Determination of alveolar surface area and tension from in situ pressure-volume data.

Details

• Personal Author:
  Fisher MJ ; Weber KC ; Wilson MF
• Description:
  Alveolar surface area and tension were determined in-situ from gas and liquid pressure/volume (PV) curves. Cats were anesthetized and placed with chest open inside a plethysmograph. A spirometer measured volume displacement of 100 percent oxygen gas from the plethysmograph due to lung volume changes. A differential pressure transducer measured transpulmonary pressure for both air and liquid experiments. Gas flows from the lung were varied from 2.9 to 6.0 milliliters (ml) per second, and liquid flows of Ringer Locke solution were varied from 0.5 to 5.0ml per second. A proportionality constant (K) was determined by comparing the gas and liquid inflation curves at maximal lung volumes. A surface tension of 50 dynes per centimeter at large lung volumes was assumed. In the experiments in which gas and liquid flows were varied, no significant change in either the shape or the hysteresis of the PV curve was found, except when the gas flow was reduced to 1ml per second or less. At a functional residual capacity of 90ml, the alveolar surface area per kilogram of body mass was about 1.05 square meters. The volume at which the surface tension reached its maximum ranged from 255 to 175ml in eight cases. At small lung volumes, the surface tension approached zero and was always lower during deflation than during inflation for any particular volume. The mean value for (K) in eight experiments was about 1225. The authors conclude that the pressure difference between the gas and liquid curves is a major determinant of the value for surface tension. Decreasing the surface tension reduces the energy needed to inflate the lung and the tendency for transudation of fluid from the pulmonary capillaries to the alveoli. [Description provided by NIOSH]
• Subjects:
  Anesthesia Animals Lung Occupational Diseases Occupational Health Respiratory System Safety
• Keywords:
  Alveolar Cells Anesthesiology Animal Studies Author Keywords: Alveolar Air-liquid Interface Lung Function Lung Pressure-volume Curves Occupational Diseases Physiological Measurements Physiological Response Physiological Testing Respiratory Gas Transport Surface Tension Surfactant

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• ISSN:
  0034-5687
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  ALFORD - Appalachian Laboratory for Occupational Respiratory Disease
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  159-171
• Volume:
  10
• Issue:
  2
• NIOSHTIC Number:
  nn:00131140
• Citation:
  Respir Physiol 1970 Sep; 10(2):159-171
• Federal Fiscal Year:
  1970
• Peer Reviewed:
  True
• Source Full Name:
  Respiration Physiology
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:4b22a1cce75927aaee946f19d4509dcf66be065cba5749257bd4dd3725cbe7ea07513cfca7976e302439a5d981b746507f8d791df74a5649ee92e6f4678b2349
• Download URL:
  https://stacks.cdc.gov/view/cdc/184626/cdc_184626_DS1.pdf
• File Type:
  [PDF - 4.73 MB ]