Epinephrine

Question 1

What is the pharmacologic category/class of epinephrine?

Answer 1

• endogenous catecholamine
• direct acting alpha/beta agonist

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Question 2

What is the mechanism of action of epinephrine?

Answer 2

• Alpha-1 stimulation → arteriolar vasoconstriction
• Beta-1 stimulation → cardiac stimulation and increased inotropy, chronotropy
• Beta-2 stimulation → bronchodilation

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Question 3

What are the adult and pediatric doses of epinephrine for cardiac arrest?

Answer 3

• Adult: 1 mg IV q3-5 mins
• Peds: 0.01 mg/kg IV q3-5 mins

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Question 4

What are the adult and pediatric infusion ranges for epinephrine?

Answer 4

• Adult: 0.1-1 mcg/kg/min → 1-20 mcg/min
• Peds: 0.1-1 mcg/kg/min

Can be used for inotropic support, symptomatic bradycardia, shock

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Question 5

Bolus doses of epinephrine can be used intraoperatively for a variety of reasons (anaphylaxis, bradycardia/hypotension); what are the adult and pediatric doses for this?

Answer 5

• Adult: 5-10 mcg to start, up to 100 mcg
• Peds: 1-2 mcg

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 2
Dr. C
Dr. Reed}

Question 6

What is the onset of action for epinephrine?

Answer 6

• Immediate

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Question 7

What is the duration of action for epinephrine?

Answer 7

• 5-10 minutes

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Question 8

What organ(s) are responsible for epinephrine’s clearance (metabolism/elimination)?

Answer 8

• Metabolism: Monoamine oxidase (intraneuronal reuptake), Liver (P450)
• Elimination: Kidneys

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Question 9

With low doses of epinephrine, __________ receptor selectivity predominates, while ___________ receptor selectivity predominates at increasing doses (>10 mcg/min)

Answer 9

• beta
• alpha

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 2
Nagelhout (7th), p. 177
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