| dc.contributor.author | Alvarez, Enrique | |
| dc.description.abstract | This document is a paper-based dissertation. The dissertation is a collection of articles
written by the author in the pursuit to develop a novel method to measure blood pressure (BP).
The introduction chapter describes how the documents are interrelated. This work starts with the
description of the development and design of a non-invasive medical device capable of
measuring arterial BP with a combination of inflationary and deflationary procedures. In addition
to the device, we conducted a human-based study to characterize the properties of the BP signal
in the inflationary and deflationary curves. With the signals acquired, we focused on the
uncertainty occurring when taking two consecutive BP measurements.
The prototype was composed of 1) a modified off-the-shelf oscillometric BP system, 2) a
contact microphone with an amplifier, and 3) a high-sensitivity pulse oximeter, and its control
electronics. The device captured the cuff pressure signal, arterial skin-surface acoustics, and
photoplethysmography (PPG).
The captured signals were processed and analyzed. We focused our analysis on the
characterization of the uncertainty of two consecutive BP measurements by studying the biosignals
captured with the custom-made apparatus.
Accurate non-invasive BP measurements are vital in preventing and treating many
cardiovascular diseases. The “gold standard” for non-invasive procedures is the auscultatory
method, which is based on detecting Korotkoff sounds while deflating an arm cuff. Using this
method as a “gold standard” requires highly-trained technicians and has an intrinsic uncertainty
in its BP predictions. In this document, we analyze and characterize the origins of BP
uncertainty.
By analyzing the captured bio signals we postulate an uncertainty model for two
consecutive BP measurements. Our research group developed a computer-based simulation of
auscultatory BP measurement uncertainty, and these modeled results were compared to a humansubject
experiment with a group of 20 diverse-conditioned individuals.
Uncertainties were categorized and quantified. The total computer-simulated uncertainty
ranged between -8.4 mmHg to 8.4 mmHg in systolic BP and -8.4 mmHg to 8.3 mmHg in
diastolic BP at a 95% confidence interval. The limits in the human-based study ranged from -8.3
mmHg to 8.3 mmHg in systolic BP and -16.7 mmHg to 4.2 mmHg in diastolic BP. | en_US |
| dc.publisher | North Dakota State University | en_US |
| dc.rights | NDSU policy 190.6.2 | en_US |
| dc.title | Characterization of Inflationary and Deflationary Auscultatory Blood Pressure Measurements | en_US |
| dc.type | Dissertation | en_US |
| dc.date.accessioned | 2023-12-07T17:03:09Z | |
| dc.date.available | 2023-12-07T17:03:09Z | |
| dc.date.issued | 2022 | |
| dc.identifier.uri | https://hdl.handle.net/10365/33292 | |
| dc.subject | auscultatory | en_US |
| dc.subject | blood pressure | en_US |
| dc.subject | Korotkoff | en_US |
| dc.rights.uri | https://www.ndsu.edu/fileadmin/policy/190.pdf | en_US |
| ndsu.degree | Doctor of Philosophy (PhD) | en_US |
| ndsu.college | Engineering | en_US |
| ndsu.department | Electrical and Computer Engineering | en_US |
| ndsu.program | Electrical and Computer Engineering | en_US |
| ndsu.advisor | Ewert, Dan | |
