Noninvasive measurement of beat-to-beat arterial blood pressure by the Korotkoff sound delay time

Abstract

The beat-to-beat blood pressure estimated by KDT provides an accurate estimate of MAP in the preliminary experiments and represents a potential acceptable alternative to invasive blood pressure monitoring during laboratory studies.

A pilot application of Korotkoff sound delay time in evaluating cardiovascular status

“…The experimental system is similar to that in [9] It includes four units: i) an analog circuit unit to condition the cuff pressure, oscillometric pulse, Korotkoff sounds and invasive blood pressure (IBP); ii) a microprocessor (C8051F060) to receive the analog signals and send them to the computer; iii) a set of automatic inflating and deflating appliance controlled by the microprocessor to realize the linear deflation of the cuff; iv) a personal computer with self-programmed data acquiring and analyzing software [9].…”

“…2, the Korotkoff sound delay time for the four cardiac cycles at different cuff pressure demonstrate that T1 at is the longest while T4 is the shortest. In a series of the KDTs of the whole measurement in cuff deflation, the KDT corresponding to the first Korotkoff sound is the longest, while the KDTs corresponding to the subsequent Korotkoff sound become shorter and shorter respectively, and the shortest one appears at the last Korotkoff sound [9].…”

“…The pro- cess of the experiment was the same with that in [9]. The cuff pressure, oscillometric pulse and Korotkoff sounds were collected on the subject's right upper arm.…”

“…The relationship coefficient between KDT and invasive blood pressure was calculated. Moreover, a method to estimate the beat-to-beat mean arterial pressure by Korotkoff sound delay time has been proposed in [9].…”