Scientists Inject Microbubbles Of Oxygen Into The Bloodstream In Potential Medical Breakthrough

Humans need a cup of oxygen per minute to survive. This is because oxygen in the blood helps with energy production. In healthy individuals, oxygen is available in abundance. However, some illnesses (such as COVID-19) and acute lung trauma can cause lung damage that can compromise oxygen delivery. In turn, this can cause patients to get hypoxemia – where less oxygen makes it to the bloodstream. Even a few minutes of oxygen deprivation at the tissue level – hypoxia – can cause previously healthy people to become neurologically impacted for life.

In serious cases, patients will often be put on ventilators or be given Extracorporeal Membrane Oxygenation (ECMO) – where the blood is taken outside of the body, oxygen is added, and carbon dioxide is removed. But as seen during the COVID-19 pandemic, these machines can be scarce and can produce injuries to the lungs and cause infections.

Now, scientists at Boston Children’s Hospital might have developed an alternative way to administer oxygen to a patient: Through an intravenous line. They have published their findings in the journal PNAS.

​

Normally, if you inject oxygen into the bloodstream, it can make an air bubble that can block the blood vessel. This can often be fatal – and is what happens when divers get "the bends" after coming back to the surface too quickly after diving – but the new technology can overcome this.

The scientists showed that combining oxygen and a liquid solution containing phospholipids through a series of decreasing-sized nozzles can create bubbles that are smaller than red blood cells. This procedure can be done in real-time and on-demand.

The bubbles are coated in a “membrane” that is similar to the cells in the body. This membrane helps to prevent the bubbles from merging to create a larger one, minimizes material-related toxicities, and provides a pathway for oxygen to diffuse in and out of the blood.

In the study, when the donated human blood underwent this technology, blood oxygen saturation levels were lifted from 15 percent to over 95 percent, in just a few minutes. When the scientists conducted this study on live rats, the process increased the saturation from 20 percent to 50 percent.

Positively, these devices provide control of the volume of fluid administrated and the oxygen dosage. These parameters are both critical in disease management for critically ill patients.

Caution should be taken, however, as this was only a proof-of-concept study, which now needs to be tested on larger animals before moving on to human trials.

But looking forward, the new technology could help prepare the body for ventilators or ECMO and could also be integrated into existing ventilators, which will allow smooth integration into existing workflows.

Source