Blood pressure, although usually measured in medical institutions using a device known as a sphygmomanometer in the brachial artery, is not usually well understood from a biological point of view. Understanding the controlling physiological forces behind blood pressure is an important part of understanding how the circulatory system and the human body work.
Defining and understanding blood pressure
Blood pressure can be defined as the force or pressure of the contents of the vessel walls as it is exhaled and circulated throughout the body. This pressure is created in the vessels by the heart. In order for the heart to beat normally, the blood is forced into the arteries in waves; these waves are strong, and push the blood through the arteries, veins, and capillaries throughout the body.
There are two types of blood pressure that are monitored and recorded; systole and diastolic The numerical difference between these two types of blood pressure is known as pulse pressure. blood pressure is the level of blood pressure at the peak of the contraction of the ventricles, or the point at which the heart beats, and blood is pumped out of the ventricles. twisted The second type of blood pressure blood pressure, which is called diastolic blood pressure, is measured in the ventricular phase . relaxation, or the time between heartbeats where the ventricles are relaxed and filled with blood again.
Abnormal blood pressure
The average systolic blood pressure of each healthy person between the ages of 20 and 30 is about 120, while the average diastolic blood pressure is 75. This example of blood pressure would be read as 120/75 (one hundred and twenty five). This is normal, healthy blood.
When someone has too high blood pressure, it is referred to as hypertension. Hypertension is typically diagnosed in individuals with blood pressure over 140/90 and is common among Americans. Hypertension can cause damage to vessel walls, an increase in cholesterol build-up within the vessels and can lead to cardiac disease and heart failure . .
Individuals with especially low blood pressure are diagnosed as hypotension. Hypotension is typically diagnosed when an individual’s lower blood pressure than 80/60 is recorded. Hypotension can pose risks to the individual’s health, such as fainting, circulatory failure (stroke), weak pulse and urinary suppression. Additionally, individuals suffering from hypotension often have blood pressures that cannot be accurately measured and recorded.
Peripheral Resistance
Peripheral resistance is best defined as the opposing forces acting on blood flow within the veins. Pressure, as in blood pressure, cannot be produced without the opposite force of resistance which results in pressure. When talking about terms related to blood pressure, blood viscosity, vessel length and vessel radius all have a direct impact on the amount of peripheral resistance.
Other things that affect blood pressure
A typical blood pressure reading can best be taken in a relaxed state, as blood pressure readings can show elevated numbers during periods of high physical activity. There are several factors that can affect the blood pressure reading, such as the individual’s age or weight. Blood pressure typically increases as each person ages due to the body’s decreasing ability to accommodate systolic pressure. Additionally, the specific volume of an individual’s blood contributes to their blood pressure. Medications, both prescription and over the counter, can also affect blood pressure readings. Finally, resistance to blood flow throughout the body, such as from excessive cholesterol built up within the vessels, or constriction, or eroding vessels, can also contribute to poor blood pressure readings.
References
Saladin, Kenneth S.. Anatomy & physiology: the unity of form and function. 5th ed. New York: McGraw-Hill, 2010. Print.
