Demand flow system with two controlled valves for support of spontaneous breathing during high-frequency oscillatory ventilation

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21230%2F18%3A00326081" target="_blank" >RIV/68407700:21230/18:00326081 - isvavai.cz</a>

Alternative codes found

RIV/68407700:21460/18:00326081

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Demand flow system with two controlled valves for support of spontaneous breathing during high-frequency oscillatory ventilation

Original language description

High-frequency oscillatory ventilation (HFOV) is a debated mode of mechanical ventilation of adult patients suffering from Acute Respiratory Distress Syndrome (ARDS). The Demand Flow System (DFS) has been developed for support of spontaneous breathing during HFOV. The DFS compensates for the pressure changes in a ventilator circuit of a high-frequency oscillatory ventilator 3100B caused by spontaneous breathing and reduces imposed breathing effort of a patient. The aim of this work was to develop the DFS for support of spontaneous breathing during HFOV with two controlled valves, inspiratory and expiratory, to optimize the DFS with respect to the reduction of a patient’s breathing effort, and to evaluate the effectiveness of versions of the DFS for support of spontaneous breathing during HFOV. A system was designed with the control valves placed independently of the HFO ventilator bias flow, allowing to separate HFOV from the action of the DFS. For the new version of the DFS, a control algorithm was implemented, based on a combination of a proportional-summation-difference controller and a filter of high-frequency (HF) oscillations. Results of animal experiments show that complete filtration of HF oscillations from measured pressure signal is essential for proper functioning of the DFS with two control valves. Filtration of HF oscillations limits the ability of a controller to compensate for the pressure changes when compared to conventional ventilators; however, it prevents vibrations of the DFS valves and assures that the DFS does not interfere with HFOV and related gas exchange. The new version of DFS reduces imposed breathing effort during HFOV better by 11% on average than a previous version of the DFS with one controlled valve and a linear-quadratic Gaussian controller. Results of this work might help to allow successful weaning from HFOV to extubation.

Czech name

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Czech description

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Type

O - Miscellaneous

CEP classification

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OECD FORD branch

20601 - Medical engineering

Project

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Continuities

S - Specificky vyzkum na vysokych skolach

Publication year

2018

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů