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In contrast to SNP infusions, propofol infusions into the brachial artery of conscious persons caused no significant vascular responses, despite the presence of therapeutic plasma concentrations of propofol within the forearm. The effects of propofol anesthesia on FVR and FVC are similar to the effects of sympathetic denervation by stellate ganglion blockade. Thus the peripheral vascular actions of propofol appear to be due primarily to an inhibition of sympathetic vasoconstrictor nerve activity.

In conclusion, sevoflurane appears to be similar to isoflurane and desflurane with a few exceptions. Sevoflurane was not associated with increases in heart rate in adult patients and volunteers, whereas higher MACs of isoflurane and desflurane and rapid increases in the inspired concentrations of these two anesthetics have been associated with tachycardia. Increasing concentrations of sevoflurane progressively decrease blood pressure in a manner similar to the other volatile anesthetics, and in unstimulated volunteers this decrease may be slightly less than with isoflurane at a higher MAC. Sevoflurane appears similar to isoflurane in its effect on regional blood flows, including the hepatic, renal, and cerebral circulation. In animals, sevoflurane appears to be a slightly less potent coronary vasodilator than isoflurane, and in a dog model, sevoflurane has not been associated with coronary flow redistribution ("steal"). Sevoflurane decreases myocardial contractility in a manner similar to equianesthetic concentrations of isoflurane and desflurane, and does not potentiate epinephrine-induced cardiac arrhythmias. Sevoflurane reduces baroreflex function in a manner similar to other volatile anesthetics. In several multicenter studies where patients with CAD or patients at high risk for CAD were randomized to receive either sevoflurane or isoflurane for cardiac or noncardiac surgery, the incidence of myocardial ischemia, infarction, and cardiac outcomes did not differ between treatment groups. Thus, sevoflurane has not been associated with untoward cardiovascular changes in volunteers and patients undergoing elective surgery compared with other volatile anesthetics, and it appears to offer a more stable heart rate profile than either isoflurane or desflurane.

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