Definition and Measurement of Blood Pressure
- Blood pressure is the pressure of circulating blood against the walls of blood vessels.
- It is measured in terms of systolic pressure over diastolic pressure.
- Blood pressure is usually measured in a brachial artery using a sphygmomanometer.
- It is expressed in millimeters of mercury or kilopascals.
- Pulse pressure refers to the difference between systolic and diastolic pressures, while mean arterial pressure is the average pressure during a cardiac cycle.
Importance of Blood Pressure as a Vital Sign
- Blood pressure is one of the vital signs used by healthcare professionals to evaluate a patient's health.
- Normal resting blood pressure in adults is approximately 120/80 mmHg.
- Globally, the average blood pressure has remained relatively stable since 1975.
- High blood pressure is a risk factor for various diseases, including stroke, heart disease, and kidney failure.
- Low blood pressure can also have adverse effects on health.
Methods of Blood Pressure Measurement
- Traditional method: auscultation through a stethoscope using an aneroid gauge or a mercury-tube sphygmomanometer.
- Semi-automated methods have become common due to concerns about mercury toxicity.
- Modern devices validated to international standards achieve accurate readings.
- Most semi-automated methods use oscillometry to measure blood pressure.
- Ambulatory blood pressure measurement is advocated by some authorities for diagnosing hypertension.
Factors Influencing Blood Pressure
- Blood pressure is influenced by cardiac output, systemic vascular resistance, blood volume, and arterial stiffness.
- It varies depending on a person's situation, emotional state, activity, and relative health.
- Baroreceptors regulate blood pressure in the short term by influencing the nervous and endocrine systems.
- Hypertension and hypotension can have various causes and may be of sudden or long-term onset.
- People maintaining lower arterial pressures have better long-term cardiovascular health.
Blood Pressure and Age
- Fetal blood pressure is primarily regulated by the fetal heart during pregnancy.
- Blood pressure ranges in children are lower than in adults and depend on height.
- In aging adults, systolic blood pressure tends to rise from early adulthood onward.
- Diastolic pressure also rises but starts to fall earlier in mid-life.
- Pulse pressure increases significantly after the age of 40, attributed to increased arterial stiffness.
Blood pressure Data Sources
| Reference | URL |
|---|---|
| Glossary | https://www.alternix.com/blogs/glossary-of-terms/blood-pressure |
| Wikipedia | http://en.wikipedia.org/wiki/Blood_pressure |
| Wikidata | https://www.wikidata.org/wiki/Q82642 |
| Knowledge Graph | https://www.google.com/search?kgmid=/m/02mx00 |
