Size distribution of intravascular air emboli produced by decompression

Intravascular bubbles formed by decompression have been measured in 7 living dogs to give 14 different determinations of size distribution. Larger bubbles were estimated by the terminal rise velocity technique using the Stokes equation, while smaller bubbles were determined simultaneously, using the Coulter counter. Bubble diameters of 19--700 micrometers were recorded, these reaching the venous sinus as showers of several hundred whose mean size tended to increase with post-decompression time. Average diameters were rather smaller than previously recorded from autopsy. The results are discussed as indicating that all venous bubbles were within a size range where they would be filtered out by the lungs unless this organ had been insulated.