Blood-pressure primer : the sphygmomanometer and its practical application / by Francis Ashley Faught.

  • Faught, Francis Ashley, 1881-1963.
Date:
1914
Catalogue details

Licence: Public Domain Mark

Credit: Blood-pressure primer : the sphygmomanometer and its practical application / by Francis Ashley Faught. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    To obtain diastolic reading.—Again obliterate the pulse and allow the air pressure to gradually fall through the needle-valve. As the pressure falls the needle will be seen to fluctuate in rhythm with the pulse; after a time this movement will become less and eventually disappear. The pressure indicated on the dial at that time will be the diastolic pressure. Obliterate the radial pulse, then gradually reduce the air pressure; when the pulse returns to the wrist it will at first be very feeble and thready, then it will come up full and strong under the finger. Take the reading at the moment the pulse becomes full and normal in character. This will be the diastolic pressure. The value of correctness of the ausculatory method of determining blood-pressure has, during the last few years, been conclusively demonstrated. This was first introduced by Korotokoff, of St. Petersburg, in 1905, who, instead of using the finger upon the radial pulse, substituted the stethoscope applied over the brachial artery at the bend of the elbow. On the return of the blood under the armlet, a distinct throbbing becomes audible, which gradually increases in loudness as the pressure in the cuff lessens, and then gradually dies down and disappears when the artery ceases to be obstructed at any time during the heart cycle. The chief advantage of the auscultatory or auditory method is in that it gives not only the high point— the systolic pressure—very definitely, but also the low point—or diastolic pressure, a point of great value, since it is well recognized that, under many condi- tions by the older methods, it is impossible to obtain