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Analysis of novel geometry-independent method for dialysis access pressure-flow monitoring

BACKGROUND: End-stage renal disease (ESRD) confers a large health-care burden for the United States, and the morbidity associated with vascular access failure has stimulated research into detection of vascular access stenosis and low flow prior to thrombosis. We present data investigating the possib...

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Autores principales: Weitzel, William F, Cotant, Casey L, Wen, Zhijie, Biswas, Rohan, Patel, Prashant, Panduranga, Harsha, Gianchandani, Yogesh B, Rubin, Jonathan M
Formato: Texto
Lenguaje:English
Publicado: BioMed Central 2008
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2586012/
https://www.ncbi.nlm.nih.gov/pubmed/18986548
http://dx.doi.org/10.1186/1742-4682-5-22
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author Weitzel, William F
Cotant, Casey L
Wen, Zhijie
Biswas, Rohan
Patel, Prashant
Panduranga, Harsha
Gianchandani, Yogesh B
Rubin, Jonathan M
author_facet Weitzel, William F
Cotant, Casey L
Wen, Zhijie
Biswas, Rohan
Patel, Prashant
Panduranga, Harsha
Gianchandani, Yogesh B
Rubin, Jonathan M
author_sort Weitzel, William F
collection PubMed
description BACKGROUND: End-stage renal disease (ESRD) confers a large health-care burden for the United States, and the morbidity associated with vascular access failure has stimulated research into detection of vascular access stenosis and low flow prior to thrombosis. We present data investigating the possibility of using differential pressure (ΔP) monitoring to estimate access flow (Q) for dialysis access monitoring, with the goal of utilizing micro-electro-mechanical systems (MEMS) pressure sensors integrated within the shaft of dialysis needles. METHODS: A model of the arteriovenous graft fluid circuit was used to study the relationship between Q and the ΔP between two dialysis needles placed 2.5–20.0 cm apart. Tubing was varied to simulate grafts with inner diameters of 4.76–7.95 mm. Data were compared with values from two steady-flow models. These results, and those from computational fluid dynamics (CFD) modeling of ΔP as a function of needle position, were used to devise and test a method of estimating Q using ΔP and variable dialysis pump speeds (variable flow) that diminishes dependence on geometric factors and fluid characteristics. RESULTS: In the fluid circuit model, ΔP increased with increasing volume flow rate and with increasing needle-separation distance. A nonlinear model closely predicts this ΔP-Q relationship (R(2 )> 0.98) for all graft diameters and needle-separation distances tested. CFD modeling suggested turbulent needle effects are greatest within 1 cm of the needle tip. Utilizing linear, quadratic and combined variable flow algorithms, dialysis access flow was estimated using geometry-independent models and an experimental dialysis system with the pressure sensors separated from the dialysis needle tip by distances ranging from 1 to 5 cm. Real-time ΔP waveform data were also observed during the mock dialysis treatment, which may be useful in detecting low or reversed flow within the access. CONCLUSION: With further experimentation and needle design, this geometry-independent approach may prove to be a useful access flow monitoring method.
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spelling pubmed-25860122008-11-24 Analysis of novel geometry-independent method for dialysis access pressure-flow monitoring Weitzel, William F Cotant, Casey L Wen, Zhijie Biswas, Rohan Patel, Prashant Panduranga, Harsha Gianchandani, Yogesh B Rubin, Jonathan M Theor Biol Med Model Research BACKGROUND: End-stage renal disease (ESRD) confers a large health-care burden for the United States, and the morbidity associated with vascular access failure has stimulated research into detection of vascular access stenosis and low flow prior to thrombosis. We present data investigating the possibility of using differential pressure (ΔP) monitoring to estimate access flow (Q) for dialysis access monitoring, with the goal of utilizing micro-electro-mechanical systems (MEMS) pressure sensors integrated within the shaft of dialysis needles. METHODS: A model of the arteriovenous graft fluid circuit was used to study the relationship between Q and the ΔP between two dialysis needles placed 2.5–20.0 cm apart. Tubing was varied to simulate grafts with inner diameters of 4.76–7.95 mm. Data were compared with values from two steady-flow models. These results, and those from computational fluid dynamics (CFD) modeling of ΔP as a function of needle position, were used to devise and test a method of estimating Q using ΔP and variable dialysis pump speeds (variable flow) that diminishes dependence on geometric factors and fluid characteristics. RESULTS: In the fluid circuit model, ΔP increased with increasing volume flow rate and with increasing needle-separation distance. A nonlinear model closely predicts this ΔP-Q relationship (R(2 )> 0.98) for all graft diameters and needle-separation distances tested. CFD modeling suggested turbulent needle effects are greatest within 1 cm of the needle tip. Utilizing linear, quadratic and combined variable flow algorithms, dialysis access flow was estimated using geometry-independent models and an experimental dialysis system with the pressure sensors separated from the dialysis needle tip by distances ranging from 1 to 5 cm. Real-time ΔP waveform data were also observed during the mock dialysis treatment, which may be useful in detecting low or reversed flow within the access. CONCLUSION: With further experimentation and needle design, this geometry-independent approach may prove to be a useful access flow monitoring method. BioMed Central 2008-11-05 /pmc/articles/PMC2586012/ /pubmed/18986548 http://dx.doi.org/10.1186/1742-4682-5-22 Text en Copyright © 2008 Weitzel et al; licensee BioMed Central Ltd. http://creativecommons.org/licenses/by/2.0 This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( (http://creativecommons.org/licenses/by/2.0) ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Research
Weitzel, William F
Cotant, Casey L
Wen, Zhijie
Biswas, Rohan
Patel, Prashant
Panduranga, Harsha
Gianchandani, Yogesh B
Rubin, Jonathan M
Analysis of novel geometry-independent method for dialysis access pressure-flow monitoring
title Analysis of novel geometry-independent method for dialysis access pressure-flow monitoring
title_full Analysis of novel geometry-independent method for dialysis access pressure-flow monitoring
title_fullStr Analysis of novel geometry-independent method for dialysis access pressure-flow monitoring
title_full_unstemmed Analysis of novel geometry-independent method for dialysis access pressure-flow monitoring
title_short Analysis of novel geometry-independent method for dialysis access pressure-flow monitoring
title_sort analysis of novel geometry-independent method for dialysis access pressure-flow monitoring
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2586012/
https://www.ncbi.nlm.nih.gov/pubmed/18986548
http://dx.doi.org/10.1186/1742-4682-5-22
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