Blood pressure in general practice / by Percival Nicholson, M.D.; with seven illustrations.

  • Nicholson, Percival, 1881-
Date:
[1913], [©1913]
Catalogue details

Licence: Public Domain Mark

Credit: Blood pressure in general practice / by Percival Nicholson, M.D.; with seven illustrations. 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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    pulse pressure, hy the simple process of subtraction, e. g. Systolic 160 mm. Hg Diastolic 120 mm. Hg Pulse pressure 40 mm. Hg Of pulse pressure and diastolic pres- sures I shall have more to say later. Auscultation Method, on What Based. —In the auscultation method it is largely a question of the physics of fluids, e. g., the artery is constricted by means of the pneumatic cuff; below it there is no ar- terial flow, and the vessel walls are in a semi-relaxed condition. The air pressure in the cuff is lowered gradually until the heart has power enough to drive some blood into the relaxed vessel beyond. The sudden flow of blood into the relaxed vessel sends the wall into vi- bration, and a loud, clear thump is heard, which gives the systolic pressure. In making the diastolic estimation there again is a physical condition of a fully ex- panded artery above the pneumatic cuff,