of lidocaine to Magnesium Sulfate did not influence the cisatracurium neuromuscular blockade. A similar finding was observed when this drug was used alone, with a significantly smaller fluctuation of mean arterial pressure (MAP) and heart rate (HR) measures during anesthesia induction and maintenance. Interestingly, the percentage of patients who achieved a TOFR of 90% without reaching T1–95% was higher in the M and ML groups. Than in the C and L groups. There were no adverse events reported in this study.

Conclusion

Intravenous lidocaine plays a significant role in the hemodynamic stability of patients under general anesthesia without exerting any additional impact on the NMB, even combined with magnesium sulfate. Aside from prolonging all NMB recovery characteristics without altering the onset speed, magnesium sulfate enhances the TOF recovery rate without T1 recovery. Our findings may aid clinical decisions involving the use of these drugs by encouraging their association in multimodal anesthesia or other therapeutic purposes.

Trial registration

NCT02483611 (registration date: 06-29-2015).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01311-y.