Atropine

Question 1

What is the mechanism of action of atropine?

Answer 1

Anticholinergic

• Competetive antagonism of acetylcholine at muscarinic receptors

_{Apex Unit 5: Pharmacology 2 - NMB Reversal Agents
Nagelhout (7th ed.), pp. 173-174}

Question 2

What is the recommended dose of atropine when given in combination with neuromuscular blockade reversal?

Answer 2

• ~7-15 mcg/kg
  OR typically
• 0.4-0.6 mg IV

Depends on which AchE inhibitor it is combined with

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 2
Nagelhout (7th ed.), p. 174 - Table 12.11}

Question 3

What is the rationale for the use of atropine when reversing neuromuscular blockade with AchE inhibitors?

Answer 3

It can prevent or minimize cholinergic side effects

• bradycardia
• bronchoconstriction
• N/V
• salivation

Think of parasympathetic nervous system

_{Nagelhout (7th ed.), pp. 173-174}

Question 4

When administering neuromuscular blockade reversal, which AchE inhibitor is atropine usually paired with, and why?

Answer 4

• Edrophonium
• Their onset times are more favorably matched

Atropine is still used with neostigmine, since edrophonium is old school

_{Nagelhout (7th ed.), pp. 173, 174 - Table 12.11}

Question 5

What is the onset of action of atropine?

Answer 5

• Rapid/immediate with maximum effect in 1-4 minutes

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 2
Nagelhout (7th ed.), p. 174 - Table 12.11
UpToDate - Atropine (systemic): Drug Information}