Management of pain using magnesium sulphate: A narrative review

Magnesium sulfate for postoperative pain in orthopedic surgery: A narrative review

Magnesium Sulfate (MgSO4) is a widely used adjuvant in anesthesia. Often administered with local anesthetics, it is known to reduce analgesic and opioid consumption while extending the duration of analgesia. MgSO4 applications extend to orthopedic surgeries, cardiovascular and urogenital procedures, offering extended postoperative pain relief. While commonly administered through various routes, there is a research gap concerning the comparative efficacy of intrathecal (IT) and intravenous (IV) MgSO4 administration. This narrative review aims to provide a comparison between IT and IV administration of MgSO4 particularly following orthopedic procedures, where pain management is paramount. A comprehensive literature search was conducted across several electronic databases, trial registries, and gray literature from inception to 2023. Inclusion criteria encompassed studies investigating the effects of perioperative IT administration of magnesium compared to perioperative IV administration of MgSO4 in patients undergoing surgery, with no language restrictions. Our search identified 4326 articles, of which 9 randomized controlled trials met our inclusion criteria. We summarized these selected articles. Four studies discussed IT magnesium sulfate (MgSO4) administration, 2 focused on IT administration in orthopedic surgeries, and 3 explored both IV and IT administration of MgSO4 in orthopedic surgery. IT MgSO4 shows promise in postoperative pain management, delaying block onset and extending duration. Personalized administration choice, considering patient factors and surgery type, is crucial. Further research is needed to refine strategies for better patient outcomes, particularly following orthopedic surgeries.

Ion Current Rectification Activity Induced by Boron Hydride Nanosheets to Enhance Magnesium Analgesia

The limited analgesic efficiency of magnesium restricts its application in pain management. Here, we report boron hydride (BH) with ion currents rectification activity that can enhance the analgesic efficiency of magnesium without the risks of drug tolerance or addiction. We synthesize MgB2, comprising hexagonal boron sheets alternating with Mg2+. In pathological environment, Mg2+ is exchanged by H+, forming two-dimensional borophene-analogue BH sheets. BH interacts with the charged cations via cation-pi interaction, leading to dynamic modulation of sodium and potassium ion currents around neurons. Additionally, released Mg2+ competes Ca2+ to inhibit its influx and neuronal excitation. In vitro cultured dorsal root neurons show a remarkable increase in threshold potential from the normal -35.9 mV to -5.9 mV after the addition of MgB2, indicating potent analgesic effect. In three typical pain models, including CFA-induced inflammatory pain, CINP- or CCI-induced neuropathic pain, MgB2 exhibits analgesic efficiency approximately 2.23, 3.20, and 2.0 times higher than clinical MgSO4, respectively, and even about 1.04, 1.66, and 1.95 times higher than morphine, respectively. The development of magnesium based intermetallic compounds holds promise in addressing the non-opioid medical need for pain relief.

Effects of a Modified Long-Acting Cocktail on Analgesia and Enhanced Recovery After Total Hip Arthroplasty: A Double-Blinded Randomized Clinical Trial

BACKGROUND

We compared the efficacy and safety of a modified cocktail for postoperative analgesia and early functional rehabilitation in patients undergoing total hip arthroplasty (THA).

METHODS

Magnesium sulfate and sodium bicarbonate were added to a cocktail of ropivacaine, epinephrine, and dexamethasone. Primary outcome measures were visual analog scale (VAS) pain scores at various intervals after surgery, morphine consumption for rescue analgesia after surgery, and time to first rescue analgesia. Secondary outcomes were hip function after surgery, daily walking distance, quadriceps muscle strength, and the incidence of postoperative adverse reactions.

RESULTS

Morphine consumption was significantly lower in the modified cocktail group than in the control group in the first 24 hours after surgery (6.2 ± 6.0 versus 14.2 ± 6.4 mg, P < .001), as was total morphine consumption (10.0 ± 8.6 versus 19.2 ± 10.1 mg, P < .001). The duration of the first rescue analgesia was significantly prolonged (23.7 ± 10.3 versus 11.9 ± 5.8 mg, P < .001). Morphine consumption was also reduced in the magnesium sulfate and sodium bicarbonate groups over a 24-hour period compared to the control group (P < .001). The modified cocktail group had significantly lower resting VAS pain scores than the control group within 24 hours after surgery (P < .050). The VAS pain scores during movement within 12 hours after surgery were also lower (P < .050). The experimental groups showed better hip range of motion (P < .050) and longer walking distance (P < .050) on the first postoperative day, and levels of inflammatory markers were significantly reduced. The incidence of postoperative adverse reactions was similar among the 4 groups.

CONCLUSIONS

The modified cocktail with a new adjuvant can prolong the duration of postoperative analgesia, reduce the dosage of rescue analgesics, and accelerate early postoperative functional recovery in patients undergoing THA.

Magnesium Sulfate and Its Versatility in Anesthesia: A Comprehensive Review

In the field of general anesthesia, magnesium sulfate (MgSO4) has become a valuable adjunct because it provides a range of benefits that enhance and optimize conventional aesthetic procedures. This review highlights the various intra-anesthetic benefits of MgSO4 while examining its complex function in the treatment using anesthesia. Magnesium inhibits the release of acetylcholine at the motor endplate and blocks calcium channels at presynaptic nerve terminals. This reduces the amplitude of endplate potential and the excitability of muscle fibers, which increases the potency of a neuromuscular blockade by nondepolarizing neuromuscular blockers. This activity may lessen the need for primary muscle relaxants. Moreover, its capacity to potentially reduce the total amount of main aesthetic agents needed emphasizes its function in maximizing anesthesia dosage, ensuring sufficient depth while perhaps potentially reducing adverse effects linked with increased dosages. MgSO4's adaptable qualities present a viable path for improving anesthetic outcomes, possibly improving patient safety and improving surgical results.

Postoperative Magnesium Sulfate Repletion Decreases Narcotic Use in Abdominal-Based Free Flap Breast Reconstruction

BACKGROUND

 Microsurgical breast reconstruction after mastectomy is now the standard of care for breast cancer patients. However, the costs and resources involved in free flap reconstruction can vary across different medical settings. To enhance patient outcomes in a cost-effective manner, we investigated the effect of intravenous magnesium sulfate (IV Mg) on postoperative opioid usage in this context.

METHODS

 A retrospective chart review was performed on all consecutive patients who underwent abdominal-based free flap breast reconstruction in a single institute following an enhanced recovery after surgery (ERAS) protocol. Patients who received IV Mg were compared with those who did not receive supplementation. Serum magnesium levels at different time points, narcotic consumption in units of oral morphine milligram equivalents (MMEs), and other postoperative recovery parameters were compared.

RESULTS

 Eighty-two patients were included. Those who received IV Mg on postoperative day 0 (n = 67) showed significantly lower serum magnesium levels before repletion (1.5 vs. 1.7 mg/dL, p = 0.004) and significantly higher levels on postoperative day 1 after repletion (2.2 vs. 1.7 mg/dL, p = 0.0002) compared to patients who received no magnesium repletion (n = 13). While both groups required a similar amount of narcotics on postoperative day 0 (20.2 vs. 13.2 MMEs, p = 0.2), those who received IV Mg needed significantly fewer narcotics for pain control on postoperative day 1 (12.2 MMEs for IV Mg vs. 19.8 MMEs for No Mg, p = 0.03). Recovery parameters, including maximal pain scores, postoperative mobilization, and length of hospital stay, did not significantly differ between the two groups.

CONCLUSION

 This is the first study to describe the potential analgesic benefits of routine postoperative magnesium repletion in abdominal-based free flap reconstruction. Further research is necessary to fully understand the role of perioperative magnesium supplementation as part of an ERAS protocol.

The Association Between Dietary Magnesium Intake and Pulmonary Function: Recent Fndings from NHANES 2007-2012

This article aims to study the correlation between dietary magnesium intake and pulmonary function, utilizing data from the National Health and Nutrition Examination Survey (NHANES) database. This cross-sectional study examined representative samples of adults from the USA (n = 818; NHANES 2007-2012) to explore the correlation between magnesium intake and pulmonary function. We obtained the average magnesium intake over 2 days, as well as measured pulmonary function parameters, including forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC, peak expiratory flow rate (PEF), and forced expiratory flow between 25 and 75% of FVC (FEF25-75%). Weighted multivariable linear regression was used to investigate the relationship between magnesium intake and pulmonary function. Additionally, subgroup analyses, interaction tests, and sensitivity analyses were conducted. Weighted multiple linear regression models revealed a significant positive correlation between magnesium and pulmonary function, even after adjusting for all included confounding variables. When we categorized magnesium intake into tertiles, we found that participants in the highest tertile of magnesium intake had significantly higher values for FVC (β: 898.54, 95%CI: 211.82-1585.25), FEV1 (β: 858.16, 95%CI: 212.41-1503.91), FEV1/FVC (β: 0.024, 95%CI: 0.004-0.044), PEF (β: 1324.52, 95%CI: 481.71-2167.33), and FEF25-75% (β: 831.39, 95%CI: 84.93-1577.84). Upon stratifying the data by age and sex, it was observed that this positive correlation was particularly pronounced among men aged 40-79. At the same time, the stability of the results was further confirmed by sensitivity analyses. This study suggested that dietary magnesium intake may improve pulmonary function.

Targeting the Endoplasmic Reticulum Stress-Linked PERK/GRP78/CHOP Pathway with Magnesium Sulfate Attenuates Chronic-Restraint-Stress-Induced Depression-like Neuropathology in Rats

Magnesium sulfate has demonstrated marked neuroprotection in eclampsia, hypoxia, stroke, and post-traumatic brain injury rodent models. However, its potential impact against chronic-restraint-stress (CRS)-induced depression-like neuropathology and associated alterations in endoplasmic reticulum (ER) stress have not been adequately examined. The present study aimed to investigate the neuroprotective potential of magnesium sulfate in a rat model of CRS-triggered depression-like behavioral disturbance and the underlying molecular mechanisms. Herein, CRS was induced by placing rats into restraining tubes for 6 h/day for 21 days and the animals were intraperitoneally injected with magnesium sulfate (100 mg/kg/day) during the study period. After stress cessation, the depression-like behavior was examined by the open-field test, sucrose preference test, and forced swimming test. The present data demonstrated that CRS triggered typical depression-like behavioral changes which were confirmed by the Z-normalization scores. Mechanistically, serum circulating corticosterone levels spiked, and the hippocampi of CRS-exposed animals demonstrated a significant decline in serotonin, norepinephrine, and dopamine neurotransmitters. At the molecular level, the hippocampal pro-inflammatory TNF-alpha and IL-1β cytokines and the oxidative stress marker 8-hydroxy-2'-deoxyguanosine (8-HG) increased in stressed animals. In tandem, enhancement of hippocampal ER stress was evidenced by the activation of iNOS/PERK/GRP78/CHOP axis seen by increased protein expression of iNOS, PERK, GRP78, and CHOP signal proteins in the hippocampi of stressed rats. Interestingly, magnesium sulfate administration attenuated the depression-like behavioral outcomes and the histopathological changes in the brain hippocampi. These favorable actions were driven by magnesium sulfate's counteraction of corticosterone spike, and hippocampal neurotransmitter decline, alongside the attenuation of neuroinflammation, pro-oxidation, and ER stress. In conclusion, the current results suggest the promising neuroprotective/antidepressant actions of magnesium sulfate in CRS by dampening inflammation, ER stress, and the associated PERK/GRP78/CHOP pathway.

Comparison of Perioperative Pregabalin and Duloxetine for Pain Management After Total Knee Arthroplasty: A Double-Blind Clinical Trial

Background

Chronic residual pain after total knee arthroplasty (TKA) is one of the challenges of postoperative pain management. Duloxetine, by controlling neuropathic pain, and pregabalin, by affecting nociceptors, can effectively manage postoperative pain.

Objectives

This study aimed to compare the effect of perioperative oral duloxetine and pregabalin in pain management after knee arthroplasty.

Methods

In this clinical trial, 60 patients scheduled for TKA under spinal anesthesia were randomly assigned to one of three groups A (pregabalin 75 mg), B (duloxetine 30 mg), and C (placebo). Drugs were administered 90 minutes before, 12, and 24 hours after surgery. The visual analog scale (VAS) score for pain, the first analgesic request time, postoperative analgesic consumption (i.v. paracetamol), and WOMAC score six months after surgery were recorded.

Results

The VAS score and analgesic consumption 48 hours after TKA in groups A and B significantly decreased compared to the placebo (P < 0.05). The first analgesic request time was longer in groups A and B than in group C (P < 0.05). While the differences were statistically significant, they are most likely not clinically significant. The WOMAC score before and six months after arthroplasty did not differ between the groups (P > 0.05).

Conclusions

Perioperative oral pregabalin and duloxetine similarly reduce pain and the need for analgesic consumption within 48 hours after TKA but do not affect knee mobility status.

Calcium-Dependent Interplay of Lithium and Tricyclic Antidepressants, Amitriptyline and Desipramine, on N-methyl-D-aspartate Receptors

The facilitated activity of N-methyl-D-aspartate receptors (NMDARs) in the central and peripheral nervous systems promotes neuropathic pain. Amitriptyline (ATL) and desipramine (DES) are tricyclic antidepressants (TCAs) whose anti-NMDAR properties contribute to their analgetic effects. At therapeutic concentrations <1 µM, these medicines inhibit NMDARs by enhancing their calcium-dependent desensitization (CDD). Li+, which suppresses the sodium−calcium exchanger (NCX) and enhances NMDAR CDD, also exhibits analgesia. Here, the effects of different [Li+]s on TCA inhibition of currents through native NMDARs in rat cortical neurons recorded by the patch-clamp technique were investigated. We demonstrated that the therapeutic [Li+]s of 0.5−1 mM cause an increase in ATL and DES IC50s of ~10 folds and ~4 folds, respectively, for the Ca2+-dependent NMDAR inhibition. The Ca2+-resistant component of NMDAR inhibition by TCAs, the open-channel block, was not affected by Li+. In agreement, clomipramine providing exclusively the NMDAR open-channel block is not sensitive to Li+. This Ca2+-dependent interplay between Li+, ATL, and DES could be determined by their competition for the same molecular target. Thus, submillimolar [Li+]s may weaken ATL and DES effects during combined therapy. The data suggest that Li+, ATL, and DES can enhance NMDAR CDD through NCX inhibition. This ability implies a drug−drug or ion−drug interaction when these medicines are used together therapeutically.

Non-opioid Intravenous Drugs for Pain Management in Patients Presenting with Acute Migraine Pain in the Emergency Department: A Comprehensive Literature Review

Context

Migraine is one of the most common causes of disability worldwide and the sixth cause of loss of life years due to disability. Migraine is reported mainly in young and middle-aged people, so it can cause a person to face many problems in doing daily tasks. The emergency department annually accepts 1.2 million patients with migraine. Therefore, timely diagnosis of the disease, knowledge of valuable drugs in an emergency, knowing how to use them, and finally, early treatment can play an essential and decisive role in improving patients' symptoms and reducing the disability caused by the disease. An essential and valuable drug category in the emergency department to manage pain is non-opioid intravenous (IV) drugs. Therefore, this study aimed to evaluate non-opioid IV drugs to manage pain in patients with acute migraines in the emergency department.

Method

This study conducted a comprehensive literature review to access the latest scientific studies and documents using keywords (acute migraine, non-opioid IV drugs, pain management) in reliable databases such as PubMed, Scopus, Web of Science, Cochrane, and Google Scholar. We reviewed 87 articles, 53 of which were evaluated and compared.

Results

A review study considers intravenous acetaminophen as a suitable option for the first-line treatment of acute migraine in the emergency department if the patient does not tolerate aspirin and non-steroidal anti-inflammatory drugs (NSAIDs). Various studies have obtained positive effects of NSAIDs and dihydroergotamine (DHE) in treating acute migraine. Prescribing anti-dopaminergic drugs can effectively reduce associated symptoms such as nausea and vomiting. Dexamethasone and magnesium sulfate are effective in preventing migraine and severe attacks. Intravenous sodium valproate is effective in moderate to severe migraine attacks or treatment-resistant migraines. In the emergency department, prescribing intravenous haloperidol, lidocaine, and propofol can help manage migraine and improve other associated symptoms, such as nausea or vomiting.

Conclusions

Non-opioid IV drugs are essential to manage pain and improve other migraine symptoms in the emergency setting. Knowing the above drugs and their optimal use has a decisive role in managing patients with acute migraine in the emergency department.

Interplay between exosomes and autophagy machinery in pain management: State of the art

Despite recent progress regarding inexpensive medical approaches, many individuals suffer from moderate to severe pain globally. The discovery and advent of exosomes, as biological nano-sized vesicles, has revolutionized current knowledge about underlying mechanisms associated with several pathological conditions. Indeed, these particles are touted as biological bio-shuttles with the potential to carry specific signaling biomolecules to cells in proximity and remote sites, maintaining cell-to-cell communication in a paracrine manner. A piece of evidence points to an intricate relationship between exosome biogenesis and autophagy signaling pathways at different molecular levels. A close collaboration of autophagic response with exosome release can affect the body's hemostasis and physiology of different cell types. This review is a preliminary attempt to highlight the possible interface of autophagy flux and exosome biogenesis on pain management with a special focus on neuropathic pain. It is thought that this review article will help us to understand the interplay of autophagic response and exosome biogenesis in the management of pain under pathological conditions. The application of therapies targeting autophagy pathway and exosome abscission can be an alternative strategy in the regulation of pain.

Current Strategies in Pain Regimens for Robotic Urologic Surgery: A Comprehensive Review

Context

Robotic surgery is becoming the most common approach in minimally invasive urologic procedures. Robotic surgery offers less pain to patients because of smaller keyhole incisions and less tissue retraction and stretching of fascia and muscular fibers. Tailored pain regimens have also evolved and allowed patients to feel minimal to no discomfort after robotic urologic surgery, allowing in parallel better surgical outcomes. This study aims to analyze the most current pain regimens in robotic urologic surgery and to evaluate the most current pain protocols and corresponding outcomes.

Evidence Acquisition

A literature review was performed of published manuscripts utilizing Pubmed and Google Scholar on pain protocols for patients undergoing robotic urologic surgery.

Results

Multimodal analgesia is gaining ground in robotic urologic surgery. Regional analgesia includes four major modalities: Neuroaxial analgesia, intercostal blocks, tranvsersus abdominis plane blocks, and paravertebral blocks. Each approach has a different injection site, region of analgesia coverage, and duration of coverage depending upon local anesthesia and/or adjuvant utilized with advantages and disadvantages that make each modality unique and efficacious.

Conclusions

Robotic urologic surgery has offered the advantage of smaller incisions, faster recovery, less postoperative opioid consumption, and better surgical outcomes. Neuraxial, intercostal, transversus abdominis plane, and quadratus lumborum blocks are the best and most adopted approaches which offer optimal outcomes to patients.

Infusion Therapy in the Treatment of Neuropathic Pain

PURPOSE OF REVIEW

Neuropathic pain is a prevalent and burdensome condition. While oral medical therapies are the first-line treatment for refractory neuropathic pain, in some cases, infusion therapy may be employed. This article is a systematic review of recent publications regarding epidemiologic, pathophysiologic, diagnostic, and therapeutic advancements in the treatment of neuropathic pain using intravenous infusion therapy. Special consideration will be given to relevant and practically used agents and available information on outcomes.

RECENT FINDINGS

Individuals with neuropathic pain from various etiologies (e.g. trigeminal neuralgia, post-herpetic neuralgia, diabetic neuropathy) often find short-term relief from infusion therapies. However, it is difficult to generalize the findings of these studies to form a standard treatment regimen. The purpose of this paper is to provide clinicians an up-to-date summary of recent literature regarding several infusion therapies in treating neuropathic pain.