They dissolve gases, moving oxygen from the lungs to vital organs and remote regions of the body and cleansing the body of carbon dioxide. In surgery, the fluorocarbon delivers to the body about twice as much oxygen twice as fast as the same amount of the blood's own hemoglobin. And because these particles are tiny compared to the body's red blood cells, they can swirl freely through the body's 60,000 miles of capillaries and breeze through blocked arteries in heart attack or stroke victims. Pellegrini and other doctors who are using the oxygen carrier say the benefits are obvious. But some downsides are noticeable, too.
Patients sometimes get flu-like symptoms as their bodies try to filter the substance from the blood.
Alliance said neither is a significant side effect, but federal officials say much more analysis is needed before the product can be judged for safety. Alliance hopes to have tested Oxygent on more than 1,000 patients by the end of the year. And more trials, including emergency cases, will likely follow. Even so, side effects that only occur once in every 10,000 cases may remain hidden. Eventually, the FDA must decide if the risk of what is still unknown outweighs the benefit of a substitute for blood.