Compensated blood pressure measurement through analysis of heart sounds in a body-area-network
|Duration:||01.11.2016 - 30.11.2017|
|Project Leader:||Prof. Dr.-Ing Horst Hellbrück|
|Former Staff:||Martin Mackenberg|
Invasive pressure measuring of arterial blood pressure and central venous pressure is a standard procedure in critical neuro surgery or heart surgery. Altitude of the blood pressure sensor is the same as the reference point, which might be the right auricle with patient in supine position. Permanent changes in position of the patient during minimally invasive procedures or changes of height during radiologic interventions require permanent manual adjustment due to incorrect display of blood pressure.
As part of LUMEN II methods for adjusting the invasive blood pressure measurement with multi-sensor systems. We aim to develop methods to determine the position of the human body and the reference sensor within a Body-Area-Network (BAN). The measurement of heart sounds enables the localization of the heart by time-of-flight measurements. Furthermore, heart sounds offer information for diagnostic procedures.
The foundation for this process is a synchronized detection and recording of heart sounds in a body-area-network. Time of flight measurements provide the position of the heart which can be utilized in the compensation of the heart reference point.
|||Reflection and transmission of ultra-wideband pulses for detection of vascular pressure variation and spatial resolution within soft tissues , In Biomedical Physics & Engineering Express, volume 2, 2016. [bib] [pdf] [abstract]|
Ultra-wideband signals have a variety of applications. An upcoming medical application is the detection of the heart rate of patients. However, current UWB systems provide poor resolution and are only able to detect vessels with a large diameter, e.g. the aorta. The detection and quantification of vascular dilation of thinner vessels is essential to develop wearable ultra-wideband based devices for real-time detection of cardiovascular conditions of the extremities. The reflection and transmission processes of those signals within inhomogeneous bodies are complex and their prediction is challenging. In this paper, we present an experimental setup (UWB system; phantom) for the detection of vascular dilation within soft tissues. Furthermore, we suggest a theoretical simulation model for the prediction of the reflection of ultra-wideband pulses and compare these simulated predictions to results of measurements within the phantom. The results verify that we are able to identify vascular dilation within the simulation model and the experimental setup, depending on the depth of the vessel (20 mm, 40 mm, 60 mm).