Ventilation distribution in rats: Part I - The effect of gas composition as measured with electrical impedance tomography
The measurement of ventilation distribution is currently performed using inhaled tracer gases for multiple breath inhalation studies or imaging techniques to quantify spatial gas distribution. Most tracer gases used for these studies have properties different from that of air. The effect of gas density on regional ventilation distribution has not been studied. This study aimed to measure the effect of gas density on regional ventilation distribution.
Ventilation distribution was measured in seven rats using electrical impedance tomography (EIT) in supine, prone, left and right lateral positions while being mechanically ventilated with either air, heliox (30% oxygen, 70% helium) or sulfur hexafluoride (20% SF6, 20% oxygen, 60% air). The effect of gas density on regional ventilation distribution was assessed.
Gas density did not impact on regional ventilation distribution. The non-dependent lung was better ventilated in all four body positions. Gas density had no further impact on regional filling characteristics. The filling characteristics followed an anatomical pattern with the anterior and left lung showing a greater impedance change during the initial phase of the inspiration.
It was shown that gas density did not impact on convection dependent ventilation distribution in rats measured with EIT.
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- Ventilation distribution in rats: Part I - The effect of gas composition as measured with electrical impedance tomography
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BioMedical Engineering OnLine
- Online Date
- September 2012
- Online ISSN
- BioMed Central
- Additional Links
- Electrical impedance tomography
- Ventilation distribution
- Author Affiliations
- 1. Paediatric Critical Care Research Group, Paediatric Intensive Care Unit, Mater Children’s Hospital, South Brisbane, QLD, Australia
- 2. Critical Care Research Group, The Prince Charles Hospital, Brisbane, QLD, Australia
- 4. Medical Engineering, Queensland University of Technology, Brisbane, QLD, Australia
- 5. Paediatric Intensive Care Unit, Mater Children’s Hospital, South Brisbane, 4101, QLD, Australia
- 3. Centre for Advanced Imaging, The University of Queensland, Brisbane, QLD, Australia