Anesthesiology
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Randomized Controlled Trial Comparative Study Clinical Trial
Desflurane reduces the febrile response to administration of interleukin-2.
Intraoperative fever is relatively rare considering how often pyrogenic causes are likely to be present and how common fever is postoperatively. This low incidence suggests that general anesthesia per se inhibits the normal response to pyrogenic stimulation. The authors therefore tested the hypothesis that desflurane-induced anesthesia produces a dose-dependent inhibition of the febrile response. ⋯ Desflurane-induced anesthesia produced a dose-dependent decrease in integrated and peak core temperatures after administration of pyrogen, with 1.0 MAC essentially obliterating fever. Anesthetic-induced inhibition of the pyrogenic response is therefore one reason that fever is an inconsistent clinical response to inflammation during surgery.
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Randomized Controlled Trial Comparative Study Clinical Trial
The influence of method of administration and covariates on the pharmacokinetics of propofol in adult volunteers.
Unresolved issues with propofol include whether the pharmacokinetics are linear with dose, are influenced by method of administration (bolus vs. infusion), or are influenced by age. Recently, a new formulation of propofol emulsion, containing disodium edetate (EDTA), was introduced in the United States. Addition of EDTA was found by the manufacturer to significantly reduce bacterial growth. This study investigated the influences of method of administration, infusion rate, patient covariates, and EDTA on the pharmacokinetics of propofol. ⋯ These results demonstrate that method of administration (bolus vs. infusion), but not EDTA, influences the pharmacokinetics of propofol. Within the clinically relevant range, the kinetics of propofol during infusions are linear regarding infusion rate.
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Randomized Controlled Trial Comparative Study Clinical Trial
Metabolic changes during recovery in normothermic versus hypothermic patients undergoing surgery and receiving general anesthesia and epidural local anesthetic agents.
Mild hypothermia is accompanied by metabolic changes. Epidural local anesthetic agents attenuate the surgical stress response, but it is not known whether they modulate thermal stress. ⋯ The postoperative metabolic changes obtained with epidural block were similar except for an attenuated concentration of epinephrine in normothermic patients compared with those who were mildly hypothermic.
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Randomized Controlled Trial Comparative Study Clinical Trial
Pulsed Doppler ultrasonography guidance for catheterization of the subclavian vein: a randomized study.
Catheterization of the subclavian vein may lead to severe complications. The current randomized study compared a technique of pulsed Doppler ultrasonography guidance and the standard method for subclavian vein catheterization. ⋯ Doppler guidance reduces the incidence of inappropriately positioned subclavian catheters.
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Randomized Controlled Trial Comparative Study Clinical Trial
Desflurane-mediated sympathetic activation occurs in humans despite preventing hypotension and baroreceptor unloading.
Increasing concentrations of desflurane result in progressive decreases in blood pressure (BP) and, unlike other currently marketed, potent volatile anesthetics, heightened sympathetic nervous system activity. This study aimed to determine whether baroreflex mechanisms are involved in desflurane-mediated sympathetic excitation. ⋯ The increase in basal levels of SNA with increasing concentrations of desflurane persisted despite "fixing" BP and thus is probably not due to hypotension and unloading of the baroreceptors. Further, the preservation of reflex increases in SNA to nitroprusside during desflurane indicates that desflurane preserves one component of the baroreflex in humans when BP is "fixed."