Measuring Pulse Rate: Skills (HL IB Biology)

• The contraction of the ventricles forces a large volume of blood through the arteries, which expand to accommodate this
• This can be felt as a pulse, especially in places where an artery is close to the skin surface or passes over a bone
  • For this reason, the carotid artery or radial artery can be used to measure pulse rate
    • The carotid artery runs down the side of the neck and a pulse can be felt just below the jaw
    • The radial artery passes over the wrist bones where a pulse can be felt just below the base of the thumb
• A pulse can be taken as follows:
  • Place two fingers on the radial or carotid artery and gently compress the blood vessel
  • Count the number of pulses felt for 60 seconds
    • Alternatively, you could count for 30 seconds and multiply by 2
• Do not use your thumb when taking a pulse, since it also has a pulse that can lead to inaccurate results
• There are many digital devices that can also be used to determine pulse rate
  • These include data loggers, smartwatches or fitness bands
  • They scan the blood flow through the radial artery to measure pulse rate

Measuring pulse diagram

The radial or carotid artery can be used to measure the pulse rate