Week 28 Case study

• People with high blood pressure


  At greater risk of having a hemorrhagic stroke
• How high blood pressure causes hemorrhagic stroke


  1. Weakened or damaged blood vessel wall

  2. High blood pressure causes area to rupture

  3. Blood leaks out of blood vessels into surrounding tissues
• Reducing salt intake and taking a diuretic

  Controls hypertension
• Rationale for reducing salt intake and taking a diuretic to control hypertension

  • Blood pressure increases if the circulating blood volume increases
  • Restricting salt decreases fluid retention in extracellular compartment
  • Diuretics decrease blood volume
• Blocking the action of a vasoconstrictor

  Lowers blood pressure
• How blocking a vasoconstrictor lowers blood pressure

  • Resistance is inversely proportional to the radius of the blood vessels
  • Blocking vasoconstrictor dilates blood vessels
  • Resistance and blood pressure decrease
• How calcium channel blockers lower blood pressure

  • Blocking calcium ion entry decreases force of cardiac contraction
  • Decreases contractility of vascular smooth muscle
  • Both effects lower blood pressure