History
Research in the area has been progressing since the mid-1960s, when Dr. J. Kylstra from the State University of New York carried out early experiments. This was followed by further experiments by doctors Leland Clark and Golan, reported in the journal Science (June 24, 1966), in which mice had survived for up to 20 hours, though only by inducing hypothermia in the animals.
Since 1990, experiments leading to clinical trials in human cases have been funded by Alliance Pharmaceutical Corp, using perfluorooctyl bromide (or perflubron) under the brand name LiquiVent.
Advantages and Problems
The advantages of liquid breathing are that the liquid is not forced into the lungs under high pressure like air, but can flow at low pressure. It is also able to pass oxygen into the lung's alveoli much more efficiently than air, both because the perflourocarbon carry much more oxygen in a given volume, and because the alveoli are able to float in the liquid so that the full surface area of the lungs is used.
Problems that have had to be overcome are removing the exhaled carbon dioxide, and damage caused by the breathing medium to the surface of the lungs.
Other potential uses in the long term could be in diving, where breathing liquid would overcome the problems of pressure, especially in avoiding the dangers of decompression sickness ("the bends"). As supposed in the 1989 science-fiction film The Abyss.Uses
The immediate use of liquid breathing is likely to be in the treatment of premature babies and adults with severe lung damage, perhaps resulting from fires.