Anesthesiology
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The authors hypothesized that patients with cerebrovascular abnormalities or metabolic disorders may experience abnormality in cerebral circulation more frequently than patients without these risks. The current study attempted to assess jugular venous bulb oxygen saturation (SjvO2) in patients with preexisting diabetes mellitus or stroke undergoing normothermic cardiopulmonary bypass. ⋯ A reduced SjvO2 value was observed more frequently in patients with preexisting diabetes mellitus or stroke during normothermic cardiopulmonary bypass. It is possible that cerebral circulation during normothermic bypass is altered in patients with risk factors for cerebrovascular disorder.
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Acoustic reflectometry can be used to create a "one-dimensional image" of a cavity, such as the airway and lung, with the image displayed as an area-length curve. This pilot study was undertaken to determine whether acoustic reflectometry could be used to distinguish between an endotracheal and an esophageal intubation. ⋯ In this pilot study, acoustic reflectometry within seconds, and without resort to capnography, was able to generate characteristic and distinctive area-length profiles for both endotracheal and esophageal intubation. Acoustic reflectometry may have a role in the emergency imaging of the airway, and in the immediate detection of esophageal intubations, particularly in cases of cardiopulmonary arrest in which the usual techniques for confirmation of breathing tube placement fail.
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FK506 binding protein is closely associated with the sarcoplasmic reticulum ryanodine receptor-channel and can modulate its function. The ryanodine receptor is stabilized by its association with FK506 binding protein. The immunosuppressant drugs FK506 (tacrolimus) and rapamycin can promote dissociation of FK506 binding protein from the ryanodine receptor 1 and by this mechanism increase sensitivity of ryanodine receptor 1 to agonists such as caffeine. Furthermore, it was shown recently that treatment of normal human skeletal muscle with FK506 and rapamycin increased halothane-induced contracture. The authors investigated the effect of the immunosuppressants FK506 and rapamycin on halothane-induced Ca2+ release in skeletal muscle sarcoplasmic reticulum vesicles. ⋯ Dissociation of FK506 binding protein from its binding site in skeletal muscle sarcoplasmic reticulum vesicles can modulate halothane-induced Ca2+ release through the ryanodine receptor. Data are discussed in relation to the role of the FK506 binding protein in modulating the effect of halothane on the ryanodine receptor and the development of malignant hyperthermia phenotype.
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Randomized Controlled Trial Comparative Study Clinical Trial
Changes in the auditory evoked potentials and the bispectral index following propofol or propofol and alfentanil.
Midlatency auditory evoked potentials (MLAEP) show graded changes with increasing doses of hypnotics but little change with opioids. The effect of their combination on the MLAEP was evaluated. Also, the bispectral index (BIS) was compared with the ability of MLAEP to correlate with sedation and predict loss of consciousness. ⋯ MLAEP changes, like the BIS, correlate well with increasing sedation produced by propofol, and these changes in the MLAEP are independent of the presence of an opioid. Among all the MLAEP parameters, Pa and Nb latencies are the best predictors of increasing sedation and loss of consciousness.