Anesthesia and analgesia
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Anesthesia and analgesia · Jul 2004
Comparative StudyGamma-aminobutyric acidA receptors do not mediate the immobility produced by isoflurane.
Many inhaled anesthetics enhance the effect of the inhibitory neurotransmitter gamma aminobutyric acid (GABA), supporting the view that the GABAA receptor could mediate the capacity of inhaled anesthetics to produce immobility in the face of noxious stimulation (i.e., MAC, the minimum alveolar concentration required to suppress movement in response to a noxious stimulus in 50% of subjects). However, only limited in vivo data support the relevance of the GABAA receptor to MAC. In the present study we used two findings to test for the relevance of this receptor to immobilization for isoflurane: 1) differences among anesthetics in their capacity to enhance the response of receptor expression systems to GABA: isoflurane (considerable enhancement), xenon (minimal enhancement), and cyclopropane (minimal enhancement); and 2) studies showing that the spinal cord mediates MAC for isoflurane. ⋯ This indicates that GABA release in the spinal cord influences anesthetic requirement. However, the increase did not consistently differ among anesthetics and did not correlate with in vitro enhancement of GABAA receptors by these anesthetics. This supports the view that GABAA receptors do not mediate immobilization for isoflurane.
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Anesthesia and analgesia · Jul 2004
Case ReportsAn unusual cause of left ventricular outflow tract obstruction after mitral valve repair.
Left ventricular outflow tract (LVOT) obstruction caused by systolic anterior motion is a cause of failed mitral valve repair. Intraoperative transesophageal echocardiography has been very helpful in diagnosing problems with mitral valve repairs intraoperatively, allowing immediate correction. We report an unusual cause of LVOT obstruction attributed to prolapse of the annuloplasty ring into the LVOT. Intraoperative hemodynamics were normal, and the diagnosis would not have been made before leaving the operative suite without the transesophageal echocardiography.
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Anesthesia and analgesia · Jul 2004
Letter Randomized Controlled Trial Comparative Study Clinical TrialUse of small-dose bupivacaine (3 mg vs 4 mg) for unilateral spinal anesthesia in the outpatient setting.
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Life-threatening anaphylaxis or febrile nonhemolytic transfusion reactions after transfusion of platelet concentrates (PCs) is a serious clinical problem caused by the sensitizing of recipients to plasma components, such as immunoglobulin A, or by cytokines. There is a possible indication for washing of PCs in these thrombocytopenic patients. However, only platelets that show activation after physiological stimulation are useful. ⋯ Because of increased spontaneous activation after washing we could demonstrate cytometrically a loss of induced activation of washed platelets. Furthermore, washing resulted in an impaired ADP-induced aggregability of platelets. These results have led us to reduce the frequency of washing of PCs in our institution, where the only current indication for washing of PCs is in patients with a history of severe nonhemolytic transfusion reactions.
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Anesthesia and analgesia · Jul 2004
Case ReportsMucositis and airway obstruction in a pediatric patient.
Pediatric patients undergoing induction regimens of chemotherapy may require intubation and mechanical ventilation either for respiratory failure or airway compromise as a complication of their therapy. We describe a case of difficult airway management resulting from pseudomembrane formation in a 16-yr-old girl. The patient was undergoing induction chemotherapy for stage IV rhabdomyosarcoma and developed severe mucositis that led to progressive airway obstruction.