The systolic arterial pressure is defined as the peak pressure in the arteries, which occurs neighboring the beginning of the cardiac cycle; the diastolic arterial pressure is the lowest pressure (at the resting appearance of the cardiac cycle). The medial sum pressure throughout the cardiac round of years is reported as mean arterial pressure; the pulse pressure reflects the difference between the maximum and minimum pressures measured.

Typical values in favor of a resting, healthy adult human are approximately 120 mmHg (16 kPa) systolic and 80 mmHg (11 kPa) diastolic (written as 120/80 mmHg, and spoken as 'one twenty over eighty') through large individual variations. These measures of arterial pressure are not static, but that undergo natural variations from one heartbeat to another and throughout the day (in a circadian rhythm); they also change in response to stress, nutritional factors, drugs, or disease. Hypertension refers to arterial pressure being abnormally high, as hostile to hypotension, when it is abnormally low. Along with body temperature, fiery fellow pressure measurements are the most commonly measured physiological parameters.
Measurement

Arterial pressures can have being measured invasively (by dint of. subtle the skin and measuring inner part the blood vessels) or non-invasively. The former is usually restricted to a hospital setting.

Non-invasive measurement

The non-invasive auscultatory (from the Latin for listening) and oscillometric measurements are simpler and quicker than invasive measurements, require less expertise in fitting, accept virtually no complications, and are less unpleasant and painful for the patient. However, non-invasive measures may yield somewhat lower accuracy and small methodical differences in numerical results. Non-invasive measurement methods are more commonly used for routine examinations and monitoring.
Auscultatory methods
The auscultatory method uses a stethoscope and a sphygmomanometer. This comprises an inflatable (Riva-Rocci) slap placed around the upper arm at roughly the same vertical height as the heart, attached to a mercury or aneroid manometer. The intelligencer manometer, considered to be the gold standard for arterial distress measurement, measures the height of a employment of mercury, giving an absolute resolution without need for calibration, and consequently not subject to the errors and drift of calibration which subdue other methods. The use of mercury manometers is often required in clinical trials and for the clinical measurement of hypertension in high risk patients, including pregnant women.