The effects of magnesium sulfate therapy after severe diffuse axonal injury

Initial Serum Magnesium Level Is Associated with Mortality Risk in Traumatic Brain Injury Patients

BACKGROUND

Electrolyte disorder is prevalent in traumatic brain injury (TBI) patients. This study is designed to explore the association between initial serum magnesium levels and mortality of TBI patients.

METHODS

TBI patients recorded in the Medical Information Mart for Intensive Care-III database were screened for this study. Logistic regression analysis was used to explore risk factors for mortality of included TBI patients. The restricted cubic spline (RCS) was applied to fit the correlation between initial serum magnesium level and mortality of TBI.

RESULTS

The 30-day mortality of included TBI patients was 17.0%. Patients with first-tertile and third-tertile serum magnesium levels had higher mortality than those of the second tertile. Univariate regression analysis showed that the serum magnesium level was not associated with mortality. Unadjusted RCS indicated the relationship between serum magnesium level mortality was U-shaped. After adjusting confounding effects, multivariate regression analysis presented that serum magnesium level was positively associated with mortality.

CONCLUSION

TBI patients with abnormally low or high levels of serum magnesium both have a higher incidence of mortality. At the same time, a higher initial serum magnesium level is independently associated with mortality in TBI patients. Physicians should pay attention to the clinical management of TBI patients, especially those with higher serum magnesium levels.

N-methyl-D-aspartate receptor antagonists in improving cognitive deficits following traumatic brain injury: a systematic review

OBJECTIVE

To review the role of N-methyl-D-aspartate receptor (NMDAR) antagonists in managing post-TBI cognitive deficits.

METHODS

A search of PubMed, Embase, and Cochrane was conducted on Jan 12, 2021 without publication date or language restriction.

RESULTS

Forty-seven studies were included, involving 20 (42.6%) randomized controlled trials. Four (8.5%) studies had a low risk of bias (RoB), while 34 (72.3%) had unclear and nine (19.2%) had high RoB. Six NMDAR antagonists had been investigated: amantadine (n = 32), memantine (n = 4), magnesium (n = 4), traxoprodil (n = 3), selfotel (n = 2), and dextromethorphan (n = 2).

CONCLUSION

Although some benefits were observed, there are still some concerns regarding the efficacy and safety of NMDAR antagonists in improving post-TBI cognitive deficits. Further research is required to examine whether (i) these agents, notably amantadine, could accelerate cognitive improvement and shorten the hospital stay, (ii) these agents affect different cognitive domains/subdomains in the same direction, (iii) an optimal therapeutic time window exists, (iv) a member of this drug class can be proved to be effective without interfering in non-excitotoxic actions of glutamate, (v) they can be more effective as part of combination therapies or in particular subgroups of patients with TBI.

A randomized cohort study of the efficacy of PO magnesium in the treatment of acute concussions in adolescents

INTRODUCTION/STUDY OBJECTIVE

Concussions are becoming a growing concern in society today with one out of every five adolescents being affected. This accounts for 1.6 to 3.8 million emergency department visits annually. The current standard of care involves an initial period of mental rest with symptomatic care and symptom-based return to daily activities/sports. High dose IV magnesium has been proven to be neuroprotective in severe TBI. We hypothesized that oral magnesium replacement following a concussion will decrease the overall symptomatic period allowing a quicker return to functional baseline.

METHODS

We used a randomized cohort study involving patients aged 12-18 who presented within 48 h after a concussion. Our study design had a treatment arm including acetaminophen, ondansetron, and magnesium PO and a placebo arm of acetaminophen and ondansetron. We then utilized the Post- Concussion Severity Score (PCSS) to evaluate the extent of the patient's symptoms. This score was collected immediately prior to obtaining medications, 1 h, 48 h, and 120 h after starting the study. The study relied on outpatient follow up through phone conversations, and a Sports Medicine clinic locally.

RESULTS

Our data shows that there was a statistically significant decrease in the PCSS at 48 h (p = 0.016) in the magnesium group relative to the placebo treatment arm. This study does imply that magnesium supplementation has potential benefit in treatment of concussions acutely.

CONCLUSION

Oral magnesium replacement decreases symptoms acutely following a concussion and should be provided with symptomatic management following a concussion in the emergency setting.

Magnesium sulfate ameliorates carbon monoxide‑induced cerebral injury in male rats

Carbon monoxide (CO) has been shown to induce several cardiovascular abnormalities, as well as necrosis, apoptosis and oxidative stress in the brain. Magnesium sulfate (MS) has been shown to have beneficial activities against hypoxia in the brain. In the present study, the possible protective effects of MS against CO‑induced cerebral ischemia were investigated. For this purpose, 25 male Wistar rats were exposed to 3,000 ppm CO for 1 h. The animals were divided into 5 groups (n=5 in each group) as follows: The negative control group (not exposed to CO), the positive control group (CO exposed and treated with normal saline), and 3 groups of CO‑exposed rats treated with MS (75, 150 and 300 mg/kg/day) administered intraperitoneally for 5 consecutive days. On the 5th day, the animals were sacrificed and the brains were harvested for the evaluation of necrosis, apoptosis and oxidative stress. Histopathological evaluation revealed that MS reduced the number and intensity of necrotic insults. The Bax/Bcl2 ratio and malondialdehyde (MDA) levels were significantly decreased in a dose‑dependent manner in the MS‑treated rats compared to the positive control group, while a significant dose‑dependent increase in Akt expression, a pro‑survival protein, was observed. In addition, MS administration reduced pro‑apoptotic indice levels, ameliorated histological insults, favorably modulated oxidative status and increased Akt expression levels, indicating a possible neuroprotective effect in the case of CO poisoning. On the whole, the findings of this study indicate that MS may prove to be useful in protecting against CO‑induced cerebral injury.

Does magnesium sulfate have a role in the management of severe traumatic brain injury in civilian and military populations? A systematic review and meta-analysis

INTRODUCTION

Traumatic brain injury (TBI) is a significant cause of combat morbidity. Currently, the medical management of TBI is limited to supportive critical care. Magnesium sulfate has been studied as a potentially beneficial therapeutic agent.

METHODS

A systematic review and meta-analysis was undertaken, examining the role of magnesium in the management of severe TBI in adults. The primary outcome of the study was all-cause mortality, with secondary outcomes of Glasgow Outcome Score (GOS) and GCS. EMBASE, MEDLINE, CINAHL, WHO Trial Registry and the Cochrane Library database were systematically searched, with data included until 1 February 2017. Inclusion criteria were: human study; aged >13 years; randomised controlled trial; severe TBI. Exclusion criteria were: data collected prior to 1 January 2002; magnesium commenced >24 hours postinjury; magnesium therapy for <24 hours. Statistical analysis was conducted using Stata (V.13.1).

RESULTS

The pooled results of six studies found all-cause mortality not to be significantly different in the treatment group (RR 0.84, 95% CI 0.54 to 1.33; P=0.46) with an I² value of >70%. With regard to the secondary outcomes, no significant difference in GOS scores between treatment and control was demonstrated. GCS showed a significant improvement in the treatment group.

CONCLUSIONS

The meta-analysis found a lack of evidence for magnesium pharmacotherapy in severe TBI, although the data were noted to be conflicting and significantly heterogeneous. Further study is recommended to ascertain whether a therapeutic window exists for magnesium in severe TBI.

Serial Sampling of Serum Protein Biomarkers for Monitoring Human Traumatic Brain Injury Dynamics: A Systematic Review

BACKGROUND

The proteins S100B, neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP), ubiquitin carboxy-terminal hydrolase L1 (UCH-L1), and neurofilament light (NF-L) have been serially sampled in serum of patients suffering from traumatic brain injury (TBI) in order to assess injury severity and tissue fate. We review the current literature of serum level dynamics of these proteins following TBI and used the term "effective half-life" (t1/2) in order to describe the "fall" rate in serum.

MATERIALS AND METHODS

Through searches on EMBASE, Medline, and Scopus, we looked for articles where these proteins had been serially sampled in serum in human TBI. We excluded animal studies, studies with only one presented sample and studies without neuroradiological examinations.

RESULTS

Following screening (10,389 papers), n = 122 papers were included. The proteins S100B (n = 66) and NSE (n = 27) were the two most frequent biomarkers that were serially sampled. For S100B in severe TBI, a majority of studies indicate a t1/2 of about 24 h, even if very early sampling in these patients reveals rapid decreases (1-2 h) though possibly of non-cerebral origin. In contrast, the t1/2 for NSE is comparably longer, ranging from 48 to 72 h in severe TBI cases. The protein GFAP (n = 18) appears to have t1/2 of about 24-48 h in severe TBI. The protein UCH-L1 (n = 9) presents a t1/2 around 7 h in mild TBI and about 10 h in severe. Frequent sampling of these proteins revealed different trajectories with persisting high serum levels, or secondary peaks, in patients with unfavorable outcome or in patients developing secondary detrimental events. Finally, NF-L (n = 2) only increased in the few studies available, suggesting a serum availability of >10 days. To date, automated assays are available for S100B and NSE making them faster and more practical to use.

CONCLUSION

Serial sampling of brain-specific proteins in serum reveals different temporal trajectories that should be acknowledged. Proteins with shorter serum availability, like S100B, may be superior to proteins such as NF-L in detection of secondary harmful events when monitoring patients with TBI.

The role of magnesium sulfate in the intensive care unit

Magnesium (Mg) has been developed as a drug with various clinical uses. Mg is a key cation in physiological processes, and the homeostasis of this cation is crucial for the normal function of body organs. Magnesium sulfate (MgSO4) is a mineral pharmaceutical preparation of magnesium that is used as a neuroprotective agent. One rationale for the frequent use of MgSO4 in critical care is the high incidence of hypomagnesaemia in intensive care unit (ICU) patients. Correction of hypomagnesaemia along with the neuroprotective properties of MgSO4 has generated a wide application for MgSO4 in ICU.