Copyright Goodheart-Willcox Co., Inc. Chapter 18 Vital Signs, Height, and Weight 467 Of these three, the radial and apical arteries are used most often. A nursing assistant may also measure pulse at the carotid and brachial arteries. The radial pulse is taken by feeling the radial artery located at the wrist (thumb side of the hand) on bare skin. Two fingers are gently placed on the radial artery to take the pulse. If a resident has an intravenous (IV) catheter in one arm, do not use that arm when taking the pulse. The apical pulse is taken by listening to the apical artery located at the apex of the heart (bottom left between the sternum and left nipple). It is usually taken if radial pulse is difficult to count or if a resident is unconscious. This pulse is taken using a stethoscope, or a medical device for listening to sounds in the body through bare skin. The carotid pulse is taken by feeling the carotid artery. It is usually taken when a resident is uncon- scious (for example, during CPR). The Stethoscope A stethoscope is used to help measure an apical pulse. It is also used when taking blood pressure, which is discussed later in this section. The stethoscope increases the sound of a pulse and transfers it to the user’s ears. A stethoscope is composed of two earpieces rubber or plastic tubing a brace, which connects the tubing to the earpieces a diaphragm, or larger, flat surface that magnifies sound and a bell on the other side, which can detect fainter sounds (Figure 18.17). Before using a stethoscope, always disinfect the earpieces, diaphragm, and bell by rubbing them lightly with antiseptic or alcohol wipes. When cleaning the earpieces with alcohol, give the alcohol time to evaporate. Alcohol can be painful in the ear canal. Wipe the tubing if it has come in contact with the resident or bed linen. Place the earpieces firmly in your ear canals. The earpieces should fit snugly and block out any outside sounds. Once the earpieces are in place, rub lightly on Earpiece Brace Diaphragm Bell Tubing Alex Hinds/Hemera/Thinkstock Figure 18.17 Illustrated here are the parts of the stethoscope. Carotid pulse Brachial pulse Radial pulse Radial pulse Apical pulse Temporal pulse Popliteal pulse (behind knee) Dorsalis pedis pulse Dorsalis pedis pulse Femoral pulse © Body Scientific International Figure 18.16 Pulse can be measured at all of the locations shown here.