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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

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epithelial tissue are thin tissues that covers all the exposed surfaces of the body
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Prin Reply
anatomy is the study of human body.?
Sittie
anatomy is the study of scientific human body's structure.
Sittie
Anatomy is the study of the structure of the human body and the physical relationship between its constituent parts.
Maina
Anatomy is the study of the structures of body parts
Nepi
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tribel
Anatomy is the scientific study of human body parts .
Shakinah
Anatomy is the study of structure and relationship of the body structure
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Anatomy is the study of the structure and movement of the human body
renukha
energy generation molecular transport reproduction.
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Anatomy is the study of budy structures and their relationship.
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Bonnie Reply
yes
Musi
yes
Given
No
Stephen
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Bonnie
no
Stephen
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Haemoglobin is a protein found in RBCs. Seeing as it is a protein (solid) it isn't a fluid.
jason
circulation of blood through the left side of the heart
Dorothy Reply
explain features of epithelial tissue
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function of animal cell
Ghati
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Hyden Reply
Endochondral ossification involves the replacement of hyaline cartilage with bony tissue. Most of the bones of the skeleton are formed in this manner. These bones are called endochondral bones. In this process, the future bones are first formed as hyaline cartilage models.
Sanjith
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judith Reply
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ABIGAIL
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Ochiel
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Smart
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Pires Reply
Hi guys, can questions about kinesiology be asked here? Currently pursuing kinesiology with a specialization in pedagogy
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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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