Mepivacaine HCl Research Articles

Evaluating the effectiveness of various agents as interim preservative media for biopsy specimens: An experimental in vitro study

In the field of medicine, diagnosing diseases involves various steps, procedures, and protocols. Histopathological examination remains the gold standard for a definitive and accurate diagnosis. This process relies on an initial step of tissue fixation.Formaldehyde is a traditional fixative material and is typically used as 10% or 4% buffered solutions. However, significant health risks are associated with formaldehyde exposure.Our paper aimed to evaluate and compare variable media as a preservative agent. The study included eight groups as follows: (1) normal saline 0.9%; (2) local anesthesia with epinephrine (2% Lidocaine HCl/ 1:100,000 epi); (3) local anesthesia without epinephrine (3% Mepivacaine HCl/ plain); (4) distilled water; (5) Saliva collected from healthy male participants; (6) Milk (Almarai- full-fat fresh milk); (7) Propolis; and (8) l0% formalin. Three tissue samples from each group were fixed in 10% formalin for 24 h after being preserved for 6 h at ambient temperature in their respective media. All specimens were stained with Hematoxylin and Eosin.The following histological structures were assessed: (1) superficial 1/3 of the epithelium, (2) middle 1/3 of the epithelium, (3) lower 1/3 of the epithelium, (4) basement membrane/rete ridges, (5) fibrous connective tissue, (6) blood vessels/endothelial cells, (7) skeletal muscle, (8) adipose tissue, and (9) nerve bundles. A numerical rating system was employed to assess these components, with scores ranging from 1 to 4.Our findings suggest propolis has promising potential as a tissue fixative. This study highlighted the effectiveness of propolis as a preservative and fixative solution, which warrants further investigation.

Analysis of Hemodynamic Changes after Administration of Mepivacaine HCL 3% with Prilocaine 3% Solution + Felypressin

Introduction: With regards to the usage of local anesthetic drugs in hypertensive patients, this study is designed for comparing the effects of mepivacaine 3% and prilocaine 3% + felypressin in hemodynamic changes after inferior alveolar nerve block to help dental practitioner select anesthetic solutions for hypertensive patients considering their hemodynamic effects in order to provide patient safety.Materials & Methods: In this double blind clinical trial 32 patients were referred to oral and maxillofacial surgery department of Shiraz dentistry school in 2021 were divided into 2 groups with 16 patients in each group. In first group, inferior alveolar nerve block was accomplished by mepivacaine 3% and in the other group, prilocaine 3% and felypressin. Then systolic and diastolic blood pressure, heart rate and oxygen saturation were measured at 4 different time points consisting of before injection, immediately after injection, 10 minutes after injection and 30 minutes after tooth extraction. The data were analyzed by ANOVA and T-test (p value < 0.05).Results: There were no statistically significant differences in systolic blood pressure, diastolic blood pressure, heart rate and oxygen saturation changes between mepivacaine and prilocaine groups during all four sampling time points. But in each group, individually there were significant differences in systolic and diastolic blood pressure, heart rate and oxygen saturation in different times. In addition mepivacaine causes a significant increase in systolic blood pressure immediately after injection but in contrast prilocaine + felypressin didn’t do so.Conclusion: We recommend prilocaine + felypressin in comparison with mepivacaine for local anesthesia in hypertensive patients.

Different Spectrophotometric and Chromatographic Methods for Determination of Mepivacaine and Its Toxic Impurity.

Stability-indicating spectrophotometric, TLC-densitometric, and ultra-performance LC (UPLC) methods were developed for the determination of mepivacaine HCl (MEP) in the presence of its toxic impurity, 2,6-dimethylanaline (DMA). Different spectrophotometric methods were developed for the determination of MEP and DMA. In a dual-wavelength method combined with direct spectrophotometric measurement, the absorbance difference between 221.4 and 240 nm was used for MEP measurements, whereas the absorbance at 283 nm was used for measuring DMA in the binary mixture. In the second-derivative method, amplitudes at 272.2 and 232.6 nm were recorded and used for the determination of MEP and DMA, respectively. The developed TLC-densitometric method depended on chromatographic separation using silica gel 60 F254 TLC plates as a stationary phase and methanol-water-acetic acid (9 + 1 + 0.1, v/v/v) as a developing system, with UV scanning at 230 nm. The developed UPLC method depended on separation using a C18 column (250 × 4.6 mm id, 5 μm particle size) as a stationary phase and acetonitrile-water (40 + 60, v/v; pH 4 with phosphoric acid) as a mobile phase at a flow rate of 0.4 mL/min, with UV detection at 215 nm. The chromatographic run time was approximately 1 min. The proposed methods were validated with respect to International Conference on Harmonization guidelines regarding precision, accuracy, ruggedness, robustness, and specificity.

A Review of the Compatibility of Liposome Bupivacaine with Other Drug Products and Commonly Used Implant Materials

The compatibility of a medication with other drugs and implanted materials is an important factor impacting drug safety and efficacy. The liposomal formulation of the local anesthetic bupivacaine is designed to provide prolonged postsurgical analgesia. Its compatibility with other drugs and materials depends on the compatibility of the drug itself, along with the integrity of liposome and liposomal components. A series of studies was conducted to evaluate the compatibility of liposome bupivacaine with diluents, implanted materials, and other drugs likely to be encountered in the surgical settings in which it is used. Liposome bupivacaine demonstrated compatibility with diluents (normal saline, lactated Ringer's solution) and with implanted materials (silicone, stainless steel, titanium, polypropylene, expanded polytetrafluoroethylene), with little or no change in percent of free bupivacaine, packed particle volume, or particle size distribution; liposome bupivacaine exhibited little or no change in the properties of the test materials. Liposome bupivacaine had clinically meaningful interactions with other local anesthetics, including lidocaine, ropivacaine, mepivacaine, or bupivacaine HCl (at liposome bupivacaine to bupivacaine HCl ratios < 2:1), which resulted in substantial displacement and release of free bupivacaine from liposomes. Liposome bupivacaine may be locally administered after ≥ 20 minutes following local administration of lidocaine, ropivacaine, or mepivacaine. Co–administration of liposome bupivacaine and bupivacaine HCl into the same site should be at ratios ≥ 2:1. Interactions between liposome bupivacaine and epinephrine, corticosteroids, antibiotics, non–steroidal anti–inflammatory drugs, tranexamic acid, and opioid analgesics were not clinically meaningful; liposome bupivacaine may be safely co–administered with these agents. No adverse synergistic effects on liposome bupivacaine were observed in evaluations involving multiple medications compared with each drug's individual effects.

Transient Adverse Neurologic Effects of Spinal Pain Blocks

ObjectiveChronic neck or back pain can be managed with various procedures. Although these procedures are usually well-tolerated, a variety of side effects have been reported. In this study we reviewed cases of unexpected temporary adverse events after blocks and suggest possible causes.MethodsWe reviewed the records of patients treated with spinal pain blocks between December 2009 and January 2011. The types of blocks performed were medial branch blocks, interlaminar epidural blocks and transforaminal epidural blocks. During the first eight months of the study period (Group A), 2% mepivacaine HCL and triamcinolone was used, and during the last six months of the study period (Group B), mepivacaine was diluted to 1% with normal saline.ResultsThere were 704 procedures in 613 patients. Ten patients had 12 transient neurologic events. Nine patients were in Group A and one was in Group B. Transient complications occurred in four patients after cervical block and in eight patients after lumbar block. Side effects of lumbar spine blocks were associated with the concentration of mepivacaine (p<0.05). The likely causes were a high concentration of mepivacaine in five patients, inadvertent vascular injection in three patients, intrathecal leak of local anesthetics in one, and underlying conversion disorder in one.ConclusionSpinal pain blocks are a good option for relieving pain, but clinicians should always keep in mind the potential for development of inevitable complications. Careful history-taking, appropriate selection of the anesthetics, and using real-time fluoroscopy could help reduce the occurrence of adverse events.

Role of rumen fluid hypertonicity in the dehydration-induced hypophagia of cows

Three experiments were performed in non-lactating, rumen-fistulated cows to assess the role of rumen fluid hypertonicity in dehydration-induced hypophagia. First, the course of rumen fluid and plasma osmolality before and after an individual test meal was recorded when water was offered ad libitum and on the fifth day of a 65% water restriction period. Then, the effects of intraruminal water infusions on food intake were examined in dehydrated cows. Finally, two doses of the local anesthetic mepivacaine HCl were given into the rumen in an attempt to inactivate the osmosensors potentially involved in dehydration-induced hypophagia. Water restriction reduced test meal size and increased rumen fluid and plasma osmolality. Despite the smaller meal, the prandial increase in rumen fluid osmolality was more pronounced during water restriction than with water ad libitum. Independent of treatment, the test meal had no effect on plasma osmolality. Intraruminal water infusions during water deprivation decreased rumen fluid osmolality below the control level and normalized food intake. Injection of 2 or 4 g mepivacaine/cow into the rumen did not attenuate dehydration-induced hypophagia. All in all, these results suggest that rumen fluid hypertonicity, perhaps in concert with plasma hypertonicity, contributes to the early satiation induced by dehydration.

Effects of local anesthetics on rat leukocyte functions

To determine whether local anesthetics affect functions in macrophages, I examined the effects of 5 local anesthetics, lidocaine HCl, mepivacaine HCl, propitocaine HCl, procaine HCl, and tetracaine HCl, on chemotaxis and production of superoxide anion in rat peripheral macrophages. Rats were intraperitoneally injected with 1% glycogen. Peritoneal exudate cells containing macrophages were obtained from the peritoneal cavity 4 days after the administration. Chemotaxis was evaluated using a 48-well microchemotaxis chamber with a polycarbonate membrane filter. Production of superoxide anion was measured spectrophotometrically by a superoxide dismutase-sensitive reduction of ferricytochrome c. All of the local anesthetics examined at a dose of 1 mg ml inhibited (P < 0.05) chemotaxis and production of superoxide anion in macrophages. Moreover, pretreatment of macrophage suspensions with mepivacaine HCl, propitocaine HCl, procaine HCl, or tetracaine HCl at a dose of 1 mg ml resulted in inhibition of the production of superoxide anion. In contrast, pretreatment with lidocaine HCl at this concentration did not significantly affect the production of superoxide anion. These results suggest that all of the local anesthetics examined at a therapeutic concentration inhibit chemotaxis and production of superoxide anion in rat macrophages.

Partial molar volumes of some drugs in water and ethanol at 35 °C

Partial molar volumes, V0, of six drugs, mostly anaesthetics, viz., cinchocaine HCl, lidocaine HCl, mepivacaine HCl, procaine HCl, propranolol HCl, tetracaine HCl, in water and ethanol, calculated from precision densities obtained at 35 °C from a vibrating tube densitometer, are reported in this work. The data represent the smaller volumes of drug molecules in ethanol than in water. Volume contribution of hydrochloride part were calculated and excluded from V0 to assess the volume of free base component of the solutes. Volumes of free bases were also found smaller in ethanol, although much closer to those in water. The differences in volumes are interpreted as due to hydrophobicity of solutes. Relative hydrophobicities were estimated from volumes of transfer from aqueous to organic media. Correlation of V0 with van der Waal volumes are also reported. The hydrophobicity of these compounds is proposed to play a key role in the resulting drug action. Possible mechanism of drug binding with the membrane structure is also discussed.

Effects of local anesthetics on rat macrophage phagocytosis

We examined whether phagocytosis by macrophages (M phi s) is affected by local anesthetics (lidocaine HCl, prilocaine HCl, mepivacaine HCl, tetracaine HCl and procaine HCl). Opsonized zymosan, fetal bovine serum and one local anesthetic were added to each M phi sample. After a 30-min incubation, M phi s were washed to make Giemsa stained slides for counting. The phagocytosis rate was calculated by counting the phagocytosizing M phi s per 200 cells with an optical microscope, and rates for the samples containing local anesthetics were compared with those for the non-treated samples. Inhibition of phagocytosis was reversible, dose-dependent and pH dependent for all local anesthetics. Tetracaine HCl inhibited phagocytosis most and procaine HCl, least. These results suggest that local anesthetics at the level of clinical use inhibit leukocyte phagocytosis and therefore may interfere with the normal function of cells fundamental to host defense.

Continuous caudal epidural and subarachnoid anesthesia in mares: A comparative study: R.T. Skarda, Dr Med Vet, and W.W. Muir, DVM, PhD. Am J Vet Res 44:12, 2290–2298 (1983)

A new technique for producing continuous caudal epidural analgesia (CEA) and caudal subarachnoid analgesia (CSA) in adult horses (mares) without causing loss of pelvic limb function is described. A modified 17-gauge Huber-point directional needle was used to place a catheter with stylet into either the epidural or subarachnoid space at the lumbosacral intervertebral junction. The catheter was positioned at either the midsacral (S2-3) subarachnoid space or caudal portion of the sacral (S-3 to S-5) epidural space in 7 mares. The position of the catheter was confirmed radiographically. A 2% solution of mepivacaine HCl was used at an average dose of 0.061 +/- 0.013 mg/kg (1.3 +/- 0.3 ml) to produce CSA and 0.196 +/- 0.034 mg/kg (4.1 +/- 0.7 ml) to produce CEA. Onset of analgesia to superficial and deep muscular pinprick stimulation was faster with CSA than it was with CEA (8.2 +/- 2.4 minutes vs 21.4 +/- 3.8 minutes). Maximal caudal analgesia extended from spinal cord segments S-1 to coccyx during CSA and CEA. Periods of analgesia were shorter with CSA than with CEA (70.0 +/- 21.8 minutes vs 102.1 +/- 13.2 minutes). Perineal (S-4 to S-5) dermatome subcutaneous temperature was increased after epidural and subarachnoid injections of mepivacaine HCl solution. Heart rate, respiratory rate, systolic, diastolic, and mean arterial blood pressures, pulse pressure, rectal temperature, arterial blood gas tensions (PaCO2, PaO2), pHa, hematocrit, and total solid concentrations did not change significantly (P greater than 0.05) from base-line values after injection. The benefits and potential complications of CSA and CEA in horses are discussed.

Cardiopulmonary Arrest after Retrobular Block

A 61-year-old woman experienced a cardiopulmonary arrest immediately after the retrobulbar injection of a mixture of 2 ml of 0.5% bupivacaine HCl, 2% mepivacaine HCl, and hyaluronidase. The patient was immediately resuscitated but remained unconscious for a total of 20 minutes. All neurologic deficits resolved completely over the two hours following the cardiopulmonary arrest and no adverse sequelae were noted. We assumed that this cardiopulmonary arrest was precipitated by the local anesthetic being transported via retrograde flow through the ophthalmic artery and then by antegrade flow through the internal carotid artery to the thalamus and other midbrain structures.

Medial Rectus Muscle Palsy after Dental Anesthesia

A 42-year-old woman developed a transient partial third cranial nerve palsy after a supraperiosteal injection in the area of the middle superior alveolar nerve with mepivacaine HCl for dental anesthesia. This effect may have been caused by direct extension through a bony defect rather than by inadvertent intravascular injection of the anesthetic. Dentists and ophthalmologists should be aware of this phenomenon, which can result in permanent ocular palsy and even amaurosis.

Anaphylaxis due to local anesthesia hypersensitivity: report of case

During a routine dental appointment, a patient had an anaphylactic reaction to an injection of a local anesthetic, mepivacaine HCl 3% without a vasoconstrictor. Immediate medical treatment alleviated the symptoms and prevented a more profound collapse. The patient may have been sensitized during emergency treatment at a hospital at which time a local anesthetic was probably administered. Keeping life-saving drugs on hand will help in the immediate treatment of patients undergoing anaphylactic shock, but taking an accurate medical history will provide a clue to a patient's previous exposure and reaction to drugs, thereby preventing a medical emergency.

Systemic absorption of mepivacaine in commonly used regional block procedures.

Arterial plasma level-versus-time profiles of mepivacaine were determined for 70 surgical patients undergoing epidural, caudal, intercostalnerve, brachial-plexus, and sciatic/femoral-nerve blocks. A single dose of 500 mg of mepivacaine HCl was used. The conditions studied were route of injection, co

The pharmacology and toxicology of mepivacaine, a new local anesthetic

The local anesthetic activity, toxicity, and irritancy of mepivacaine HCl 1 (1-methyl-2′,6′-pipecoloxylidide hydrochloride) and a solution (solution B) containing 2.0% mepivacaine HCl and 1:20,000 levo-nordefrin (levo-2,4-dihydroxyphenyl-3-hydroxy-2-isopropylamine 2) have been studied by various methods. By the intracutaneous wheal test in guinea pigs mepivacaine HCl is 2.5 times more active than procaine HCl. The addition of levo-nordefrin produced a slight increase in the local anesthetic activity of the solution. Solution B was found as active as a solution of 2.0% lidocaine + epinephrine 1:100,000 by the same route of administration ( dilution test). At the 2.0% concentration level in solutions containing epinephrine 1:100,000 the duration of mepivacaine intradermal anesthesia was approximately 25% longer than that produced by lidocaine. Mepivacaine HCl was found to be as active as cocaine HCl by topical application to the rabbit eye. The topical TAC 5 was 0.18%. At 2, 3, 4, and 8% concentrations, mepivacaine HCl injected intraspinally in rabbits produced anesthesia lasting from 17 to 115 minutes (urethral anesthesia). The degree of intraspinal irritancy appears to be somewhat lower than that of lidocaine. By intravenous injection the following LD 50 values for mepivacaine HCl in mice, rabbits, and guinea pigs were obtained: 32±2, 22±2, and 20±1.4 mg/kg, respectively. Mepivacaine is approximately twice as toxic as procaine HCl and 40% less toxic than lidocaine HCl in mice. The subcutaneous LD 50 values were: 260±22, 110±11, and 94±10 mg/kg for mice, rabbits, and guinea pigs, respectively. Solution B and a 3% solution of mepivacaine HCl without levo-nordefrin (solution A) were well tolerated by monkeys and rats when injected intramuscularly or intravenously in single daily doses eighteen times in 21 days. No significant changes were observed in the body weights, blood counts, urinalyses, or blood pressures of the medicated animals at the end of the medication period. No changes attributable to medication with mepivacaine were observed at the autopsies of the medicated animals. By the trypan blue test the threshold irritant concentration 4 of mepivacaine HCl was 3.3%. That of lidocaine HCl, which was tested in parallel, was 1.9%. Lidocaine HCl is therefore approximately 70% more irritant than mepivacaine HCl. Applied topically on the rabbit eye, mepivacaine HCl and lidocaine HCl were well tolerated in concentrations up to 20%. Solution A and solution B produced a slight, transient inflammatory reaction when injected intramuscularly into rabbits in 1.0-cc doses. No lesions at the injection sites were observed at 7 days after the injection. In summary, mepivacaine HCl, which is 2.5 times more active than procaine HCl is only 25% more irritating and is well tolerated locally as well as systemically on repeated subcutaneous or intramuscular administration.