Anesthesia and analgesia
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Anesthesia and analgesia · Jun 1997
Randomized Controlled Trial Clinical TrialEvaluation of residual neuromuscular block using train-of-four and double burst stimulation at the index finger.
We examined the percentage of tactile detection of fade in response to train-of-four (TOF), double burst stimulation3,3 (DBS3,3), or DBS3,2 at the index finger compared with that at the thumb during continuous infusion of vecuronium. One hundred five adult patients were studied. At TOF ratios (T4/T1) of 0.41-0.70, fades in response to TOF were more frequently identified by tactile means at the index finger than at the thumb (58% vs 26%, P < 0.05). ⋯ The baseline displacement of the index finger was significantly less than that of the thumb (P < 0.05). In summary, the percentage of tactile detection of fade in response to neurostimulation at the index finger is higher than at the thumb, and the absence of fade in response to DBS3,3 at the index finger is a good indicator of adequate recovery from neuromuscular block. This is probably because of the smaller baseline displacement of the index finger.
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Anesthesia and analgesia · Jun 1997
Randomized Controlled Trial Comparative Study Clinical TrialPropofol sedation during awake craniotomy for seizures: electrocorticographic and epileptogenic effects.
This prospective study evaluated the effects of propofol sedation on the incidence of intraoperative seizures and the adequacy of electrocorticographic (ECoG) recordings during awake craniotomy performed for the management of refractory epilepsy. Thirty patients scheduled for temporal or frontal lobectomy for epilepsy under bupivacaine scalp block were randomized to receive patient-controlled propofol sedation (PCS) combined with a basal infusion of propofol (n = 15) or neurolept analgesia using an initial bolus dose of fentanyl (0.7 microg/kg) and droperidol (0.04 mg/kg) followed by a fentanyl infusion (n = 15). Propofol administration was suspended 15 min before ECoG recording in the PCS group. ⋯ Evidence of low spike activity on ECoG did not correlate with the type of sedation administered. Higher frequency background ECoG activity was noted among patients who received propofol, but this did not interfere with ECoG interpretation. The use of propofol sedation does not appear to interfere with ECoG during epilepsy surgery, provided administration is suspended at least 15 min before recording.
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Anesthesia and analgesia · Jun 1997
The effects of sevoflurane anesthesia on insulin secretion and glucose metabolism in pigs.
We investigated the effects of two different concentrations of sevoflurane, 0.4 minimum alveolar anesthetic concentration (MAC) and 1.0 MAC, on insulin secretion before, during, and after sevoflurane anesthesia using three successive intravenous glucose tolerance tests (IVGTT) in pigs with indwelling catheters. We also investigated changes in the levels of plasma glucose, catecholamines (epinephrine [E], norepinephrine [NE]), and cortisol (Cor). The pigs were grouped as awake, 0.4 MAC, or 1.0 MAC. ⋯ These decreases were quickly reversible (control levels were regained within 2 h of the end of anesthesia), were probably dose-related, appeared not to be mediated by E, NE, or Cor. In addition, the INS/GLU ratio 2.5-4 h after the end of anesthesia was significantly higher in the anesthetized groups than in the awake group. We conclude that sevoflurane anesthesia has a rapidly reversible inhibitory effect on basal and glucose-stimulated insulin secretion, as do other inhaled anesthetics, and might induce insulin resistance.
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Anesthesia and analgesia · Jun 1997
Clinical TrialDisplacement of the double-lumen endobronchial tube can be detected by bronchial cuff pressure change.
We measured the bronchial cuff pressure of left-sided double-lumen endobronchial tubes (DLTs) in 54 patients to confirm the effect of DLT displacement on cuff pressure. After positioning the cephalad surface of the bronchial cuff of the DLT 2.5 cm distal to the carina (23 patients in the first part of the study) or just below the carina (23 patients in the second part), the cuff was withdrawn in 0.5-cm steps during right-sided, one-lung ventilation. The bronchial cuff pressure was measured, and the capnogram and pressure-volume loop, displayed by a side-stream spirometer, was evaluated. ⋯ The bronchial cuff pressure decreased significantly by 28.4 cm H2O (P < 0.01) and 21.3 cm H2O (P < 0.01) in the first and second parts, respectively, before the pressure-volume loop or the capnogram changed. The bronchial cuff pressure in the third part showed no significant change. We conclude that bronchial cuff pressure monitoring was very helpful in detecting displacement of the DLT during right-sided, one-lung ventilation.
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Anesthesia and analgesia · Jun 1997
Comparative StudyThe effect of xenon on spinal dorsal horn neurons: a comparison with nitrous oxide.
We compared the effects of xenon (Xe) on the spinal cord dorsal horn neurons with those of nitrous oxide (N2O) in cats anesthetized with chrolarose and urethane. We assessed the potency of both anesthetics by the inhibition of wide dynamic range neuron responses evoked by cutaneous noxious (pinch) stimulation to a hindpaw. During 70% Xe inhalation, the responses of 7 of 11 neurons to pinch stimulation were suppressed. ⋯ After 20 min of Xe inhalation, the response to pinch was suppressed to 49.5% +/- 8.2% (mean +/- SE), while N2O, 70% in oxygen, suppressed it to 45.9% +/- 7.9%. The difference between N2O and Xe was not significant. We conclude that Xe and N2O suppress the spinal cord dorsal horn neurons to a similar degree.