Anesthesiology
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Randomized Controlled Trial Clinical Trial
Efficacy of oral clonidine premedication in children.
Clonidine, an alpha 2-adrenoceptor agonist, has been shown to be effective as a preanesthetic medication in adults. The current study was designed to investigate the efficacy of two doses of oral clonidine as a premedicant preceding oral atropine in children. ⋯ These data indicate that, even in pediatric surgery, the combination of 4 micrograms/kg and 0.03 mg/kg oral clonidine is an effective premedication. However, the safety and optimal dose of clonidine in this setting remain to be determined.
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Propofol has been used for the maintenance of anesthesia. The effects of propofol infusion on splanchnic hemodynamics and liver oxygen consumption, however, have not been reported. In the current investigation, the authors studied the effects of a continuous infusion of propofol on systemic and splanchnic hemodynamics using a new method to measure liver oxygen consumption in awake control and anesthetized rats. ⋯ The maintenance of anesthesia using an infusion of propofol resulted in an increase in liver oxygen consumption that was fully compensated for by an increase in oxygen delivery to the liver. Splanchnic hemodynamics and liver oxygenation are not adversely affected during maintenance of anesthesia with propofol in the normal rat.
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Randomized Controlled Trial Comparative Study Clinical Trial
Epidural versus intravenous fentanyl for reducing hormonal, metabolic, and physiologic responses after thoracotomy.
Previous attempts to prevent all the unwanted postoperative responses to major surgery with an epidural hydrophilic opioid, morphine, have not succeeded. The authors' hypothesis was that the lipophilic opioid fentanyl, infused epidurally close to the spinal-cord opioid receptors corresponding to the dermatome of the surgical incision, gives equal pain relief but attenuates postoperative hormonal and metabolic responses more effectively than does systemic fentanyl. ⋯ The authors' results indicate that some aspects of the hormonal response to surgery are blocked more completely with epidural than with intravenous fentanyl. Adequate pain relief with epidural fentanyl, with a smaller mean dose, led to a smaller increase of some hormonal, metabolic, and physiologic responses after thoracotomy than in association with the adequate pain relief provided by intravenous fentanyl.