In a radical departure from the way experimental drugs and medical products are usually studied, Cook County Hospital is poised to begin testing a substitute for human blood on trauma patients unable to give their consent.
The testing at County Hospital is part of a major national study that, if successful, could lead to widespread use of the first substitutes for human blood.
Like human blood, the substitute--which is made with hemoglobin--is a red liquid. But unlike blood, it need not be matched to a patient's type and can be given to anyone.
By using the blood substitute on trauma patients, researchers hope to significantly reduce the number of patients who die because properly matched human blood is unavailable or not available quickly enough. The testing, which would take place at County Hospital and elsewhere in the country, would result in 850 patients receiving the experimental product.
Patients typically must be told of the risks and asked for their approval before participating in a medical experiment. But this approach, called informed consent, is not feasible for the most critically injured patients in emergency rooms and trauma centers.
The federal government is expected--perhaps within weeks but almost certainly before the end of the year--to sign off on a set of rules for experimental therapies on people unable to consent to such treatment.
Once that happens, an advisory panel of experts and consumer advocates chosen by County Hospital will review the study and set guidelines for informing the community, perhaps through advertisements or a public-service campaign. If all goes as planned, the study will begin in the Cook County trauma center this year. Additional medical centers throughout the country would join in shortly thereafter.
The blood substitute, called HemAssist, contains hemoglobin extracted from banked human blood that expired before it could be used. The hemoglobin--the substance in red blood cells that carries oxygen to organs--is pasteurized and purified to eliminate viral contamination. It then is put in a solution that can be administered intravenously.
The product has been tested on nearly 500 people who consented, such as patients who granted approval before surgery.
The blood substitute might carry health risks, including raising blood pressure, some experts have said. The Food and Drug Administration is tracking HemAssist and other blood substitutes that are being tested on patients who can provide consent at medical centers around the country.
"We have a product that works which is blood, so you want to be able to show this has a different function and/or works as well or is as safe," said Lenore Geld, a spokeswoman for the FDA in suburban Washington.
As medical knowledge advances, researchers, physicians and the federal government have been grappling with how to test new and potentially more effective treatments on the most seriously injured people while simultaneously respecting their rights.
"It is a serious issue when you do studies without informed consent," said Thomas Schmitz, general manager of the blood-substitutes program for Baxter International Inc., the Deerfield-based company that hopes to do the study.
"We obviously believe this kind of research is necessary," he said. "If we don't do it, we'll end up with second-class medical care for emergency situations."
Dr. Roxanne Roberts, associate director of the Cook County trauma unit, said that if the experimental product proves safe and effective, it would "absolutely" improve the chances of survival for many emergency patients.
Among the problems faced in emergency rooms are that type-testing and matching of blood can take 20 to 40 minutes, specific types of blood might not be available or limited and the risk of transmitting blood-borne diseases such as hepatitis--though small--is not zero.
"We are not going to get the run-of-the-mill trauma patient," Schmitz said. Instead, only those patients whose chances of dying are estimated by doctors to exceed 30 percent will be given the blood substitute without consent.
"You've got to go with the most seriously injured," he said. "Most of the rest survive with or without our help" because trauma centers are so adept at saving lives.
Roberts predicted that the blood substitute will soon be tested at County Hospital.
"All the signs look very good that they are going to allow us to proceed," she said.
The attempts to find a substitute for blood date back hundreds of years. In modern times, the military has been especially interested in finding a blood substitute that could be used in field hospitals. The public became interested in the topic after some people contracted the virus that causes AIDS through transfusions of tainted blood.
Although the risk of such infection today is minimal, blood usually cannot be used more than 28 to 42 days after it is donated. That means there can be critical shortages when blood demand is heavy.
The blood substitute that Baxter is testing can be stored for about a year.
Whether the blood substitute will perform well enough to merit federal approval and widespread use is something the study will show. Researchers who study and develop substitute blood products said they are hopeful but cautious.
"Mother Nature is not entirely forthcoming about all of her secrets," said Richard DeWoskin, chairman of the board of Northfield Laboratories Inc. in Evanston, which is developing competing blood substitutes.
"Sometimes," he said, "it takes longer than you might imagine to come up with the answers."