Magnocaine: Physical Compatibility and Chemical Stability of Magnesium Sulphate and Lidocaine Hydrochloride in Prefilled Syringes

Effectiveness of Lidocaine versus Lidocaine with Magnesium Sulphate During Inferior Alveolar Nerve Block in Patients with Symptomatic Irreversible Pulpitis: A Randomised Double-Blinded Clinical Trial

OBJECTIVE

This study aimed to compare the effectiveness of lidocaine with magnesium sulphate in patients undergoing root canal treatment following irreversible pulpitis.

METHODS

A total of 86 patients were randomised to receive 1.8 ml of 2% lidocaine replaced with 0.2 ml of 10% magnesium sulphate with 1: 80,000 epinephrine (n=43) as MGS group and 1.8 ml of 2% lidocaine with 1: 80,000 epinephrine (n=43) as LDC group. Preoperative visual analogue scale (VAS) pain scores were record-ed. Patients were instructed to report any perioperative pain felt during the access cavity preparation and when introducing the first patency file (#10 k) in the root canal and perioperative VAS recorded.

RESULTS

The success rate of the inferior alveolar nerve block (IANB) was higher in the MSG group. The mean+-SD of perioperative pain was 0.16+-0.37 in the MSG group and 3.13+-0.77 in the LDC group. The MGS group produced better anaesthetic efficacy with a p-value of 0.01.

CONCLUSION

Based on the results, adding 10% magnesium sulphate to 2% lidocaine increased the effective-ness of IANB in patients with symptomatic irreversible pulpitis of mandibular molar teeth.

Compatibility and stability of an admixture of multiple anaesthetic drugs for opioid-free anaesthesia

The ability to combine and use drugs in a single infusion device may be useful in resource-limited settings. This study examined the chemical stability of an opioid-sparing mixture of ketamine, lidocaine and magnesium sulphate when combined in a single syringe. High-performance liquid chromatography and atomic absorption spectrophotometry were performed on six syringes containing the three-drug mixture. Since most opioid-sparing techniques typically rely on a 24-hour infusion regime, we tested stability at the initial admixing and 24 hours later. Stability was defined as a measured drug concentration within 10% of expected, with the absence of precipitation or pH alterations. Pharmacokinetic simulations were conducted to further show that the achieved plasma drug concentrations were well within an effective analgesic range. All mixed drug concentration measurements were within the required 10% reference limit. No obvious precipitation or interaction occurred, and pH remained stable. Drug stability was maintained for 24 hours. Pharmacokinetic simulations showed that ketamine and lidocaine were within their minimum analgesic effect concentrations. Our results show that this three-drug mixture is chemically stable for up to 24 hours after mixing, with a pharmacokinetic simulation illustrating safe, clinically useful predicted plasma concentrations when using the described admixture.

Opioid-Free Anesthesia: Physico Chemical Stability Studies on Multi-Analyte Mixtures Intended for Use in Clinical Anesthesiology

Objectives: Opioid-free anesthesia is used increasingly often in hospitals around the world. In this type of anesthesia, opioids are replaced by other analgesics, such as ketamine, lidocaine, dexmedetomidine, and magnesium sulfate. Many clinicians prepare these agents as dual, triple, or quadruple admixtures within a single syringe. However, data on the stability of the individual substances within these preparations over time and in different storage conditions is very limited. Here, we aim to investigate various admixture of dexmedetomidine, ketamine, lidocaine, and magnesium sulfate with respect to the stability of the individual agents over time at different storage conditions. Methods: An ultra-high performance liquid chromatography method coupled to mass spectrometric detection was developed and validated to determine the stability of lidocaine, ketamine, and dexmedetomidine. Quantification of magnesium was carried out in parallel by potentiometric titration. Results: Our results demonstrate the stability of dual, triple or quadruple mixtures of selected substances in 0.9% saline under different storage conditions. Under all conditions, analyzed admixtures remain stable for at least 8 weeks. The quadruple mixture of lidocaine, ketamine, dexmedetomidine, and magnesium sulfate was storable for as long as 148 days without a significant loss of analyte. Conclusion: A new chromatographic method was successfully developed to analyze the stability of various pharmacological agents commonly used by clinicians in opioid-free anesthesia. The data we obtained indicate that mixing these agents together in a single syringe is safe and reliable and suggest that hospital pharmacies may prepare these solutions in advance of planned surgeries.

Post-operative analgesia of 2% lignocaine with or without magnesium sulfate for inferior alveolar nerve block in symptomatic mandibular molars - a randomized double blind controlled clinical trial

Background

Single inferior alveolar nerve block is ineffective in achieving adequate pulpal anesthesia in 30-80% of patients due to anatomical variations, local tissue pH, central sensitization, and several factors. Various supplementary techniques and combination of adjuvants with lignocaine are used to overcome these failures. Magnesium sulfate (MgSO₄), one such adjuvant, acts at the N-methyl-D-aspartate glutamate receptor resulting in effective anesthesia. The aim of this prospective, randomized, double-blind, clinical controlled trial was to evaluate the onset, anesthetic efficacy, duration and post-operative analgesia of 2% lignocaine with and without the addition of MgSO₄ in patients with symptomatic irreversible pulpitis and apical periodontitis.

Methods

Fourty-two patients were randomly divided into three groups: 2% lignocaine (group 1) and 2% lignocaine with MgSO₄ (75 mg) and (150 mg) in groups 2 and 3, respectively. Pre-operative vitals and Heft Parker-Visual Analogue Scale (HP-VAS) pain scores were recorded. The onset of anesthesia, anesthetic efficacy, and duration of anesthesia were evaluated post administration of the local anesthetic solution. The post-operative analgesia was examined at intervals of 2, 6, 12, 24, and 48 h.

Results

Administration of 150 mg MgSO₄ hastens the onset of anesthesia (1.29 min) and produces better anesthetic efficacy (3.29 HP-VAS) compared to group 2 (2.07 min and 9.14 HP-VAS) and group 1 (3.29 min and 35.79 HP-VAS), respectively. The duration of anesthesia was significantly higher in group 3 (247.07 min) compared to that of groups 2 and 1 (190 min and 110.21 min) with P < 0.05.

Conclusion

Combining 75 mg or 150 mg of MgSO₄ with lignocaine is more effective than 2% lignocaine and 75 mg of MgSO₄ is adequate for endodontic procedures.