Anesthesiology
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Randomized Controlled Trial Clinical Trial
Epidural analgesia during labor and maternal fever.
In recent observational studies, epidural analgesia during labor at patient request has been associated with maternal fever. The authors report a secondary analysis of fever in women who were randomized to receive either epidural or patient-controlled intravenous analgesia during labor. ⋯ Epidural analgesia is associated with maternal fever. However, nulliparity and dysfunctional labor are also significant cofactors in the fever attributed to epidural analgesia.
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Randomized Controlled Trial Clinical Trial
The dynamic relationship between end-tidal sevoflurane and isoflurane concentrations and bispectral index and spectral edge frequency of the electroencephalogram.
Inhalational anesthetics produce dose-dependent effects on electroencephalogram-derived parameters, such as 95% spectral edge frequency (SEF) and bispectral index (BIS). The authors analyzed the relationship between end-tidal sevoflurane and isoflurane concentrations (FET) and BIS and SEF and determined the speed of onset and offset of effect (t1/2k(e0)). ⋯ The speed of onset and offset of anesthetic effect did not differ between isoflurane and sevoflurane; isoflurane was approximately twice as potent as sevoflurane. The greater values of t1/2k(e0) derived from the BIS data compared with those derived from the SEF data may be related to computational and physiologic delays.
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Randomized Controlled Trial Clinical Trial
Use of the cuffed oropharyngeal airway as an alternative to the laryngeal mask airway with positive-pressure ventilation.
The cuffed oropharyngeal airway is a modified Guedel-type oral airway with a cuff at its distal end. The objectives of this study were to compare the ability of the cuffed oropharyngeal airway and the laryngeal mask airway to provide positive-pressure ventilation during general anesthesia, and to assess their relative ease of use and ability to reduce total fresh gas flow rates. ⋯ Positive-pressure ventilation is possible with the laryngeal mask airway and cuffed oropharyngeal airway devices. Although the cuffed oropharyngeal airway can be inserted easily by inexperienced users with a high first-attempt success rate (> 90%), manipulations of the device may be required to maintain a patent airway. The laryngeal mask airway device allows positive-pressure ventilation at slightly greater peak inspiratory pressures.
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Randomized Controlled Trial Clinical Trial
Rapid saline infusion produces hyperchloremic acidosis in patients undergoing gynecologic surgery.
Changes in acid-base balance caused by infusion of a 0.9% saline solution during anesthesia and surgery are poorly characterized. Therefore, the authors evaluated these phenomena in a dose-response study. ⋯ Infusion of approximately 30 ml x kg(-1) x h(-1) saline during anesthesia and surgery inevitably leads to metabolic acidosis, which is not observed after administration of lactated Ringer's solution. The acidosis is associated with hyperchloremia.
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Comparative Study
Continuous cardiac output in septic shock by simulating a model of the aortic input impedance: a comparison with bolus injection thermodilution.
To compare continuous cardiac output obtained by simulation of an aortic input impedance model to bolus injection thermodilution (TDCO) in critically ill patients with septic shock. ⋯ In mechanically ventilated patients with septic shock, changes in bolus TDCO are reflected by calibrated MCO over a range of cardiac output values. A single calibration of the model appears sufficient to monitor continuous cardiac output over a 2-day period with a bias of -0.1 +/- 0.8 l/min.