A pulse is the rhythmic expansion and recoil of an artery, which occurs in response to the heart’s contraction cycle. This sensation is directly linked to the heart rate, representing the number of times the heart beats per minute. Measuring the pulse provides a simple yet effective way to assess the efficiency of the circulatory system. It is a fundamental indicator used in health care to quickly evaluate a person’s overall cardiac function and blood flow.
The Mechanism Behind the Pulse
The feeling of a pulse is the detection of a pressure wave, not the actual rush of blood itself. When the left ventricle contracts (systole), it ejects blood into the aorta, causing the elastic walls of the arteries to expand rapidly. This expansion travels as a wave along the arterial network, which can be felt at various points on the body.
The pressure wave moves much faster than the blood flow, propagating through the artery walls. To detect this wave, an artery must be situated close to the skin’s surface and pressed against a firm structure, such as a bone. Pressing the artery against a bone allows the pressure wave’s force to be concentrated and felt by the fingertips, defining these spots as pulse points.
Identifying the Seven Key Pulse Points
The human body has several sites where a pulse can be felt, with seven locations being particularly useful for clinical or general assessment.
Upper Body Pulse Points
The Radial pulse is located on the inner side of the wrist, just below the base of the thumb. This is the most common site for checking the heart rate in adults due to its accessibility. The Carotid pulse is found on the side of the neck, situated in the groove between the windpipe and the neck muscle. This site is often used during emergencies to quickly confirm cardiac activity because it carries a strong pulse. The Brachial pulse is located on the inside of the upper arm or in the crease of the elbow, a site frequently used to check the pulse of infants or to measure blood pressure.
Head and Lower Body Pulse Points
The Temporal pulse is located on the side of the head, near the temple, just in front of the ear. This site is typically assessed during a comprehensive examination of the head. The Femoral pulse is found in the groin area, where the thigh meets the torso. This pulse is felt deeper in the tissue and is important for assessing circulation in the lower limbs. The Popliteal pulse is located behind the knee, requiring the knee to be slightly bent for proper palpation, and is situated deep within the popliteal fossa. Finally, the Dorsalis Pedis pulse is found on the top of the foot, typically between the first and second toes, and is used to assess the outermost circulation of the foot.
Correct Technique for Taking a Pulse
To accurately measure a pulse, correct finger placement and pressure are necessary. Use the tips of your index and middle fingers to palpate the artery, avoiding the thumb, as it contains its own pulse that could cause confusion. Apply gentle, firm pressure until a distinct throbbing sensation is felt.
Once the pulse is located, count the beats for a specific duration using a watch or clock with a second hand. A common and accurate method involves counting the beats felt in 30 seconds and then multiplying that count by two, which provides the heart rate in beats per minute (bpm).
For a quick check, counting for 15 seconds and multiplying by four is acceptable. If the pulse feels irregular or unusually slow or fast, it is best to count for a full 60 seconds to ensure the most precise measurement.