The global respirator shortages caused by the COVID-19 pandemic highlighted the need for innovative and effective solutions for respiratory failure. Scientists have long known of the ability of aquatic species to absorb oxygen rectally, but not until recently have researchers felt the need to further study the mechanism by which this alternative gas exchange takes place.
Researchers out of Tokyo Medical University and Cincinnati Children’s Hospital Medical Center have recently published a study in journal, Med, showing that they were able to prolong the lives of rodents and pigs by delivering oxygen through their anus.
The researchers believe this may become a viable way to deliver oxygen to humans struggling to breathe, as well.
Study author Ryo Okabe said: ‘The rectum has a mesh of fine blood vessels just beneath the surface of its lining, which means that drugs administered through the anus are readily absorbed into the bloodstream. This made us wonder whether oxygen could also be delivered into the bloodstream in the same way.’
The team of scientists were able to successfully deliver oxygen to the mice and rodents through both direct rectal delivery of the oxygen in gas form, as well as rectal delivery through an oxygen-rich liquid infusion.
When placed in a lethal, low-oxygen environment, 75% of the mice were able to survive for 50 minutes when delivered oxygen rectally in gas-form. Mice that received the oxygen-rich liquid via their anus were able to walk considerably farther than those that did not, while the researchers also found an increase in the amount of oxygen reaching the animals’ hearts.
The same technique applied to pigs also resulted in the animal’s skin becoming less cold and pale, in addition to increasing their ability to walk under low oxygen conditions.
‘Artificial respiratory support plays a vital role in the clinical management of respiratory failure due to severe illnesses such as pneumonia or acute respiratory distress syndrome,’ said senior study author Takanori Takebe. ‘Although the side effects and safety need to be thoroughly evaluated in humans, our approach may offer a new paradigm to support critically ill patients with respiratory failure.’