Blood Purge

The adult human body contains about five quarts of blood. If more than half of this is removed at one time, the owner usually dies. Scientists in Russia claim to have removed the entire blood supply from animals, chemically "washed" it, replaced it without apparent injury. Scientists everywhere would consider this an extremely dangerous experiment for humans. Yet it might be possible to detour the bloodstream so that only a few ounces would be outside the body at any one time, yet so that all of it would pass sooner or later through the detour where it could be treated for blood infections or impurities.

So reasoned Drs. Kenneth Cooley of Rochester and Kristian Gosta Hansson of Cornell. To physical therapists convened in Cincinnati last week Dr. Hansson described a machine designed by himself and his associate which pumps blood out of one arm, irradiates it with germicidal ultraviolet rays, puts it back in the other arm. Citrate of sodium introduced into the blood as it leaves the vein prevents coagulation. ''It is for the future," said Dr. Hansson, "to show what can be accomplished. One difficulty in experiments was that we didn't know the safe amount of radiation to give the patient. Another was to prevent loss of heat in the blood. This was overcome by stepping up the motor and increasing the rate at which the blood passed through the tube. We are now able to control the speed."