3-1. WHAT IS A PULSE?
A pulse is when the left ventricle of the heart contracts. When this happens, blood is suddenly pushed from the ventricle to the main artery (aorta). This sudden forcing of blood from the heart into the arteries causes two things to happen.
a. Artery Expansion. The sudden rush of blood increases the volume of blood in the arteries. In order to accept this increased volume, the arteries expand (stretch). As the arteries quickly contract (go back to normal size), blood is forced from the arteries, through the capillaries, and into the veins.
b. Pulse. In addition to the expansion of the arteries, a "wave" travels through the arteries. This wave is the pulse. All arteries have a pulse, but the pulse is easier to feel (palpate) when the artery is near the surface of the body.
3-2. WHAT IS PULSE RATE?
The pulse rate is the number of times that you can feel a pulse wave passing a point in one minute. Since a pulse wave occurs whenever the heart beats, the pulse rate equals the heartbeat rate. However, "taking a patient's pulse" means more than just determining his pulse rate. It also includes noting certain other factors about the pulse.
3-3. WHAT FACTORS ARE NOTED WHEN TAKING A PATIENT'S PULSE?
When taking a patient's pulse, you should note the patient's pulse rate, the strength of the pulse, and the regularity of the pulse. Most of the pulse characteristics discussed in this paragraph are illustrated in figure 3-1.
a. Pulse Rate.
b. Strength. The strength (force) of the pulse is determined by the amount of blood forced into the artery by the heartbeat. A normal pulse has a normal strength. You will be able to identify a normal strength pulse with practice.
c. Rhythm. Rhythm refers to the evenness of the beats. In a regular pulse, the time between beats is the same (constant) and the beats are of the same strength.
Figure 3-1. Pulse patterns.
3-4. WHICH ARTERY IS PALPATED WHEN A PULSE IS TAKEN?
There are several sites on the body where a pulse is normally taken. All arteries have a pulse, but it is easier to palpate (feel) the pulse at certain locations. It is easier to feel the pulse when the artery is near the surface of the skin and when there is firm tissue (such as a bone) beneath the artery. The three most common sites are the radial (wrist), carotid (throat), and brachial (inside of elbow). These and other sites are discussed below and illustrated in figure 3-2. The site or sites that you choose to use may vary depending upon the condition of the patient. For example, suppose that you are assisting someone who is bleeding severely from a wound in his thigh. After giving the person first aid to stop the bleeding, you will check the person's pulse at a point below the injury to make sure that your bandage has not cut off the blood circulation to the lower leg. You may take the pulse at the popliteal (behind the knee) site, the dorsalis pedis (top of the foot) site, and/or the posterior tibial (back of the ankle) site.
a. Radial. The radial pulse (the pulse taken using the radial artery) is taken at a point where the radial artery crosses the bones of the wrist. If the patient's hand is turned so that the palm is up, the radial pulse is taken on the thumb side of top side of the wrist.
b. Carotid. The carotid pulse is taken on either side of the trachea (windpipe). The best location is the grooves located to the right and to the left of the larynx (Adam's apple).
c. Brachial. The brachial pulse is taken in the depression located about one-half inch above the crease on the inside (not the bony side) of the elbow. This site is used when taking the patient's blood pressure.
Figure 3-2. Sites for taking a pulse.
d. Temporal. The temporal pulse is taken in the temple area on either side of the head. The temple area is located in front of the upper part of the ear. The pulse is felt just above a large, raised bony area called the zygomatic arch.
e. Ulnar. Like the radial pulse, the ulnar pulse is taken at the wrist. The radial pulse is taken over the artery on the thumb side of the wrist while the ulnar pulse is taken on the other side of the wrist. Both pulses are taken on the palm side of the wrist. The radial artery is normally preferred over the ulnar artery for taking the pulse because the radial artery is somewhat larger.
f. Femoral. The femoral pulse is taken in the groin area by pressing the right or left femoral artery against the ischium (the lower part of the pelvic bones located in the front part of the body).
g. Popliteal. The popliteal pulse is taken in the middle of the area located on the inside of the knee (the area opposite the kneecap).
h. Posterior Tibial. The posterior tibial pulse is taken at the top of the ankle or just above the ankle on the back, inside part of the ankle.
i. Dorsalis Pedis. The dorsalis pedis pulse is taken on the top portion of the foot just below the ankle. The pulse is taken in the middle of this area (not to the inside or outside).
j. Apical. Unlike the other sites, the apical pulse is not taken over an artery. Instead, it is taken over the heart itself. The apical pulse (actually, the heartbeat) can be felt over the apex of the heart (the pointed lower end of the heart.) This site is located to the (patient's) left of the breastbone and two to three inches above the bottom of the breastbone. The apical pulse is easily heard when a stethoscope is used.
David L. Heiserman
Publisher: SweetHaven Publishing Services
Copyright © 2006 SweetHaven Publishing Services