Breathing From Behind
COVID-nineteen highlighted our dependence on ventilators to keep the very sick breathing, but there is a downside. While they save lives, they can also damage lungs because of the high pressure used to get air inside. Do we have a better option? Maybe.
Nature shows us alternate ways fish and arthropods get oxygen; They can actually breathe through their guts. The human colon is also a remarkable organ whose primary purpose is to remove water and salts from digested food and create "solid" waste for exiting. But scientists have been exploring whether oxygen introduced into the colon could sustain life.
In studies with mice, those given low oxygen air survived eighteen minutes, but those getting gaseous oxygen directly to their colons lived up to fifty minutes. Next they tried using an oxygen carrying liquid called perfluorocarbon to deliver the oxygen. It's already being used in premature infants and adults to supply oxygen to the lungs and directly into blood vessels.
Mice in a low oxygen chamber receiving perfluorocarbon through the rectum fared much better than mice receiving just saline. In pigs with respiratory failure, those given enemas with oxygenated perfluorocarbon lived for extended times. And they had no obvious side effects.
This "breathing from behind" may be a game changer one day for many of us with lung injuries or who get critically ill avoid ventilators for something a bit gentler.
More Information
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