Korotkoff sounds are produced by which physiologic phenomenon?

Korotkoff sounds are produced by which physiologic phenomenon?

• A. Turbulent blood flow
• B. Laminar blood flow
• C. Valve closure noise
• D. Vascular wall vibrations without flow

Answer: (A)

Korotkoff sounds arise when blood is forced through a partially occluded artery as the cuff pressure falls below the systolic level. The cuff compresses the brachial artery, narrowing the lumen; as the artery opens enough to allow flow, the blood becomes turbulent at the site of this temporary narrowing. This turbulence creates vibrations in the vessel wall and surrounding tissues, which are transmitted to the stethoscope as the characteristic sounds heard during blood pressure measurement. When cuff pressure drops further and flow becomes smooth again (laminar), these sounds disappear. The other options describe flow states or noises that do not produce the auscultatory sounds observed.

Korotkoff sounds arise when blood is forced through a partially occluded artery as the cuff pressure falls below the systolic level. The cuff compresses the brachial artery, narrowing the lumen; as the artery opens enough to allow flow, the blood becomes turbulent at the site of this temporary narrowing. This turbulence creates vibrations in the vessel wall and surrounding tissues, which are transmitted to the stethoscope as the characteristic sounds heard during blood pressure measurement. When cuff pressure drops further and flow becomes smooth again (laminar), these sounds disappear. The other options describe flow states or noises that do not produce the auscultatory sounds observed.