Critique of indirect diastolic end point. "Muffling" vs "Last" Sound

Publisher Website
Google Scholar
Abstract
The auscultatory method of indirect blood pressure measurement induces vasoreactive changes in the distal brachial artery which are relatively constant and do not interfere with the measurement indices. After the 1st sound the distal brachial diastolic pressure rises above and then returns to diastolic control levels at or about the last sound. Muffling was absent or coincided with the last sound in 37% of the measurement cycles. Muffling when present occurs at cuff pressures 12 to 20 mm Hg higher than direct diastolic end point. The last Korotkoff sound occurs 4 to 10 mm Hg above intra-arterial diastolic end point and is a clinically accurate and reliable index of diastolic pressure.