Until recently, arterial blood pressure in the digit has been measured chiefly by the "flush-throb,"1-4 plethysmographic,5 or oscillometric6,7 methods. In 1958, Gaskell and Krisman8 introduced a technique with which Korotkow sounds in the digital arteries could be heard by direct auscultation. This method, as far as systolic blood pressures is concerned, is well correlated with plethysmographic techniques and with direct observation of blood flow in the nail-bed capillaries. Korotkow sounds can also be detected by a condenser microphone and visualized on an oscilloscope * or amplified electronically and heard by ear, using a speaker. A comparison of the "flush-throb," direct auscultation, and electronic microphone techniques was undertaken by measuring digital arterial blood pressure with several combinations of two methods simultaneously.
All determinations were made with the patient at rest and the hand supported at heart level. Three to six readings were made in each patient. One
WEINREB HL, NAFTCHI N, MENDLOWITZ M. The Measurement of Digital Arterial Blood PressureA Comparison of the "Flush-Throb," Direct Auscultation, and Electronic Microphone Techniques. AMA Arch Surg. 1960;80(1):131-134. doi:10.1001/archsurg.1960.01290180133016