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Mean arterial pressure

Mean arterial pressure (MAP) represents the “average” pressure of blood in the arteries, that is, the average force driving blood into vessels that serve the tissues. Mean is a statistical concept and is calculated by taking the sum of the values divided by the number of values. Although complicated to measure directly and complicated to calculate, MAP can be approximated by adding the diastolic pressure to one-third of the pulse pressure or systolic pressure minus the diastolic pressure:

MAP = diastolic BP +  (systolic-diastolic BP) 3 MathType@MTEF@5@5@+=feaagyart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaeytaiaabgeacaqGqbGaaeiiaiaab2dacaqGGaGaaeizaiaabMgacaqGHbGaae4CaiaabshacaqGVbGaaeiBaiaabMgacaqGJbGaaeiiaiaabkeacaqGqbGaaeiiaiaabUcacaqGGaWaaSaaaeaacaqGOaGaae4CaiaabMhacaqGZbGaaeiDaiaab+gacaqGSbGaaeyAaiaabogacaqGTaGaaeizaiaabMgacaqGHbGaae4CaiaabshacaqGVbGaaeiBaiaabMgacaqGJbGaaeiiaiaabkeacaqGqbGaaeykaaqaaiaabodaaaaaaa@5BD7@

In [link] , this value is approximately 80 + (120 − 80) / 3, or 93.33. Normally, the MAP falls within the range of 70–110 mm Hg. If the value falls below 60 mm Hg for an extended time, blood pressure will not be high enough to ensure circulation to and through the tissues, which results in ischemia    , or insufficient blood flow. A condition called hypoxia    , inadequate oxygenation of tissues, commonly accompanies ischemia. The term hypoxemia refers to low levels of oxygen in systemic arterial blood. Neurons are especially sensitive to hypoxia and may die or be damaged if blood flow and oxygen supplies are not quickly restored.

Pulse

After blood is ejected from the heart, elastic fibers in the arteries help maintain a high-pressure gradient as they expand to accommodate the blood, then recoil. This expansion and recoiling effect, known as the pulse    , can be palpated manually or measured electronically. Although the effect diminishes over distance from the heart, elements of the systolic and diastolic components of the pulse are still evident down to the level of the arterioles.

Because pulse indicates heart rate, it is measured clinically to provide clues to a patient’s state of health. It is recorded as beats per minute. Both the rate and the strength of the pulse are important clinically. A high or irregular pulse rate can be caused by physical activity or other temporary factors, but it may also indicate a heart condition. The pulse strength indicates the strength of ventricular contraction and cardiac output. If the pulse is strong, then systolic pressure is high. If it is weak, systolic pressure has fallen, and medical intervention may be warranted.

Pulse can be palpated manually by placing the tips of the fingers across an artery that runs close to the body surface and pressing lightly. While this procedure is normally performed using the radial artery in the wrist or the common carotid artery in the neck, any superficial artery that can be palpated may be used ( [link] ). Common sites to find a pulse include temporal and facial arteries in the head, brachial arteries in the upper arm, femoral arteries in the thigh, popliteal arteries behind the knees, posterior tibial arteries near the medial tarsal regions, and dorsalis pedis arteries in the feet. A variety of commercial electronic devices are also available to measure pulse.

Pulse sites

This image shows the pulse points in a woman’s body.
The pulse is most readily measured at the radial artery, but can be measured at any of the pulse points shown.

Questions & Answers

why are cells small
Hajiahamdy Reply
what is the change if take normal water in our body
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What are variations in physiology
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pls let's talk about d difference between mitosis and meiosis
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through remodeling and formation of new bones
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please what is it
Monica
what is blood pressure
HALLELUYAH
what is blood pressure reading
HALLELUYAH
sketch and label blood vessels
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veins is........
KING
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join
Hajiahamdy
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Abraham Reply
what is Endocrine system?
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which secrete hormones and other products direct into the blood
Aadi
Cell is basic, structural and functional unit of life
Kabuja Reply
The cell is the structural and functional unit of all living organisms, and is sometimes called the "building block of life." Some organisms, such as bacteria, are unicellular, consisting of a single cell.
Br_
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Rachel
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hey
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what is the basic function of the lymphatic system
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The other main function is that of defense in the immune system. Lymph is very similar to blood plasma: it contains lymphocytes. It also contains waste products and cellular debris together with bacteria and proteins. Associated organs composed of lymphoid tissue are the sites of lymphocyte producti
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the function of lymphatic system are 1fluid balance 2 lipid absorption and 3 defence
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destroyed microognism
Usman
lymphatic systems main function is to transport lymph
Colleen
may i know the meaning of infestation of parasite?
Aminiely
Which of the following accurately describe external respirations
Robin Reply
different between anatomy and physiology
Samwel Reply
anatomy is the study of STRUCTURE of the body while physiology is the study of the function of the part of the body
Gborgbor
Anatomy deals with the structure and parts of the body while physiology is the function of the the body parts
Archie
not understanding what is a cell
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its the fundamental unit of life or its the primary step in which two or more cell combine to form a tissue .
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Is the smallest structural and functional unit of life
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cell is the basic you unit of life
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what is hydroxyapitate
Ellen
Hydroxyapatite, also called hydroxylapatite, is a naturally occurring mineral form of calcium apatite with the formula Ca₅(PO₄)₃, but it is usually written Ca₁₀(PO₄)₆(OH)₂ to denote that the crystal unit cell comprises two entities. Hydroxyapatite is the hydroxyl endmember of the complex apatite gro
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osteomalacia is where inorganic or mineral which is calcium and phosphorus are removed from a bone....this will make the bone become flexible n in children is called ricket
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wat work does anatomy do in the hospital and can they get work fast after finishing
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what is the meaning of suture?
praba Reply
it is a protective layer of brain
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it is a kind of non movable joint present between skull bones
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suture is an example of fibrous joint and is synatrosys(is not movable)
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a junction between the sclerites of an imsect's body
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Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
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