Long-term hypertension is more common than long-term hypotension. Long-term hypertension is a risk factor for many diseases, including stroke, heart disease, and kidney failure. Both hypertension and hypotension have many causes and may be of sudden onset or of long duration.

In the short term, blood pressure is regulated by baroreceptors, which act via the brain to influence the nervous and the endocrine systems.Д«lood pressure that is too low is called hypotension, pressure that is consistently too high is called hypertension, and normal pressure is called normotension. Д«lood pressure is influenced by cardiac output, systemic vascular resistance and arterial stiffness and varies depending on situation, emotional state, activity, and relative health/disease states. IntraвЂ“cuff pressure accompanying heartbeatвЂ“induced changes in the volume of each pulse). Most of these semi-automated methods measure blood pressure using oscillometry (measurement by a pressure transducer in the cuff of the device of small oscillations of

Early automated alternatives to mercury-tube sphygmomanometers were often seriously inaccurate, but modern devices validated to international standards achieve an average difference between two standardized reading methods of 5В mm Hg or less, and a standard deviation of less than 8В mm Hg. However, semi-automated methods have become common, largely due to concerns about potential mercury toxicity, although cost, ease of use and applicability to ambulatory blood pressure or home blood pressure measurements have also influenced this trend. Auscultation is still generally considered to be the gold standard of accuracy for non-invasive blood pressure readings in clinic. Traditionally, a health-care worker measured blood pressure non-invasively by auscultation (listening) through a stethascope for sounds in one arm's artery as the artery was squeezed, closer to the heart, by an aneroid gauge or a mercury-tube sphygmomanometer.

127/79 mmHg in men and 122/77 mmHg in women, although these average data mask significantly diverging regional trends. Globally, the average blood pressure, age standardized, has remained about the same since 1975 to the present, at approx. Normal resting blood pressure, in an adult is approximately 120 millimetres of mercury (16В kPa) systolic over 80 millimetres of mercury (11В kPa) diastolic, denoted as '120/80В mmHg'. It is measured in millimeters of mercury ( mmHg) above the surrounding atmospheric pressure.Д«lood pressure is one of the vital signs-together with respiratory rate, heart rate, oxygen saturation, and body temperature-that healthcare professionals use in evaluating a patient's health. Blood pressure is usually expressed in terms of the systolic pressure (maximum pressure during one heartbeat) over diastolic pressure (minimum pressure between two heartbeats) in the cardiac cycle. When used without qualification, the term 'blood pressure' refers to the pressure in the large arteries. Most of this pressure results from the heart pumping blood through the circulatory system. A healthcare worker measuring blood pressure using a sphygmomanometer.Д«lood pressure ( BP) is the pressure of circulating blood against the walls of blood vessels.

Woman blood pressure chart