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• Blood pressure


  The pressure exerted by blood on the walls of the arteries
• Palpatory method for measuring blood pressure

  1. Palpate radial pulse

  2. Note pressure at which pulse returns after being obliterated

  3. Slowly reduce pressure in cuff
• Palpatory method


  • Only systolic pressure can be determined
  • Inaccurate, reading too low by 5-10 mmHg
  • Useful for ensuring brachial pulse is exceeded
• Auscultatory method for measuring blood pressure

  1. Raise pressure above brachial artery

  2. Gradually lower pressure while listening with stethoscope

  3. Note Korotkoff sounds - phase 1 is systolic, phase 5 is diastolic
• Oscillometric method for measuring blood pressure

  1. Utilise Pachon type oscillometer

  2. Reverse pulsation on record signals systolic

  3. Sudden decrease in oscillation size signals diastolic
• Factors maintaining pulse pressure

  • Pumping action of heart
  • Peripheral resistance
  • Amount of blood in arteries
  • Viscosity of blood
  • Elasticity of arterial walls
• Factors normally affecting arterial blood pressure

  • Time of day
  • Bodily movements and exercise
  • Pain
  • Position
  • Emotional stress
  • Age of individual
  • Build of individual
• Rise in diastolic pressure


  More significant than rise in systolic pressure, as diastolic reflects peripheral resistance and arterial wall elasticity
• Between systolic and diastolic pressure, a rise in the diastolic pressure is considered more significant than a rise in systolic pressure, since the diastolic pressure is a reflection of the peripheral resistance and the change in the elasticity of the arterial walls.