Anesthesia and analgesia
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Anesthesia and analgesia · Sep 2008
Lengthening of the trachea during neck extension: which part of the trachea is stretched?
We sought to determine the distances of the three segments of the airway from upper incisors to carina in intubated patients in three different neck positions. ⋯ From neck flexion to extension, the UI-CA distance increased by 1.99 cm. The major contribution to this lengthening was an increase of the VC-SN distance by 1.74 cm; UI-VC increased by 0.36 cm whereas SN-CA did not change significantly. Averaging the three neck positions, SN-CA represented 60% of the VC-CA distance. Our findings may explain why tracheal tubes fixed at the mouth ascend in the trachea with neck extension.
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Anesthesia and analgesia · Sep 2008
Randomized Controlled TrialTransdermal nicotine for analgesia after radical retropubic prostatectomy.
Previous animal and human studies suggested that nicotine might have an antinociceptive effect. We hypothesized that the preoperative application of a 7 mg nicotine patch would result in reduced postoperative analgesic requirements in patients undergoing radical retropubic prostatectomy (RRP) under general anesthesia. ⋯ The preoperative application of a 7 mg nicotine patch resulted in a significant reduction in opioid consumption in patients undergoing RRP under general anesthesia. Despite this reduction in opioid use, there was no reduction in pain scores or postoperative nausea and vomiting with the use of transdermal nicotine.
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Anesthesia and analgesia · Sep 2008
Randomized Controlled TrialThe effect of propofol concentration on dispersion of myocardial repolarization in children.
QT interval prolongation on the electrocardiogram (ECG) may be drug-induced and is traditionally associated with torsades des pointes. A better predictor of torsades des pointes is the time interval between the peak and the end of the T-wave (Tp-e). Older studies of propofol's effect on the corrected interval (QTc) are conflicting and confounded by polypharmacy. It was recently shown that target-controlled infusion of propofol at 3 microg/mL has no effect on QTc or Tp-e. This plasma concentration of propofol is at the extreme lower end of the range for surgical anesthesia. In this randomized, double-blind, clinical study, we investigated the dose-response relationship between propofol, QTc, and Tp-e in a range of doses clinically relevant for surgical anesthesia. ⋯ Propofol has no effect on myocardial repolarization in healthy children at clinically relevant doses. This suggests that propofol would be a rational choice for children with a preexisting repolarization abnormality.
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Anesthesia and analgesia · Sep 2008
Randomized Controlled TrialSomatosensory evoked potentials by median nerve stimulation in children during thiopental/sevoflurane anesthesia and the additive effects of ketoprofen and fentanyl.
Somatosensory evoked potentials (SEPs) are used to determine the spinal cord and brain function during surgical procedures. In general, SEPs are sensitive to volatile anesthetics, but little is known about the effects of anesthesia maintenance with sevoflurane on SEPs in children. Analgesics are often provided during anesthesia, and supplementary drugs may also affect the SEPs. In this prospective clinical trial of 27 healthy, 3- to 8-yr-old children, we evaluated the effects of sevoflurane anesthesia after IV induction with benzodiazepine and barbiturate on median nerve SEP. In addition, the effects of two analgesics (ketoprofen and fentanyl) on SEPs were evaluated. ⋯ In children, anesthesia maintenance with 2% sevoflurane prolongs median SEP latencies in a manner that is similar to those reported for other volatile anesthetics. However, SEP monitoring can be done with sevoflurane inhalation, but the dosage should be adjusted due to interindividual variability. Co-administration of ketoprofen, and fentanyl did not affect the SEP latencies, but post hoc analysis suggested that older children had a decrease in cortical amplitudes.