Anesthesiology
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Spinal cord perfusion pressure may be reduced when sodium nitroprusside is used to control proximal aortic hypertension during thoracic aortic clamping. The effect of esmolol infusion on spinal cord perfusion pressure during thoracic aortic clamping is unknown. This study compares spinal cord perfusion pressure following control of proximal hypertension with either sodium nitroprusside or esmolol during thoracic aortic clamping. ⋯ Esmolol was associated with greater spinal cord perfusion pressure, but adverse hemodynamic effects, when compared with nitroprusside during thoracic aortic cross-clamping. When only surviving dogs (4 control, 5 esmolol, 6 nitroprusside) are considered, the incidence of neurologic deficit was greater in nitroprusside-treated dogs than in either control or esmolol-treated dogs. No difference in outcome was present when all dogs are considered.
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Randomized Controlled Trial Clinical Trial
Increases in hemodynamic variables and catecholamine levels after rapid increase in isoflurane concentration.
Ventilation of the lungs with isoflurane in nitrous oxide and oxygen has been shown to increase the plasma concentration of norepinephrine. Whether this increase is related to the tachycardia and increased arterial blood pressures, seen following a sudden increase in the concentration of isoflurane, was tested in humans. ⋯ A sudden increase in isoflurane concentration is associated with a transient but clinically significant increase in heart rate, arterial pressures, and norepinephrine concentration.