Anesthesiology
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Randomized Controlled Trial
Pharmacokinetics and pharmacodynamics of midazolam and metabolites in nonventilated infants after craniofacial surgery.
Because information on the optimal dose of midazolam for sedation of nonventilated infants after major surgery is scant, a population pharmacokinetic and pharmacodynamic model is developed for this specific group. ⋯ In nonventilated infants after major surgery, midazolam clearance is two to five times higher than in ventilated children. From the model presented, the recommended initial dosage is a loading dose of 1 mg followed by a continuous infusion of 0.5 mg/h during the night for a COMFORT-Behavior of 12-14 in infants aged 1 yr. Large interindividual variability warrants individual titration of midazolam in these children.
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Mean body temperature (MBT) is the mass-weighted average temperature of body tissues. Core temperature is easy to measure, but direct measurement of peripheral tissue temperature is painful and risky and requires complex calculations. Alternatively MBT can be estimated from core and mean skin temperatures with a formula proposed by Burton in 1935: MBT = 0.64 x TCore + 0.36 x TSkin. This formula remains widely used, but has not been validated in the perioperative period and seems unlikely to remain accurate in dynamic perioperative conditions such as cardiopulmonary bypass. Therefore, the authors tested the hypothesis that MBT, as estimated with Burton's formula, poorly estimates measured MBT at a temperature range between 18 degrees and 36.5 degrees C. ⋯ The authors concluded that estimation of MBT from mean skin and core temperatures is generally accurate and precise.
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The volatile anesthetic isoflurane induces hypoxia inducible factor (HIF)-1-responsive genes heme oxygenase 1, inducible nitric oxide synthase, and vascular endothelial growth factor (VEGF) expression. Little is known about the extent to which induction of HIF-1alpha is affected by isoflurane. ⋯ Isoflurane can up-regulate HIF-1alpha and enhance HIF-1-responsive genes heme oxygenase 1, inducible nitric oxide synthase, and VEGF mRNA expression in Hep3B cells. The induction of HIF-1alpha by isoflurane does not involve protein degradation but depends on translation pathway.
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This study describes a nationwide survey that estimates the number and characteristics of anesthesia-related deaths for the year 1999. ⋯ In comparison with data from a previous nationwide study (1978-1982), the anesthesia-related mortality rate in France seems to be reduced 10-fold in 1999. Much remains to be done to improve compliance of physicians to standard practice and to improve the anesthetic system process.
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Malignant hyperthermia is a pharmacogenetic disorder affecting humans, dogs, pigs, and horses. In the majority of human cases and all cases in animals, malignant hyperthermia has been associated with missense mutations in the skeletal ryanodine receptor (RyR1). ⋯ Heterozygous R163C mice represent a valid model for studying the mechanisms that cause the human malignant hyperthermia syndrome.