Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Variable expiration control for an intensive care ventilator
Linköping University, Department of Biomedical Engineering.
Linköping University, Department of Biomedical Engineering.
2019 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

Critical care patients are often connected to ventilators, to support or replace their breathing. The ventilators deliver a mixture of gas to the patient by applying a specific volume or pressure, and then the patient exhales passively. This thesis is based of the hypothesis that a slower reduction of the expiration pressure could benefit intensive care patients connected to a ventilator. To enable research within the area, a device which can control the expiration is needed.

In this thesis project, an expiration valve was controlled to create different pressure patterns during expiration. To facilitate the research and the usage of the expiration control, an application software was created with the purpose to simulate relevant pressure, flow and volume curves.

The prototype is an expiration cassette created for the ventilator Servo-i by Maquet Getinge Group. To enable flexibility, the prototype is external and no information is transmitted from or to the ventilator. The prototype has its own flow and pressure sensors. The different pressure patterns which the prototype uses are designed as a linear decrease and as if a constant resistance was added to the system. The user can also create their own pressure pattern, by deciding 20 pressure points in the duration of two seconds. The simulation application was designed with the ability to simulate the same pressure patterns available with the prototype. By using a lung model, it is possible to simulate the ideal pressure, flow and volume in the lungs which can be expected from the chosen expiration control. During the implementation, two different types of lung models were evaluated in order to determine the specificity required.

The prototype was tested with settings which were chosen to challenge the performance of the control. Some problematic areas were detected, such as high pressures or large volumes. However, the prototype was judged to perform well enough to be used in animal trials. The lung model used for the simulation application was a simple model of the lung, consisting of a resistor and a capacitor in series. The simulations were compared with the real system with the purpose to get an indication on the difference between theory and reality. The application presents the expected behavior when using the expiration control. However, it should be kept in mind by the user that the application represents a theoretical model.

Place, publisher, year, edition, pages
2019. , p. 84
Keywords [en]
mechanical ventilation, lung collapse, expiration control
National Category
Medical Engineering
Identifiers
URN: urn:nbn:se:liu:diva-157761ISRN: LIU-IMT-TFK-A--19/564--SEOAI: oai:DiVA.org:liu-157761DiVA, id: diva2:1328057
External cooperation
Maquet Critical Care
Subject / course
Medical Technology
Presentation
2019-06-11, IMT1, Linköping, 10:15 (Swedish)
Supervisors
Examiners
Available from: 2019-06-24 Created: 2019-06-20 Last updated: 2019-06-24Bibliographically approved

Open Access in DiVA

fulltext(5841 kB)64 downloads
File information
File name FULLTEXT01.pdfFile size 5841 kBChecksum SHA-512
07ea9e06effac897340920d285b73255b90909688491033054c7ffdb9cf43d8de96d1fee92da282a8494f9a7af2e35067558c7667d11bb6c3d720f449a63bcf5
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Kilander, JohannaFrisell, Madeleine
By organisation
Department of Biomedical Engineering
Medical Engineering

Search outside of DiVA

GoogleGoogle Scholar
Total: 64 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 59 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf