May lead to improved treatments where oxygen is critical in sustaining life

Detroit, MI. Researchers at Wayne State University are working on improved methods of infusing aqueous oxygen into the blood stream that may one day improve treatments where oxygen is critical to sustaining life. Examples include infusing aqueous oxygen into the aorta to supply oxygen to lungs that function inadequately in patients on a ventilator with severe pneumonia; shock from any cause where blood flow to major organs is low; reperfusion problems such as renal failure after shock; severe infections; and tumors that are resistant to radiation therapy because they are hypoxic.

J. Richard Spears, M.D. professor of Internal Medicine at WSU’s School of Medicine, and his research team previously discovered that small capillary tubes can be used to deliver water that is supersaturated with oxygen and other gases into host liquids without bubbles. The researchers developed a model that explained the effect of confinement in progressively small spaces on increasing thresholds of metastability. This technique has been so successful that oxygen-supersaturated water, termed aqueous oxygen, is being used in randomized clinical trials to hyperoxygenate blood for improving results of angioplasty and stenting of blocked coronary arteries in patients with myocardial infarction.

Dr. Spears and his research associate, Petar Prcevski, DVM, along with Giles Brereton, Ph.D. from Michigan State University’s College of Engineering, advisor on the theoretical aspects of this project, have taken this approach one step further, and have been investigating how to eliminate the main drawback to this approach which is the need to remove excess water associated with prolonged infusions of aqueous oxygen. The latest research done by this team could provide a potentially practical result by reducing the amount of water needed when aqueous oxygen at high concentrations is used to hyperoxygenate the whole blood volume without bubbles.

When a champagne bottle is uncorked, or when water is brought to its boiling point, the result is predictable – profuse bubbles appear. This is a result of the rapid growth of gas or vapor nuclei process, heterogeneous nucleation. Nuclei typically reside within numerous microscopic crevices of the container’s wall or in tiny particulates floating in the liquid. But, can bubbles form if there are no nuclei? According to Dr. Spears, a theory known as homogeneous nucleation predicts they do, but only if the liquid molecules are stretched apart at great tensions.

Bubbles have always been noted in water at values less than ones predicted for homogeneous nucleation. Now, this research team has demonstrated that water can be supersaturated with helium up to a record-breaking level without bubble nucleation when the water is released to atmospheric pressure. At this pressure at room temperature, 2.4 kbars (1 kbar = a thousand atmospheres), water contains 15 ml of helium per gram of water despite its very low solubility. For oxygen, which is much more soluble than helium, only 0.7 kbars was required to deliver 13 ml per gram of water in a bubbleless manner into host liquids.

“Dr. Spears’ research is at the center of a multi-site clinical trial to determine if hyper-oxygenation therapy will make a difference in the recovery of patients who have had heart attacks,” said Fred Reinhart, assistant vice president for Research and Technology Commercialization at WSU. “This latest discovery could make such therapies more attractive and open the door to additional hyper-oxygenation interventions for other diseases or conditions,” Reinhart added.

This research study was supported by a Michigan Life Science Corridor grant and is published in the latest issue of the American Society for Artificial Internal Organs, a bimonthly journal for cardiothoracic surgeons, transplant physicians, biomedical engineers and many others that features the latest research, development and application of biomaterials, advances in the design of artificial organ devices and findings from initial testing.

Wayne State University is one of the nation’s pre-eminent public research universities in an urban setting. Through its multidisciplinary approach to research and education, and its ongoing collaboration with government, industry and other institutions, the university seeks to enhance economic growth and improve the quality of life in the city of Detroit, state of Michigan and throughout the world.