During the dexmedetomidine infusion, which phase is associated with bradycardia and hypotension?

During the dexmedetomidine infusion, which phase is associated with bradycardia and hypotension?

• A. Hypertension
• B. Tachycardia
• C. Hyperthermia
• D. Bradycardia with hypotension

Answer: (D)

Dexmedetomidine can produce a biphasic cardiovascular response. Initially, peripheral alpha-2 activation can cause vasoconstriction, leading to hypertension and reflex tachycardia. As the drug’s central effects predominate, there is reduced sympathetic outflow and increased vagal tone, resulting in bradycardia and hypotension. The phase associated with bradycardia and hypotension is the later, centrally mediated phase, which is why a description of bradycardia with hypotension best fits this stage. The other options describe the early phase (hypertension and tachycardia) or an effect not typical of this drug (hyperthermia).

Dexmedetomidine can produce a biphasic cardiovascular response. Initially, peripheral alpha-2 activation can cause vasoconstriction, leading to hypertension and reflex tachycardia. As the drug’s central effects predominate, there is reduced sympathetic outflow and increased vagal tone, resulting in bradycardia and hypotension. The phase associated with bradycardia and hypotension is the later, centrally mediated phase, which is why a description of bradycardia with hypotension best fits this stage. The other options describe the early phase (hypertension and tachycardia) or an effect not typical of this drug (hyperthermia).