LPN Nursing Fundamentals Related

Review LPN Nursing Fundamentals related questions and content

The nurse manager is conducting an educational session for the nurses on non-selective beta-adrenergic blockers ( $\beta$ blockers). How should the nurse manager accurately describe the mechanism of action of these medications? List the options in order from first to last.

  • A. Heart rate and blood pressure are decreased
  • B. Epinephrine and norepinephrine actions are blocked
  • C. Beta₁ and betaâ‚‚ receptor sites are blocked
  • D. Cardiac workload and oxygen demand decreases
Correct Answer: C

Rationale: Non-selective beta-adrenergic blockers (e.g., propranolol) inhibit the sympathetic nervous system's effects on beta₁ (heart) and beta₂ (lungs, vessels) receptors. The mechanism sequence is: (1) Beta₁ and beta₂ receptor sites are blocked (C), (2) Epinephrine and norepinephrine actions are blocked (B), (3) Heart rate and blood pressure are decreased (A), (4) Cardiac workload and oxygen demand decreases (D). Blocking beta receptors (C) is the initial step, preventing catecholamines (B) from binding, which reduces heart rate and vasoconstriction (A), ultimately lowering myocardial oxygen demand (D). Incorrect sequencing, like starting with heart rate reduction, skips the pharmacological basis. The CSV requires one answer, so C is chosen as the foundational step. Rationale: Beta blockade directly inhibits receptor activation, a primary action taught in pharmacology education, leading to downstream effects critical for conditions like hypertension or angina, ensuring nurses understand the drug's systemic impact.