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Oleic Acid-Injection in Pigs As a Model for Acute Respiratory Distress Syndrome
Published on: October 26, 2018
EITS changes following oleic acid induced lung water
B H Brown1, R Flewelling, H Griffiths
1Department of Medical Physics, Royal Hallamshire Hospital, Sheffield, UK.
Physiological Measurement
|November 1, 1996
Summary
Electrical impedance tomographic spectroscopy (EITS) effectively monitors lung water changes. This technique shows frequency-dependent impedance changes correlating with lung edema, validated in animal models.
Area of Science:
- Medical Imaging
- Physiology
- Biophysics
Background:
- Pulmonary edema is a critical condition.
- Accurate monitoring of lung water is essential for patient management.
- Electrical impedance tomography (EIT) offers a non-invasive imaging approach.
Purpose of the Study:
- To evaluate electrical impedance tomographic spectroscopy (EITS) for quantifying lung water changes.
- To investigate the frequency-dependent behavior of lung impedance during edema.
- To model these changes using the Cole equation.
Main Methods:
- EITS measurements were performed on three goats before and after oleic acid injection.
- Lung water was concurrently measured using a double-indicator technique.
- Ex vivo porcine lungs were used for four-electrode impedance measurements and Cole equation modeling.
Main Results:
- Significant decreases in lung electrical impedance were observed with increased lung water.
- The magnitude of impedance change was frequency-dependent.
- Cole equation modeling successfully described the observed impedance spectra.
- Results from in vivo and ex vivo experiments showed similar trends.
Conclusions:
- EITS is a viable method for tracking acute lung water changes.
- Frequency-dependent impedance analysis provides insights into lung edema.
- The Cole equation effectively models EITS data in pulmonary edema scenarios.
