Pulse
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In medicine, a person's pulse is the arterial palpation of a heartbeat.[1] It can be palpated in any place that allows for an artery to be compressed against a bone, such as at the neck (carotid artery), at the wrist (radial artery), behind the knee (popliteal artery), on the inside of the elbow (brachial artery), and near the ankle joint (posterior tibial artery). The pulse rate can also be measured by measuring the heart beats directly (the apical pulse).
Physiology
Pressure waves move along the artery walls, which are pliable; these waves are not caused by the forward movement of the blood itself, however. When the heart contracts, blood is ejected into the aorta and the aorta stretches. At this point, the wave of distention (pulse wave) is pronounced but relatively slow-moving (3–6 m/s). As it travels towards the peripheral blood vessels, it gradually diminishes and becomes faster. In the large arterial branches, its velocity is 7–10 m/s; in the small arteries, it is 15–35 m/s. The pressure pulse is transmitted fifteen or more times more rapidly than the blood flow.
PULSE is also used to denote the frequency of the heart beat, usually measured in beats per minute[2]. In most people, the pulse is an accurate measure of heart rate. Under certain circumstances, including arrhythmias, some of the heart beats are ineffective, and the aorta is not stretched enough to create a palpable pressure wave. The pulse is too irregular and the heart rate can be (much) higher than the pulse rate. In this case, the heart rate should be determined by auscultation of the heart apex, in which case it is not the pulse. The pulse deficit (difference between heart beats and pulsations at the periphery) should be determined by simultaneous palpation at the radial artery and auscultation at the heart apex.
Ranges
A normal pulse rate for a healthy adult, while resting, can range from 60 to 100 beats per minute (BPM), although well-conditioned athletes may have a healthy pulse rate lower than 60 BPM. Bradycardia occurs when the pulse rate is below 60 per minute, whereas tachycardia occurs when the rate is above 100 BPM. During sleep, the pulse can drop to as low as 40 BPM; during strenuous exercise, it can rise as high as 150–200 BPM. Generally, pulse rates are higher in infants and young children. The resting heart rate for an infant is usually close to an adult's pulse rate during strenuous exercise (average 110 BPM for an infant).
Evaluation
A collapsing pulse is a sign of hyperdynamic circulation.
Several pulse patterns can be of clinical significance. These include:
The strength of the pulse can also be reported:[3][4]
- 0 = Absent
- 1 = Barely palpable
- 2 = Easily palpable
- 3 = Full
- 4 = Aneurysmal or bounding
Common pulse sites
Upper limb
- Axillary pulse: located inferiorly of the lateral wall of the axilla
- Brachial pulse: located on the inside of the upper arm near the elbow, frequently used in place of carotid pulse in infants (brachial artery)
- Radial pulse: located on the lateral of the wrist (radial artery). It can also be found in the anatomical snuff box.
- Ulnar pulse: located on the medial of the wrist(ulnar artery).
Lower limb
- Femoral pulse: located in the thigh, halfway between the pubic symphysis and anterior superior iliac spine (femoral artery).
- Popliteal pulse: Above the knee in the popliteal nasal, found by holding the bent knee. The patient bends the knee at approximately 124°, and the physician holds it in both hands to find the popliteal artery in the pit behind the knee.
- Dorsalis pedis pulse: located on top of the foot (dorsalis pedis artery).
- Tibialis posterior pulse: located on the medial side of the ankle around medial malleolus (posterior tibial artery).
Head/neck
- Carotid pulse: located in the neck (carotid artery). The carotid artery should be palpated gently and while the patient is sitting or lying down. Stimulating its baroreceptors with low palpitation can provoke severe bradycardia or even stop the heart in some sensitive persons. Also, a person's two carotid arteries should not be palpated at the same time. Doing so may limit the flow of blood to the head, possibly leading to fainting or brain ischemia. It can be felt between the anterior border of the sternocleidomastoid muscle, above the hyoid bone and lateral to the thyroid cartilage.
- Facial pulse: located on the mandible (lower jawbone) on a line with the corners of the mouth (facial artery).
- Temporal pulse: located on the temple directly in front of the ear (superficial temporal artery).
Torso
- Apical pulse: located in the 4.5th or 5th left intercostal space, just to the left of the sternum. In contrast with other pulse sites, the apical pulse site is unilateral, and measured not under an artery, but below the heart itself (more specifically, the apex of the heart).
See also
References
- ^ "pulse" at Dorland's Medical Dictionary
- ^ MedlinePlus Encyclopedia: Pulse
- ^ "www.meddean.luc.edu". Retrieved 2009-05-20.
- ^ "Vascular Surgery, University of Kansas School of Medicine". Retrieved 2009-05-20.