Atropine Sulfate

Question 1

Atropine Classification

Answer 1

Anticholinergic/Parasympatholytic

Question 2

Atropine Mechanism

Answer 2

Muscarinic AchR antagonist -> inhibits parasympathetic stimulation in SA and AV nodal cells -> prevents K+ efflux and hyperpolarization -> positive chronotropy; no inotropic effect

Question 3

Atropine Pharmacokinetics

Answer 3

Onset: Immediate
Peak Effects: 2-4m
Duration: 4h
Half Life: 2-3h

Question 4

Atropine Indications

Answer 4

• Symptomatic Bradycardia
• Premed for RSI with bradycardia <50bpm
• Organophosphate poisoning

Question 5

Atropine Contraindications

Answer 5

None in emergency setting

Question 6

Atropine Side Effects/Adverse Reactions

Answer 6

Blurred vision, dilated pupils, dry mouth, tachycardia, drowsiness, confusion

Question 7

Atropine Dose

Answer 7

Adult:
Bradycardia: 0.5mg slow IV IO q3-5min up to 3mg
RSI: 0.5-1mg IV IO
Organophosphate poisoning: 2-5mg IV IO IM q20-30min until signs/symptoms resolve
Pedi:
Bradycardia: 0.02mg/kg IV IO; min single dose = 0.1mg, max = 0.5mg
RSI: 0.02 mg/kg IV IO
Organophosphate poisoning: 0.05mg/kg IV IO IM q20-30min until signs/symptoms resolve

Question 8

Atropine Precautions

Answer 8

• Do not give less than 0.5mg(adult) and 0.1mg(pedi) - causes parodoxical effect
• May cause paradoxical slowing or may be ineffective if used for 2degree type 2/3degree heart block
• Caution with acute MI -> increase myocardial O2 demand

Question 9

Atropine Drug Interactions

Answer 9

Few in EMS