[abstract] MINIMUM <DELTA>P FOR BUBBLE FORMATION IN PULMONARY VASCULATURE.

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[abstract] MINIMUM <DELTA>P FOR BUBBLE FORMATION IN PULMONARY VASCULATURE.

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dc.contributor.author Sass, DJ
dc.date.accessioned 2007-12-27
dc.date.available 2007-12-27
dc.date.issued 1976
dc.identifier.uri http://archive.rubicon-foundation.org/5257
dc.description Abstract of the Undersea and Hyperbaric Medical Society, Inc. Annual Scientific Meeting held May 12-13, 1976. Carillon Hotel, Miami Beach, FL (http:www.uhms.org) en
dc.description.abstract Intravenous injection of FC 80 liquid fluorocarbon causes a gas-blood phase separation in the pulmonary capillaries. The gas pressure in the initial bubble equals atmospheric + FC 80 vapor pressure (55 mmHg; 37°C). Theoretically, bubbles should form only in uppermost lung regions where total blood gas tension is capillary blood pressure + pressure due to surface forces at the gas-liquid interface. Lung regions with bubbles can be found by comparing the spatial distributions of pulmonary blood flow (SDPBF) before and after bubbles form. The minimum overpressure (<delta>P = gas -liq. pressure) necessary for bubble formation can be estimated with measurements of regional intrathoracic pressures. Six anesthetized dogs were positioned left lateral decubitus. Saline-filled catheters were introduced percutaneously and positioned, with aide of thoracic bi-plane X-ray films, in the right atrium, thoracic aorta, pulmonary artery, and esophagus for recording pressures, and into the right ventricular outflow tract for injections. Differentially labeled radioactive microspheres (15 ± 5m) were injected before and 30 min. after bolus injection of 0.1 ml/Kg FC 80. Three dogs were then immediately rolled to right lateral decubitus and a third microsphere injection was made. The lungs were resected, dried in air while inflated with constant tracheal pressure (40 cm H0), and embedded in pour-in-place-foam. SDPBF was determined for each injection at > 2500 locations in a three-dimensional grid throughout the entire lung. After bubbles formed, the fractional distribution of cardiac output changed. There was a 41.7% decrease in the right, uppermost, lung and a 9.2% decrease in lung ventral to the trachea. Flow was unmeasureable in extreme apical and diaphragmatic sections. The results indicate that <delta>P's of only 5-10 mmHg cause bubbles to evolve in blood. Thus, small <delta>P's can cause gas embolism in divers. en
dc.description.sponsorship US NAVY en
dc.format.extent 259 bytes
dc.format.mimetype text/plain
dc.language.iso en en
dc.publisher Undersea and Hyperbaric Medical Society, Inc. en
dc.subject Decompression en
dc.subject gas embolism en
dc.subject fluorocarbon en
dc.subject pulmonary en
dc.subject bubble en
dc.subject pulmonary blood flow en
dc.subject animal en
dc.subject dog en
dc.title [abstract] MINIMUM <DELTA>P FOR BUBBLE FORMATION IN PULMONARY VASCULATURE. en
dc.type Other en

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  • UHMS Meeting Abstracts
    This is a collection of the published abstracts from the Undersea and Hyperbaric Medical Society (UHMS) annual meetings.

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