Source: “Oxygen Gas–Filled Microparticles Provide Intravenous Oxygen Delivery”

John Kheir et al.

Science Translational Medicine 4(140)

Results: Researchers at Boston Children’s Hospital found a way to get oxygen into a body even when the lungs have stopped working: by intravenously injecting gas-filled microparticles. In anesthetized rabbits with blocked windpipes, the microspheres oxygenated the body and prevented major injury to organs for 15 minutes.

Why it matters: Doctors and paramedics may eventually be able to use such injections to keep patients alive until ­longer-term methods can be employed in the hospital. Common emergency measures such as CPR and ventilators don’t work if the lungs are too damaged or the airway is blocked. Heart-lung bypass machines—which oxygenate blood directly, circumventing the lungs—require some time to set up, during which the patient’s organs might be damaged. Ordinarily, if oxygen gas is injected into a patient, it is likely to form bubbles in blood vessels, blocking blood flow. The microspheres prevent such blockages.

Methods: The researchers used sound waves to mix oxygen and fatty molecules called lipids into a foam of oxygen-­containing microspheres. They then selected spheres around two to four micrometers in diameter and diluted them in a solution commonly used in transfusions. The microparticles are small enough to flow through tiny blood vessels that air bubbles could block.

Next Steps: More animal tests will help determine whether the microspheres could help in clinical situations such as cardiac arrest or severe bleeding. The team is also working on making the microspheres more stable, with the ultimate goal of creating an off-the-shelf treatment for emergencies.