Blood pressure measurements include two readings – a systolic pressure and a diastolic pressure
- The systolic pressure is a higher value that represents the pressure in the vessel when the heart is contracting (i.e. pulse flow)
- The diastolic pressure is a lower value that represents the pressure in the vessel when the heart is relaxing
Blood pressure is measured in arteries using a sphygmomanometer (veins do not have sufficient pressure to be easily detected)
- The sphygmomanometer is a blood pressure cuff that cuts off circulation to a region (typically the brachial artery in the arm)
- The pressure of the cuff is slowly released until a pulse can be audibly detected with a stethoscope (systolic pressure)
- The pressure continues to be released from the cuff until a pulse can no longer be audibly detected (diastolic pressure)
- A normal blood pressure for a healthy adult is approximately 120 / 80 mmHg
Measuring Blood Pressure Using a Sphygmomanometer