Effect of Dexmedetomidine, a Selective and Potent ??2-Agonist, on Cerebral Blood Flow and Oxygen Consumption During Halothane Anesthesia in Dogs

Abstract

The effect of the alpha 2-agonist dexmedetomidine on the cerebral blood flow (CBF) and the metabolic rate for oxygen was studied by a sagittal sinus outflow technique in dogs during halothane anesthesia. Dexmedetomidine was given in a dose (10 micrograms/kg) reported to reduce the anesthetic requirement of halothane by 90%. During 0.9% halothane anesthesia dexmedetomidine caused a significant reduction in CBF without influencing the metabolic rate for oxygen. Reducing the halothane concentration to 0.1% caused no further change in CBF, but increased the metabolic rate for oxygen 19%. The cerebral vasoconstrictive effect, combined with the 90% reduction in MAC for halothane, indicates that dexmedetomidine might be a useful adjunct to inhalation anesthetics during neurosurgery in situations where an increase in CBF should be avoided.

Dexmedetomidine-induced cerebral hypoperfusion exacerbates ischemic brain injury in rats

“…Dexmedetomidine continues to gain popularity as a sedative agent; it is also used in patients with traumatic brain injury because of its benefi cial effects on intracranial pressure (ICP) and CBF [24][25][26][27]. Dexmedetomidine has the potential to decrease blood pressure (BP) in a dose-dependent manner due to its alpha-2 agonist activity on the sympathetic ganglia and the resulting sympatholytic effects [10,28].…”

Alpha‐2 and imidazoline receptor agonistsTheir pharmacology and therapeutic role

“…Clonidine at high doses can be anxiogenic owing to alpha-1 [69], but paradoxically it has been used to treat panic disorders. Dexmedetomidine decreases cerebral blood flow in dogs during anaesthesia with both halothane and isoflurane, without evidence of global ischaemia occurring [70,71]. It has little effect on intracranial pressure and in the animal models of brain ischaemia has been shown to be neuroprotective [72].…”

Dexmedetomidine Supported Office Based Genioplasty: A Pilot Study

“…An interesting finding regarding this drug's sedative effect is its resemblance with natural sleep [27]. A decrease in cerebral perfusion pressure with no effect on intracranial pressure has been reported [29,30]. Dexmedetomidine has also been reported to have advantage of less anterograde amnesia, which can be a good factor in considering it for office based dental procedures [21].…”