What is Blood Pressure?



What is blood pressure?

Blood pressure (BP) is a measure of the pressure exerted by the blood as it flows through the arteries. It is measured in millimetres of mercury (mmHg).

The purpose of taking a blood pressure measurement may be to:

  1. Determine a person’s haemodynamic status;
  2. Gain a baseline; and
  3. Monitor for changes from the baseline.

Blood pressure measurements take into account:

  • Systolic measurements (the contraction of the ventricles) and
  • Diastolic (the ventricles are at rest and filling) measurements.

A normal systolic range for an adult is 100-140mmHg and a normal diastolic is 60- 89mmHg.

Influencing factors include but are not limited to anxiety, cardiac output, vascular resistance, blood volume and blood viscosity, age, exercise, stress, ethnicity, gender, medications, body weight, diurnal variations, disease processes, hypervolaemia and hypovolemia.

Learn more about blood pressure here: https://www.ausmed.com.au/cpd/articles/how-to-take-blood-pressure.

CPD time1m
First Published17 March 2020
Updated17 March 2020
17 March 2025
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