Lecture Notes: Cardiovascular Drugs - Pharmacology for Nursing (Professor Hoffman)

Topic 6C: Antihypertensives

Learning Objectives:

• ACE inhibitors
• ARBs
• Beta blockers
• Calcium channel blockers

Key Topics

ACE Inhibitors

• Suffix: '-pril' (e.g., Lisinopril)
• Mechanism: Angiotensin-converting enzyme inhibitor (Blocks conversion of Angiotensin I to Angiotensin II)
• Effects:
  • Causes vasodilation
  • Reduces blood pressure
  • Decreases workload on the heart
• Uses:
  • Hypertension
  • Heart failure
• Side Effects:
  • Hypotension
  • Cough
  • Neutropenia, agranulocytosis
  • Angioedema
  • Hyperkalemia
• Nursing Considerations:
  • Contraindicated in pregnancy (black box warning)
  • Monitor blood pressure
  • Persistent cough may require switching to ARBs
  • Watch for facial swelling or airway pressure (angioedema)
  • Monitor potassium levels due to risk of hyperkalemia

ARBs (Angiotensin Receptor Blockers)

• Suffix: '-sartan' (e.g., Losartan)
• Mechanism: Block receptor sites for Angiotensin II
• Effects:
  • Similar to ACE inhibitors but without causing a cough
  • Vasodilation
  • Decrease aldosterone leading to potassium retention
• Uses:
  • Hypertension
  • Heart failure
• Side Effects:
  • Hypotension
  • Angioedema
  • Hyperkalemia
• Nursing Considerations:
  • Still a black box warning for pregnancy
  • Similar monitoring as ACE inhibitors

Calcium Channel Blockers

• Mechanism: Block calcium movement into cells, affecting both heart and arterial muscles
• Effects:
  • Reduces heart rate (slows conduction)
  • Decreases contractility (strength of contractions)
  • Causes arterial dilation
• Uses:
  • Hypertension
  • Angina
  • Tachycardia
• Side Effects:
  • Hypotension
  • Bradycardia
  • Edema
  • Liver damage
• Nursing Considerations:
  • Monitor blood pressure and heart rate
  • Teach dosing compliance
  • Avoid grapefruit juice (can cause drug toxicity)

Beta Blockers

• Suffix: '-olol' (e.g., Atenolol, Propranolol)
• Mechanism: Block beta-1 receptors, reducing sympathetic nervous system effects on the heart
• Effects:
  • Decrease heart rate
  • Decrease contractility
• Uses:
  • Hypertension
  • Tachyarrhythmias
  • Angina
• Side Effects:
  • Hypotension
  • Bradycardia
  • Worsening heart failure
  • Bronchoconstriction (especially in non-selective beta blockers)
• Nursing Considerations:
  • Monitor blood pressure and heart rate
  • In diabetic patients, monitor blood glucose levels (affect glucose release from the liver)
  • Ensure patient compliance
  • Teach patients to check their own pulse
  • Taper dose slowly if discontinuing

Summary

• Each class of antihypertensive drugs works via different mechanisms but has common goals of reducing blood pressure and cardiac workload.
• Understanding side effects and nursing considerations is crucial for safe and effective patient care.