Atropine

Question 1

Atropine Class

Answer 1

• Parasympatholytic

* Anticholinergic Agent

Question 2

Atropine Action

Answer 2

• Atropine is a competitive inhibitor of acetylcholine @ muscarinic receptor sites.
• The increase of sympathetic activity due to the drug’s parasympatholytic effects.
• In the setting of symptomatic bradycardias, atropine decreases vagal effects on the heart resulting in increased chronotropy and dromotropy(with little or no inotropic effects).
• It is used in cholinergic exposures as a direct antidote for the poison.

Question 3

Atropine Indications

Answer 3

• Symptomatic Bradycardias
• Pre-intubation in children < one month of age
• Poisoning with: Organophosphates, Carbamates, and Mushrooms

Question 4

Atropine Contraindications

Answer 4

In cardiac arrest there are no contraindications. 
Non-arrest contraindications:
• Myasthenia gravis
• Closed-angle glaucoma
• Atrial fibrillation and flutter
• Known hypersensitivity
• Thyrotoxicosis
• Urinary tract obstruction

Question 5

Atropine Precautions

Answer 5

• Atropine may worsen 2nd degree Type II and 3rd degree AV blocks. Atropine may be relatively contraindicated and transcutaneous pacing preferred.
• Cardiovascular disease including: CAD and CHF
• COPD
• HTN
• Renal/hepatic disease
• Geriatrics
• Pregnancy I
• Minimum Doses >0.5 mg in adults >0.1 mg in children. Smaller doses can cause a paradoxical bradycardia.

Question 6

Atropine Dosage

Answer 6

Adults:
• Symptomatic Bradycardia: IV: 0.5-1 mg q 3-5 min.
Max dose: 0.04 mg/kg (full vagal blockade).
• Poisonings: IV/IM/ETT/IO: 1-2 mg PRN to decrease
cholinergic symptoms.
AUTOINJECTOR (MARK 1 KIT): 2 mg
Pediatrics:
• Symptomatic Bradycardia: IV/IO: 0.02 mg/kg q 3-5 min
Child: Minimum—0.1 mg Maximum—0.5 mg
Adolescent: Minimum—0.1 mg Maximum—1 mg
CETT: 2-3 times the IV dose diluted in 3-5 ml NS
• Poisonings: IV/IM: 0.05 mg/kg IV q 3-5 min PRN to
decrease cholinergic symptoms.
• Pediatric Pre-Intubation: IV/IO: 0.02 mg/kg

Question 7

Atropine Onset/ Duration

Answer 7

• Onset: Rapid

* Duration: 2-6 hours

Question 8

Atropine Side Effects

Answer 8

• Anticholinergic Effects: Remember the mneumonic:
DRY AS A BONE—Dry mucous membranes, urinary retention,constipation
MAD AS A HATTER—Restlessness, tachycardia, palpitations, HA, dizziness
RED AS A BEET—Flushed, hot, and dry skin
BLIND AS A BAT—Dilated pupils(mydriasis), blurred vision
(cycloplegia), photophobia
• Tachydysrhythmias, VT/VF
• N/V

Question 9

Atropine Interactions

Answer 9

• Anticholinergics increase vagal blockade.
• Potential adverse effects when administered with digitalis, cholinergics, neostigmine.
• Enhanced effects are possible with antihistamines, procainamide, quinidine, antipsychotics, antidepressants, benzodiazepines, phenothiazines.
• Thoroughly flush line post Na+ bicarb admin