Related Experiment Videos
Fluid Exchange in the isolated perfused lung
Annals of the New York Academy of Sciences
|January 1, 1982
Summary
This study shows that isolated rabbit lungs mimic in situ lung fluid exchange. Fluid reabsorption occurs at the air-blood barrier, not in perivascular spaces, offering insights into lung physiology.
Area of Science:
- Pulmonary Physiology
- Cardiovascular Physiology
- Fluid Dynamics
Background:
- Understanding transvascular fluid shifts in the lungs is crucial for managing pulmonary edema.
- Previous studies on isolated lung preparations yielded varied results regarding vascular permeability.
Purpose of the Study:
- To evaluate the isolated, perfused rabbit lung as a model for studying transvascular fluid shifts.
- To determine the factors influencing fluid filtration and reabsorption in the lung.
Main Methods:
- Utilized an isolated, perfused rabbit lung preparation.
- Measured filtration coefficients using plasma and Krebs-Ringer dextran T 70 perfusates.
- Assessed interstitial fluid pressure in response to changes in alveolar and pleural pressures.
- Observed fluid reabsorption dynamics.
Main Results:
- The isolated lung preparation accurately reflects in situ lung vascular permeability.
- Filtration coefficient remained consistent regardless of perfusate composition (plasma vs. dextran).
- Increased alveolar pressure reduced fluid filtration; increased lung volume reduced extravascular resistance and perivascular space pressure.
- Fluid reabsorption was observed, localized to the thicker regions of the air-blood barrier.
Conclusions:
- The isolated, perfused rabbit lung is a valid model for studying pulmonary fluid exchange.
- Lung fluid dynamics are influenced by alveolar pressure and lung volume.
- Fluid reabsorption likely occurs at the thick air-blood barrier due to higher interstitial fluid pressure.