Pharmacodynamics of mivacurium chloride in 13- to 18-yr-old adolescents with thermal injury.

Background: Burned patients demonstrate resistance to the effects of non-depolarizing blocking drugs as a result of acetylcholine receptor changes. They also have decreased activity of plasma cholinesterase (PCHE), which metabolizes mivacurium. We hypothesized that decreased PCHE activity would decrease metabolism of mivacurium, and counteract the receptor-related resistance following burns.

Intramuscular rapacuronium in infants and children: a comparative multicenter study to confirm the efficacy and safety of the age-related tracheal intubating doses of intramuscular rapacuronium (ORG 9487) in two groups of pediatric subjects.

Background: This multicenter, assessor, blinded, randomized study was conducted to confirm and extend a pilot study in which intramuscular rapacuronium was given to infants and children to confirm efficacy and to evaluate tracheal intubating conditions.

Methods: Ninety-six pediatric patients were studied in two groups: infants aged 1 to 12 months (n = 46) and children aged 1 to 3 yr (n = 50). Infants received 2.

Neuromuscular effects of mivacurium in 2- to 12-yr-old children with burn injury.

Background: Burned patients are usually resistant to the neuromuscular effects of nondepolarizing relaxants, mostly because of receptor changes. The magnitude of the resistance is related to burn size and time after burn. Mivacurium is a muscle relaxant, degraded by plasma cholinesterase, whose enzyme activity is decreased in burns.

Intramuscular rocuronium in infants and children: a multicenter study to evaluate tracheal intubating conditions, onset, and duration of action.

Background: This multicenter, assessor-blinded, randomized study was done to confirm and extend a pilot study showing that intramuscular rocuronium can provide adequate tracheal intubating conditions in infants (2.5 min) and children (3 min) during halothane anesthesia.

Methods: Thirty-eight infants (age range, 3-12 months) and 38 children (age range, 1 to 5 yr) classified as American Society of Anesthesiologists physical status 1 and 2 were evaluated at four investigational sites.

Prolonged mivacurium infusion in young and elderly adults.

Purpose: This study was designed to evaluate pharmacodynamically and pharmacokinetically if the cis-cis isomer of mivacurium contributed to neuromuscular block during prolonged infusions lasting more than four hours in young adult and elderly (> 60 yr) patients.

Methods: The mechanomyogramic neuromuscular response of the adductor pollicis was recorded in 32 adults 18-59 yr. and 19 elderly (> 60 yr.

Potentiation of mivacurium by rocuronium is age- and time-dependent: a study in children, adolescents, and young and elderly adults.

Potentiation occurs when the steroidal muscle relaxant, rocuronium, is coadministered with the benzylisoquinolinium relaxant, mivacurium. The effect of time and age on this interaction was evaluated in four predetermined groups: children, adolescents, young adults, and elderly adults (15 per group) by monitoring the ulnar nerve-evoked force of contraction of the adductor pollicis (twitch response). During recovery from paralysis induced by 800 micrograms/kg of rocuronium, an infusion of mivacurium was started and maintained for at least 90 minutes to retain the twitch response at 1% to 9% of baseline tension (95 +/- 4% paralysis).

Mivacurium in infants and children.

Mivacurium is the only available short-acting nondepolarizing muscle relaxant in clinical use. It is a bis-quaternary benzylisoquinolinium ester hydrolysed by plasma-cholinesterase into inactive compounds. The ED and ED in children are about 50 μg·kg and 90 μg·kg respectively.

Mivacurium in infants and children.

Mivacurium is the only available short-acting nondepolarizing muscle relaxant in clinical use. It is a bis-quaternary benzylisoquinolinium ester hydrolysed by plasma-cholinesterase into inactive compounds. The ED50 and ED95 in children are about 50 micrograms.

Efficacy and safety of divided dose administration of mivacurium for a 90-second tracheal intubation.

Study Objective: To compare the safety and effectiveness of 0.25 mg divided doses of mivacurium chloride to succinylcholine for a 90-second tracheal intubation.

Design: Randomized, double-blind, multicenter study in two groups.

The human lumbar endplate. Evidence of changes in biosynthesis and denaturation of the extracellular matrix with growth, maturation, aging, and degeneration.

Study Design: The authors measured concentrations of specific molecules reflecting matrix synthesis and degradation in 121 human endplates and correlated them with aging and grade of degeneration.

Objectives: Abnormal endplate development has been implicated in many spinal abnormalities, yet little is known about endplate matrix component turnover.

Summary Of Background Data: Techniques are available to perform an in situ investigation of matrix component turnover with aging and degeneration.

Pseudocholinesterase-mediated hydrolysis is superior to neostigmine for reversal of mivacurium-induced paralysis in vitro.

Background: The metabolic hydrolysis of mivacurium (and succinylcholine) is markedly impaired in the presence of hereditary or acquired defects of pseudocholinesterase. Clinical reports are conflicting as to the utility of anticholinesterases, in the reversal of mivacurium paralysis. In the current study, the role of exogenous cholinesterases and/or of anticholinesterase, neostigmine, in the reversal of deep mivacurium-induced paralysis, was studied.

Comparison of neuromuscular, cardiovascular, and histamine-releasing properties of doxacurium and pipecuronium.

Study Objectives: To determine the neuromuscular, cardiovascular, and histamine releasing properties of doxacurium and pipecuronium at three times effective ED95 doses (3XFD95).

Design: Prospective, randomized clinical trial of adult patients.

Setting: University teaching hospital.

The influence of the age of the rat on the neuromuscular response to mivacurium in vitro.

The effective concentrations of mivacurium induced neuromuscular block were studied in the phrenic nerve-hemidiaphragm preparations of forty male Sprague-Dawley rats in four groups according to body weight, 10 g, 25 g, 100 g, and 200 g. Mivacurium was added to the Krebs' solution to obtain an initial concentration of 0.275 microgram.

The use of the laryngeal mask airway in children with bronchopulmonary dysplasia.

Airway maintenance with the laryngeal mask airway (LMA) was evaluated and compared to the endotracheal (ET) tube in 27 former premature infants and children with bronchopulmonary dysplasia (BPD) during second stage open-sky vitrectomy. The children were randomly assigned to a study group and anesthetized with halothane in N2O:O2. The airway was maintained with the LMA (n = 13) or the ET tube (n = 14).

Mivacurium infusion requirements following vecuronium: different response between adults and children.

The mivacurium infusion requirements following vecuronium were evaluated in 15 adults and 15 children in an open prospective clinical study. This study was undertaken to elucidate whether potentiation of effect occurred when a mivacurium infusion was administered after vecuronium was used for the facilitation of tracheal intubation. The adult patients were anaesthetized with N2O:02, propofol and fentanyl, the children with halothane (1%) N2O:O2.

Evaluation of different induction techniques for tracheal intubation.

Conditions for tracheal intubation and the hemodynamic changes associated with different intravenous anesthetic induction techniques were studied in seventy-two ASA I patients randomly assigned to one of six groups (G). Anesthesia was induced with I.V.