CPR Cardiac Arrest Pharmacology 2 — Questions and Answers
Question 1: What is the recommended dose of vasopressin that may be used as an alternative to the first or second dose of epinephrine in cardiac arrest?
- 20 units IV/IO
- 40 units IV/IO (Correct answer)
- 60 units IV/IO
- 80 units IV/IO
Correct answer: 40 units IV/IO
Vasopressin 40 units IV/IO may replace the first or second dose of epinephrine in cardiac arrest per older AHA guidelines.
Question 2: A patient in refractory VF has received 3 shocks and 300 mg amiodarone. What is the correct supplemental dose of amiodarone?
- 75 mg IV
- 100 mg IV
- 150 mg IV (Correct answer)
- 300 mg IV
Correct answer: 150 mg IV
After an initial 300 mg amiodarone dose, a single supplemental dose of 150 mg IV/IO may be given for refractory VF/pVT.
Question 3: Which electrolyte disturbance is a Class I indication for magnesium sulfate administration during cardiac arrest?
- Hyperkalemia
- Hypocalcemia
- Hypomagnesemia-induced torsades de pointes (Correct answer)
- Hyponatremia
Correct answer: Hypomagnesemia-induced torsades de pointes
Magnesium sulfate 1–2 g IV is a Class I indication specifically for torsades de pointes (polymorphic VT) associated with hypomagnesemia.
Question 4: During a cardiac arrest secondary to tricyclic antidepressant overdose, which drug is the treatment of choice to reverse cardiotoxicity?
- Flumazenil
- Sodium bicarbonate (Correct answer)
- Calcium gluconate
- Naloxone
Correct answer: Sodium bicarbonate
Sodium bicarbonate alkalinizes the blood and reverses TCA-induced sodium channel blockade, narrowing the QRS and improving myocardial function.
Question 5: What is the primary mechanism by which epinephrine improves outcomes in cardiac arrest?
- Beta-1 stimulation increasing heart rate
- Alpha-1 vasoconstriction increasing coronary perfusion pressure (Correct answer)
- Beta-2 bronchodilation improving oxygenation
- Direct defibrillation of the myocardium
Correct answer: Alpha-1 vasoconstriction increasing coronary perfusion pressure
Epinephrine's alpha-1 adrenergic effect causes peripheral vasoconstriction, raising aortic diastolic pressure and thus coronary perfusion pressure during CPR.
Question 6: A patient arrests after administration of succinylcholine and develops peaked T-waves on the monitor. Which drug should be given first?
- Sodium bicarbonate
- Insulin and dextrose
- Calcium chloride (Correct answer)
- Kayexalate
Correct answer: Calcium chloride
Calcium chloride (or gluconate) immediately stabilizes the myocardial membrane and is the first intervention for hyperkalemia-induced cardiac arrest.
Question 7: Lidocaine is considered an acceptable alternative to amiodarone in which arrest rhythm?
- Asystole
- PEA with narrow QRS
- Refractory ventricular fibrillation (Correct answer)
- Complete heart block
Correct answer: Refractory ventricular fibrillation
Lidocaine 1–1.5 mg/kg IV/IO is an acceptable alternative antiarrhythmic for shock-refractory VF/pVT when amiodarone is unavailable.
CPR Cardiac Arrest Pharmacology 2
What is the recommended dose of vasopressin that may be used as an alternative to the first or second dose of epinephrine in cardiac arrest?