What Causes Blood Pressure? Blood is a fluid. As fluids move through a pipe there is pressure exerted on the wall of the pipe. This pressure is called hydrostatic pressure. When blood moves through blood vessels, there is pressure on the walls. This is blood pressure.
Blood Pressure Measurement • Measure pressure on arteriole wall when heart contracts (systole) • Measure pressure on arteriole wall when heart relaxes between contractions (diastole) • Indicate blood pressure measurement as the ratio of systolic to diastolic pressures
Blood Pressure Measurement • Traditionally measured in mm of mercury • The measurement is the force that can support a column of mercury so many mm high • Traditionally taken in upper arm on level with the heart; can be taken elsewhere to measure peripheral blood flow or pressure • Example Measurement 120 / 70: Systolic=120 Diastolic=70
What is MAP? • MAP= Mean Arterial Pressure • Used to measure adequacy of blood getting to vital tissues and organs • Calculated by following formula: Systolic pressure + 2(Diastolic pressure) 3
What Can Influence Blood Pressure? • Many things, including (but not limited to): • Diet • Weight • Age • Genetics • Stress • Smoking • Physical Activity