A nurse is caring for a neonate born with a congenital heart abnormality.
To better help the parents understand the impact of this disorder, the nurse begins by describing the unusual flow of blood through the heart which takes what course?

Choice A rationale

Evidence of human fetal risk would categorize the drug as Category D or X, not Category B.

Choice B rationale

This statement aligns more with Category C drugs, where animal studies show adverse effects, but not Category B.

Choice C rationale

This describes Category A drugs, not Category B.

Choice D rationale

Category B drugs have shown no risk in animal studies but lack adequate human studies, fitting this description.

Choice A rationale

Class I antiarrhythmic drugs block sodium channels, affecting phase 0 of the action potential, not phase 3.

Choice B rationale

Class IV antiarrhythmic drugs block calcium channels, which affects phase 2 of the action potential and slows heart rate and conduction.

Choice C rationale

Class III antiarrhythmic drugs block potassium channels, prolonging phase 3 of the action potential. This results in a prolonged repolarization period, reducing the risk of arrhythmia.

Choice D rationale

Class II antiarrhythmic drugs are beta-blockers that primarily affect phase 4 of the action potential, reducing heart rate and conduction, but they do not block potassium channels.