Anesthesia and analgesia
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Anesthesia and analgesia · Sep 1995
Bactericidal activity of skin disinfectants on methicillin-resistant Staphylococcus aureus.
We studied bactericidal activity of 10% povidone-iodine, 0.5% chlorhexidine gluconate, and 0.5% chlorhexidine in 80% ethanol on four strains of methicillin-resistant and two strains of methicillin-susceptible Staphylococcus aureus. The pathogen was exposed to each of the disinfectants for 15, 30, 60, 120, and 240 s at room temperature. The inocula from these suspensions were cultured 72 h at 37 degrees C after the antimicrobial activity of the disinfectants in the suspensions was inactivated by 1:1000 dilution with neutralizer. ⋯ The 15-, 30-, and 60-s exposure to 10% povidone-iodine reduced the mean colony count by 55.2%, 91.2%, and 96.7%, respectively, and the exposures to 0.5% chlorhexidine gluconate reduced the mean colony count by 37.2%, 77.1%, and 93.3%, respectively. The difference in colony count between disinfectants was significant at 15- and 30-s exposures (P < 0.01 and 0.05, respectively). The results suggest that bactericidal activity of 0.5% chlorhexidine in 80% ethanol is more potent and more rapid against methicillin-susceptible and methicillin-resistant strains of S. aureus.
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Anesthesia and analgesia · Sep 1995
Relationship of inspired anesthetic concentration to plasma concentration and urinary excretion of sevoflurane metabolites in rats.
In patients, plasma concentrations of sevoflurane metabolites may be independent of inspired sevoflurane concentration over a defined dose range. In contrast, studies using rabbits have found that plasma concentrations and urinary excretion of fluoride ion are dose-dependent up to 3% inspired sevoflurane. We measured sevoflurane metabolite concentrations in adult male Sprague-Dawley rats and related them to inspired sevoflurane concentrations. ⋯ Sevoflurane metabolism by precision-cut liver slices in vitro became dose-independent at more than 10-30 microM sevoflurane. No evidence of substrate inhibition was observed. These data provide evidence that sevoflurane metabolite concentrations are almost independent of inspired anesthetic concentration over at least part of the clinically used concentration range.
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Anesthesia and analgesia · Sep 1995
Comparative StudyIntrathecal administration of liposomal morphine in a mouse model.
The authors determined the duration of analgesia, toxicity, and neuraxial distribution of liposomal morphine after intrathecal administration in the mouse. Analgesic duration was determined using the tail-flick test after intrathecal injection of 12.5, 25, or 50 micrograms of plain or liposomal morphine (n = 6 mice/dose/formulation). Toxicity of the formulations was compared by estimating LD50. ⋯ For plain morphine, the drug was not confined to a specific neuraxial segment, and segmental levels declined rapidly. After liposomal morphine, the most morphine was concentrated and persisted in the low spinal cord segment at each time interval. These results show that a single dose of liposomal morphine produces prolonged analgesia with decreased toxicity compared to the plain formulation.