Anesthesiology
-
Randomized Controlled Trial Clinical Trial
Plasma inorganic fluoride concentrations after sevoflurane anesthesia in children.
Sevoflurane is degraded in vivo in adults yielding plasma concentrations of inorganic fluoride [F-] that, in some patients, approach or exceed the 50- micron theoretical threshold for nephrotoxicity. To determine whether the plasma concentration of inorganic fluoride [F-] after 1-5 MAC x h sevoflurane approaches a similar concentration in children, the following study in 120 children scheduled for elective surgery was undertaken. ⋯ It was concluded that, during the 24 h after 2.7 +/- 1.6 MAC x h sevoflurane, the peak recorded [F-] is low (15.8 microns), F- is eliminated rapidly, and children are unlikely to be at risk of nephrotoxicity from high [F-].
-
Malignant hyperthermia (MH) is an important cause of anesthesia-induced death. Malignant hyperthermia susceptibility is diagnosed using the in vitro caffeine/halothane contracture test (CHCT) in fresh muscle biopsy specimens. The CHCT test is highly invasive, expensive, and lacks 100% specificity. Genetic and biochemical evidence provide strong support for the view that the substitution of cysteine for arginine 614 (Arg614Cys) in the human ryanodine receptor gene is one of several mutations that are likely to cause human MH. DNA testing was compared with CHCT as a means of predicting MH susceptibility in a large MH family in which the Arg614Cys mutation was detected. ⋯ An absolute correlation between DNA test results and CHCT assignment could not be made in this kindred. Possible explanations for discordance are that the Arg614Cys mutation is not linked to MH, that a second MH mutation is segregating in the family, or that there are errors in the CHCT. Because there is strong evidence supporting the causal nature of the Arg614Cys mutation, the discordant persons are not closely related within the pedigree as they would be if a second MH mutation were segregating, and the CHCT is not 100% accurate, we propose that the observed discordance between DNA test results and CHCT assignment in this kindred results from two false-positive diagnoses by the CHCT.
-
Pneumocephalus has been linked to several clinical conditions, including headache, lethargy, and even brain herniation or death. The effects of different normobaric oxygen concentrations and durations of therapy on the rate of air absorption were examined. ⋯ Based on mathematical model predictions, an FIO2 of 0.4 or 1.0 for at least 1 week or 2 days, respectively, will significantly decrease the time for absorption of a pneumocephalus.
-
Randomized Controlled Trial Clinical Trial
Residual block after mivacurium with or without edrophonium reversal in adults and children.
The rapid recovery from mivacurium- induced neuromuscular block has encouraged omission of its reversal. The purpose of this study was to determine, in children and in adults, whether failure to reverse mivacurium neuromuscular block was associated with residual neuromuscular block on arrival in the postanesthesia care unit. ⋯ This study demonstrated that, in adults, failure to reverse mivacurium neuromuscular block was associated with an increased incidence of residual block. Such weakness was not observed in children receiving similar anesthetic and neuromuscular blocking regimens.