LESSON XXIV 

 THE CIRCULATION (Continued) 



THE INDIRECT METHOD OF MEASURING BLOOD-PRESSURE. 

 OF POSTURE AND EXERCISE 



EFFECT 



1. The Application of the Sphygmomanometer. Place the index- 

 finger of your left hand upon the skin over the brachial artery of the 

 subject. Palpate the radial pulse with the index- and middle fingers 

 of your right hand. Gently compress the brachial artery until the 

 radial pulse can no longer be felt. 



Place the index-finger of your left hand upon the skin over the 

 brachial artery. With- your right hand adjust the chest-piece of a 



FIG. 81. RiVA-Rocci's SPHYGMOMAXOMETER, EARLY TYPE. (From Janeway's "Clinical 



Study of Blood-pressure.") 



stethoscope upon the flexor surface of the elbow-joint. Do you hear a 

 sound? Gently compress the brachial artery. Describe the character 

 of the sound now heard. Explain its cause. 



The sphygmomanometer most commonly used in making these tests 

 consists of (a) a mercury manometer, (6) a narrow rubber cuff to fit 

 around the arm, and (c) an inflating bulb with exhaust valve. In the 

 sphygmotonometer the place of the mercurial indicator is taken by a steel 



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