CPR Cardiac Arrest Pharmacology 3 — Questions and Answers
Question 1: In a patient with suspected beta-blocker overdose cardiac arrest, which high-dose therapy may be considered?
- High-dose atropine 3 mg IV
- High-dose epinephrine up to 0.2 mg/kg IV (Correct answer)
- High-dose calcium chloride 20 mg/kg IV
- High-dose lidocaine 3 mg/kg IV
Correct answer: High-dose epinephrine up to 0.2 mg/kg IV
High-dose epinephrine (up to 0.2 mg/kg) may overcome beta-receptor blockade in refractory beta-blocker-induced cardiac arrest.
Question 2: What is the recommended IV/IO dose of adenosine for the FIRST dose when treating stable SVT?
- 3 mg rapid IV push
- 6 mg rapid IV push (Correct answer)
- 12 mg rapid IV push
- 18 mg rapid IV push
Correct answer: 6 mg rapid IV push
The initial adenosine dose for SVT is 6 mg given as a rapid IV push followed immediately by a 20 mL saline flush.
Question 3: Which statement about atropine use in asystole is MOST accurate per current AHA guidelines?
- Atropine 1 mg every 3–5 min is first-line for asystole
- Atropine has been removed from the asystole/PEA algorithm (Correct answer)
- Atropine 0.5 mg is used to increase heart rate in asystole
- Atropine reverses asystole by blocking vagal tone
Correct answer: Atropine has been removed from the asystole/PEA algorithm
Current AHA guidelines removed atropine from the cardiac arrest algorithm because evidence showed no benefit in asystole or PEA.
Question 4: A patient in calcium channel blocker overdose arrest is unresponsive to standard ACLS. Which antidote should be considered?
- Physostigmine
- High-dose insulin euglycemic therapy (Correct answer)
- Protamine sulfate
- Vitamin K
Correct answer: High-dose insulin euglycemic therapy
High-dose insulin euglycemic therapy (1 unit/kg bolus followed by infusion) improves myocardial carbohydrate metabolism in calcium channel blocker toxicity.
Question 5: What is the IO dose of epinephrine in adult cardiac arrest?
- 0.5 mg of 1:1,000 solution
- 1 mg of 1:10,000 solution (Correct answer)
- 2 mg of 1:10,000 solution
- 1 mg of 1:1,000 solution
Correct answer: 1 mg of 1:10,000 solution
The standard epinephrine dose for adult cardiac arrest via IO route is 1 mg of 1:10,000 (0.1 mg/mL) solution every 3–5 minutes.
Question 6: Which drug is used to treat torsades de pointes that degenerates into pulseless VT/VF during cardiac arrest?
- Amiodarone 300 mg IV
- Magnesium sulfate 1–2 g IV (Correct answer)
- Lidocaine 1.5 mg/kg IV
- Procainamide 20 mg/min infusion
Correct answer: Magnesium sulfate 1–2 g IV
Magnesium sulfate 1–2 g IV/IO is the treatment of choice for torsades de pointes-related VT/VF during cardiac arrest.
Question 7: A paramedic administers sodium bicarbonate in a patient with prolonged cardiac arrest (>10 min). What is the PRIMARY concern with this intervention?
- Hypokalemia worsening arrhythmia
- Paradoxical intracellular acidosis and hyperosmolarity (Correct answer)
- Immediate hypernatremia causing seizures
- Alkalosis reversing epinephrine effects
Correct answer: Paradoxical intracellular acidosis and hyperosmolarity
Sodium bicarbonate can cause paradoxical intracellular acidosis (CO2 diffuses into cells) and hyperosmolarity, potentially worsening cellular function.
CPR Cardiac Arrest Pharmacology 3
In a patient with suspected beta-blocker overdose cardiac arrest, which high-dose therapy may be considered?