The Experts below are selected from a list of 87 Experts worldwide ranked by ideXlab platform
Rachel H. Foster - One of the best experts on this subject based on the ideXlab platform.
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Rapacuronium bromide: a review of its use in anaesthetic practice.
Drugs, 1999Co-Authors: Susan V. Onrust, Rachel H. FosterAbstract:UNLABELLED Rapacuronium bromide (rapacuronium) is an aminosteroid, nondepolarising neuromuscular blocking agent (NMBA). At the recommended dose for endotracheal intubation (1.5 mg/kg), an intravenous bolus of rapacuronium has a rapid onset (approximately 1.2 to 1.8 minutes) and short duration of action (10.2 to 16.5 minutes) in adults undergoing elective surgery. Rapacuronium 1.5 mg/kg produced clinically acceptable intubating conditions in 68 to 89% of these patients at about 1 minute after administration. The onset, extent and duration of action and clinical efficacy of an intubating dose of rapacuronium appeared to be similar in the general adult population, adult patients with renal or hepatic dysfunction, patients undergoing Caesarean section, and elderly, paediatric or obese adult patients. Onset time with rapacuronium 1.3 to 2.5 mg/kg (0.9 to 1.8 minutes) was similar to or slower than that with a 1 mg/kg dose of the depolarising NMBA Suxamethonium Chloride (0.8 to 1.2 minutes). Intubating conditions were clinically acceptable about I minute after administration in 86 to 100% of patients with rapacuronium 1.3 to 2.5 mg/kg compared with in 88 to 97% of patients with Suxamethonium Chloride 1 or 1.5 mg/kg. Spontaneous recovery was slower with rapacuronium than with Suxamethonium Chloride, but neostigmine 0.04 or 0.05 mg/kg administered 2 or 5 minutes after rapacuronium 1.3 or 1.5 mg/kg accelerated recovery. In the few available comparative clinical trials, rapacuronium 1.5 mg/kg appeared to have a more rapid onset of action than the nondepolarising NMBAs mivacurium Chloride 0.25 mg/kg, rocuronium bromide 0.45 or 0.6 mg/kg or vecuronium bromide 0.07 mg/kg, and a shorter duration of action than rocuronium bromide 0.45 or 0.6 mg/kg or vecuronium bromide 0.07 mg/kg. Additional boluses (< or =3) of rapacuronium 0.5 or 0.55 mg/kg after an intubating bolus of 1.5 mg/kg provided continued skeletal muscle relaxation during short surgical procedures in adult patients. However, these patients may recover more slowly than those who receive a single bolus of the drug. Bronchospasm was the most common treatment-related adverse event with rapacuronium 0.3 to 3 mg/kg (3.4% of adult patients). Tachycardia, injection site reaction and hypotension were also reported in small proportions of patients (1.6, 1.1 and 0.9%). The overall incidence of drug-related adverse events was similar with rapacuronium 1.5 or 2.5 mg/kg or Suxamethonium Chloride 1 mg/kg (8 vs. 6%) but bronchospasm, tachycardia and injection site reaction tended to occur more often with rapacuronium. CONCLUSIONS At the recommended dose of 1.5 mg/kg, the nondepolarising NMBA rapacuronium has a rapid onset and short duration of action. It may provide a nondepolarising alternative to Suxamethonium Chloride for endotracheal intubation. Rapacuronium may be preferred over rocuronium bromide, vecuronium bromide or mivacurium Chloride in this indication.
Olakunle Oginni - One of the best experts on this subject based on the ideXlab platform.
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modified electroconvulsive therapy in a resource challenged setting comparison of two doses 0 5 mg kg and 1 mg kg of Suxamethonium Chloride
Saudi Journal of Anaesthesia, 2020Co-Authors: Olurotimi Idowu Aaron, A F Faponle, B O Bolaji, Samuel K Mosaku, Anthony Taiwo Adenekan, Olakunle OginniAbstract:Background: Suxamethonium has been shown to have a superior modification of the convulsion associated with ECT compared to other muscle relaxants. The dosage of Suxamethonium used in ECT varies widely based on the experiences of practitioners. The study aimed to determine and compare the effectiveness and side effect profile of 0.5 mg/kg and 1 mg/kg in modified ECT. Subjects and Methods: This was a prospective randomized crossover study, comparing the effects of Suxamethonium at a dose of 0.5 mg/kg, and 1.0 mg/kg in 27 patients who had a total of 54 sessions of modified ECT. The primary outcome parameters were quality of convulsion and onset and duration of apnoea. The secondary outcome parameters were hemodynamic variables, arterial oxygen saturation, delayed recovery, muscle pain, vomiting, headache, prolonged convulsion, and serum potassium. Data collected were entered into proforma and analyzed using Statistical Package for Social Sciences (SPSS) version 17.0. Parametric variables are presented as means and standard deviations while non-parametric variables are presented as frequencies and percentages. The level of significance (P-value) was considered at 0.05. Results: Sixteen patients (59%) had acceptable convulsion modification with 0.5 mg/kg Suxamethonium compared to 23 patients (85%) with the use of 1.0 mg/kg Suxamethonium (P = 0.016). There was no statistically significant difference in the duration of convulsion, the onset of apnoea, and the duration of apnoea with the two doses. Changes in heart rate, blood pressure, arterial oxygen saturation, and serum potassium level that accompany the mECT were comparable with the two doses of Suxamethonium studied. Conclusions: A better modification of convulsion with comparable hemodynamic and side effect profile is achieved during mECT with the use of 1.0 mg/kg Suxamethonium compared to 0.5 mg/kg.
Teri E Klein - One of the best experts on this subject based on the ideXlab platform.
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pharmgkb summary succinylcholine pathway pharmacokinetics pharmacodynamics
Pharmacogenetics and Genomics, 2015Co-Authors: Maria L Alvarellos, Ellen M Mcdonagh, Sephalie Patel, Howard L Mcleod, Russ B Altman, Teri E KleinAbstract:The application of surgical treatments is greatly enhanced by the availability of anesthetic agents, such as neuromuscular blockers. Succinylcholine Chloride (2,2′-[(1,4-dioxo-1, 4-butanediyl) bis (oxy)] bis [N, N, N-trimethylethanaminium] diChloride), also known as Suxamethonium Chloride, is a depolarizing neuromuscular blocking agent (NMBA) on the World Health Organization's List of Essential Medicines. Because of its rapid onset of action and short half-life, it is commonly used in medical procedures that require short-term skeletal muscle paralysis, including rapid intubation in emergency medical situations. The clinical application of succinylcholine (SCH) is tempered by the occurrence of rare, but dramatic adverse reactions and some were the earliest known examples of pharmacogenetics. In many cases, patients with functionally characterized single nucleotide polymorphisms (SNPs) in specific genes in either the pharmacokinetic (PK) or pharmacodynamic (PD) pathways of SCH are at increased risk of these adverse reactions. The ubiquity of SCH in medical procedures makes understanding the pharmacogenomics of SCH critical for identifying susceptible patients such that suitable interventions and alternatives may be utilized. Figure 1 illustrates the PD and PK pathways of SCH and a fully interactive version of these pathways can be accessed at PharmGKB (https://www.pharmgkb.org/pathway/PA166122732). Figure 1 Stylized cells depicting the metabolism and mechanism of action of succinylcholine. Note: the star symbol on the DHPR indicates that it has been activated by depolarization of the t-tubules. A fully interactive version is available at PharmGKB http://www.pharmgkb.org/pathway/PA166122732 ... Pharmacodynamics Structurally, SCH consists of two acetylcholine (ACh) molecules linked end to end by their acetyl groups [1, 2]. ACh is the endogenous agonist of the nicotinic acetylcholine receptor (nAChR), a ligand-gated, non-specific cation channel that is formed by five sub-units organized around a central pore. There are two α1 subunits, and one β1, δ, and e sub-units. Each sub-unit of the nACHR is encoded by one of four genes (α1 is encoded by CHRNA1, β1 is encoded by CHRNB1, δ is encoded by CHRND, and e is encoded by CHRNE) (Figure 1). The nAChR is located on the motor end plate of neuromuscular junction (NMJ) of the skeletal muscle membrane, also known as the sarcolemma. Binding of an agonist, such as ACh or SCH, promotes the open state of the channel. When the nAChR opens, sodium ions rush into the cell and potassium ions rush out resulting in membrane depolarization and generation of an action potential. In myocytes, depolarization stimulates muscle contraction [3-5]. L-type voltage gated calcium channels, also known as dihydropyridine receptors (DHPR), are located on invaginations of the sarcolemma called the transverse tubules (T-tubules). The DHPR is a complex of four sub-units (α1, α2δ, β, γ) and a distinct gene encodes each sub-unit. CACNA1S encodes the α1 sub-unit (also called Cav1.1), the primary sub-unit of the channel that contains the voltage sensor, gating apparatus and channel pore of DHPR [6]. The DHPR is mechanically coupled to the ryanodine receptor (RYR1), a homotetrameric voltage gated calcium channel that is located on the sarcoplasmic reticulum (SR) and encoded by the RYR1 gene [7] (Figure 1). When skeletal muscles are at rest, the troponin complex allosterically inhibits the formation of a cross-bridge between myosin and actin. When calcium is released into the myoplasm, it binds the troponin complex and allows myosin to bind to actin to initiate muscle contraction and continues for as long as ATP is freely available [8]. Upon depolarization of the sarcolemma, the DHPR undergoes a conformational change and transmits a signal to RYR1, which opens to release SR calcium stores into the myoplasm to initiate muscle contraction. Muscle relaxation occurs when calcium ATPases on the sarcoplasmic reticulum (SERCA) remove calcium from the myoplasm and pump it back into the SR [9]. Because it is a depolarizing NMBA, SCH first induces muscle fasiculations followed by flaccid muscle paralysis. SCH takes effect within 60 seconds of intravenous administration and paralysis lasts between 4-6 minutes during which time patients are monitored with an electric nerve stimulator [1]. Because of its short half-life SCH is indicated for medical procedures requiring short-term muscle paralysis, such as endotracheal intubation, neuromuscular surgery, and electroconvulsive therapy. Because SCH paralyzes the respiratory muscles, patients require mechanical ventilation and close monitoring for the duration of paralysis. It has no direct effect on smooth or cardiac muscle contraction. SCH is often administered in combination with other anesthetics, analgesics and narcotics because although it blocks muscle contraction it has no effect on pain perception [1, 2, 10].
Jiang, Wen Guo - One of the best experts on this subject based on the ideXlab platform.
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Possible effect of muscle-relaxant anaesthetics on invasion, adhesion and migration of breast cancer cells
International Institute of Anticancer Research, 2016Co-Authors: Jiang A., Zhao H., Cai J., Jiang, Wen GuoAbstract:BACKGROUND: Aggressive surgical removal of the primary tumour is the preferred treatment, but with tumour progression, some tumours cannot be completely removed surgically. Anaesthetics are administered to facilitate surgery. However, anaesthetics act as a potential factor in tumour recurrence or metastasis. MATERIALS AND METHODS: Normal breast cells and cancer breast cells were treated with different doses of muscle-relaxant anaesthetics. The effects on breast cancer cell invasion, adhesion and migration of these anaesthetics were then investigated using in vitro models. RESULTS: With increasing dose of rocuronium bromide and Suxamethonium Chloride CRS, the number of MCF-10A and MCF-7 cells, but not that of MDA-MB-231 cells, decreased. There was almost no difference in the number of cells when the three cell lines were treated with different doses of vecuronium bromide. The study also demonstrated that rocuronium bromide promoted the invasion, adhesion and growth of MDA-231 cells, while Suxamethonium Chloride CRS had no effect. Interestingly, vecuronium bromide did not affect the motility and invasion of breast cancer cells significantly. CONCLUSION: An understanding of the effect of anaesthetics and their impact on tumour metastasis is important, thus using an appropriate aesthetic strategy could improve long-term survival in some patients
Esra Aykac - One of the best experts on this subject based on the ideXlab platform.
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investigation of in vitro antibacterial activity of Suxamethonium Chloride and rocuronium bromide
2011Co-Authors: Unase Buyukkocak, Figen Koc, Julide Sedef Gocmen, Osman Cağlayan, Esra AykacAbstract:Aim: Some non-antibiotic drugs may provide prevention against bacterial activity in their routine use. The antibacterial effects of two muscle relaxants (Suxamethonium Chloride and rocuronium bromide) were tested on bacteria using disk diffusion method. In addition, whether muscle relaxants altered the antibacterial activity of antibiotics was investigated with agar dilution method. Methods: Dilutions of 6 bacteria (S. aureus, S. epidermidis, E. faecalis, S. pyogenes, P. aeruginosa and E. Coli) were prepared and inoculated onto the plates containing Mueller Hinton agar. Under sterile conditions disks of drugs (n=4) containing three different doses were prepared. Four disks of each doses of the drugs were placed onto each bacterium plate. The plates were incubated and the inhibition zones were measured. Mueller Hinton agar plates containing four different concentrations of muscle relaxants were prepared to investigate whether muscle relaxants made any differences in the efficiency of antibiotics. These plates were inoculated with the bacteria tested. Standard antibiogram disks were placed onto the plates. The measured inhibition zones were compared with the control (Mueller Hinton agar plates without drug). Results: The investigated drugs did not exhibit any antibacterial activity on the bacteria tested and did not change the effects of the antibiotics. Conclusion: Although no in vitro activity of Suxamethonium Chloride and rocuronium bromide on bacteria was not found, in vivo studies are needed to determine the interactions with antibiotics.
