Effects of Partial Gravity on the Function and Particle Handling of the Human Lung
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Purpose of Review
The challenges presented to the lung by the space environment are the effects of prolonged absence of gravity, the challenges of decompression stress associated with spacewalking, and the changes in the deposition of inhaled particulate matter.
Although there are substantial changes in the function of the lung in partial gravity, the lung is largely unaffected by sustained exposure, returning rapidly to a normal state after return to 1G. Provided there is adequate denitrogenation prior to a spacewalk, avoiding the development of venous gas emboli, the lung copes well with the low-pressure environment of the spacesuit. Particulate deposition is reduced in partial gravity, but where that deposition occurs is likely in the more peripheral airspaces, with associated longer retention times, potentially raising the toxicological potential of toxic dusts.
Despite its delicate structure, the lung performs well in partial gravity, with the greatest threat likely arising from inhaled particulate matter (extra-terrestrial dusts).
KeywordsRespiratory Aerosol transport Deposition Gas exchange
Many of the studies were funded by NASA or the National Space Bimbedical Research Institute under various contracts and grants. GK Prisk is currently funded by NIH under R01 HL119263.
Compliance with Ethical Standards
Conflict of Interest
Dr. Prisk has nothing to disclose.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major Importance
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