Comparison of Flow Estimators for Rotary Blood Pumps: An In Vitro and In Vivo Study
OPEN ACCESS
Loading...
Author / Producer
Date
2018-12-15
Publication Type
Journal Article
ETH Bibliography
yes
Citations
Altmetric
OPEN ACCESS
Data
Rights / License
Abstract
Various approaches for estimating the flow rate of a rotary blood pump have been proposed for monitoring and control purposes. They have been evaluated under different test conditions and, therefore, a direct comparison among them is difficult. Furthermore, a limited performance has been reported for the areas where the pump flow and motor current present a non-monotonic relationship. In this regard, we selected most approaches that have been presented in literature and added a modified one, resulting in four estimators, which are either non-invasive or invasive, i.e., inlet and outlet pump pressure sensors are used. Data from in vitro and in vivo studies with the Deltastream pump DP2 were used to compare the estimators under the same test conditions. These data included both constant and varying pre- and afterload, contractility, viscosity, as well as pump speed settings. Bland–Altman plots were used to evaluate the performance of the estimators. The mean error of the overall estimated flow in vitro ranged from 0.002 to 0.38 L/min and the limits of agreement (LoA) between ± 2 L/min. During negative flows the mean error decreased by about 25% when the pump inlet pressure was added as an input. In vivo, the mean errors increased, while the LoA remained in the same range. An estimator based on pump pressure difference improves the reliability in areas where flow and current relationship is not monotonic. A trade-off between estimation accuracy and number of sensors was identified. The estimation objective and the potential errors should be considered when selecting an estimation approach and designing the pump systems.
Permanent link
Publication status
published
External links
Editor
Book title
Journal / series
Volume
46 (12)
Pages / Article No.
2123 - 2134
Publisher
Springer
Event
Edition / version
Methods
Software
Geographic location
Date collected
Date created
Subject
Ventricular assist device; Numerical model of cardiovascular system; Physiological control; Monitoring; Extended Kalman filter; Pressure sensor
Organisational unit
03943 - Meboldt, Mirko / Meboldt, Mirko
Notes
It was possible to publish this article open access thanks to a Swiss National Licence with the publisher.
Funding
Related publications and datasets
Is referenced by: