Is the Era of "Butt Breathing" Coming?... "May Serve as an Alternative or Supplement to Ventilators"

Injection of Oxygen-Carrying Liquid into the Rectum Confirms Safety
Next Step: Verifying Actual Oxygen Delivery Effect

The actual medical applicability of the so-called "butt breathing" theory, which drew attention after winning the Ig Nobel Prize last year, has now been confirmed. The Ig Nobel Prize, a parody of the Nobel Prize, is announced every October by the American humor science magazine "Annals of Improbable Research" at Harvard University. It is awarded to unconventional or ingenious research that breaks the mold of traditional science.

According to international media outlets such as the New York Post, a joint research team from Japan and the United States has confirmed the safety of "enteral ventilation," a technique that supplies oxygen through the rectum for patients who have difficulty breathing normally due to reduced lung function, in its first human clinical trial.

The researchers focused on the survival strategies of certain animals-such as fish, turtles, sea cucumbers, and pigs-that absorb oxygen through the anus or intestinal mucosa in oxygen-deficient environments. Drawing on this, they devised a method in which oxygen-rich liquid is injected into the rectum when the lungs are not functioning properly, allowing oxygen to be delivered to the bloodstream through the intestinal wall.

The first human trial involved 27 healthy Japanese men. The researchers administered perfluorodecalin, a liquid with high oxygen-carrying capacity, into the rectum in a manner similar to an enema and maintained it for 60 minutes. Since the purpose of this experiment was to confirm safety, the liquid used did not contain oxygen.

As a result, 20 participants completed the experiment, tolerating up to 1.5 liters, and while some reported a feeling of bloating and discomfort, no serious side effects were observed.

Dr. Takanori Takebe, who led the research, stated, "This trial was a step to confirm whether the procedure is safe for humans, and the oxygen delivery effect has not yet been verified." He added, "The next step will be to use a liquid that actually contains oxygen to evaluate whether it can improve blood oxygen levels."

The research team further explained, "In the future, this technology is expected to serve as an alternative or supplementary means to ventilators for patients who have difficulty receiving oxygen due to airway injury, pneumonia, or severe respiratory failure."

This technology was first made public in a 2021 cover article in Med, based on initial studies conducted on pigs, and in 2024, it was awarded the Ig Nobel Prize in Physiology.