At first glance, artificial blood seems like a good thing. It has a longer shelf life than human blood. Since the manufacturing process can include sterilization, it doesn't carry the risk for disease transmission. Doctors can administer it to patients of any blood type. In addition, many people who cannot accept blood transfusions for religious reasons can accept artificial blood, particularly PFCs, which are not derived from blood.
However, artificial blood has been at the center of several controversies. Doctors abandoned the use of HemAssist, the first HBOC tested on humans in the United States, after patients who received the HBOC died more often than those who received donated blood. Sometimes, pharmaceutical companies have had trouble proving that their oxygen carriers are effective. Part of this is because artificial blood is different from real blood, so it can be difficult to develop accurate methods for comparison. In other cases, such as when artificial blood is used to deliver oxygen through swollen brain tissue, the results can be hard to quantify.
Another source of controversy has involved artificial blood studies. From 2004 to 2006, Northfield Laboratories began testing an HBOC called PolyHeme on trauma patients. The study took place at more than 20 hospitals around the United States. Since many trauma patients are unconscious and can't give consent for medical procedures, the Food and Drug Administration (FDA) approved the test as a no-consent study. In other words, doctors could give patients PolyHeme instead of real blood without asking first.
Northfield Laboratories held meetings to educate people in the communities where the study took place. The company also gave people the opportunity to wear a bracelet informing emergency personnel that they preferred not to participate. However, critics claimed that Northfield Laboratories had not done enough to educate the public and accused the company of violating medical ethics.
Blood substitutes may be used as performance-enhancing drugs, much like human blood can when used in blood doping. An October 2002 article in "Wired" reported that some bicyclists were using Oxyglobin, a veterinary HBOC, to increase the amount of oxygen in their blood.
In spite of the controversy, artificial blood may be in widespread use within the next several years. The next generations of blood substitutes will also probably become more sophisticated. In the future, HBOCs and PFCs may look a lot more like red blood cells, and they may carry some of the enzymes and antioxidants that real blood carries.
See the links below for more information on blood, artificial blood and related topics.
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More Great Links
- Alliance Pharmaceutical. Oxygent. http://www.allp.com/Oxygent/OX.HTM
- BBC. "Patients Given Artificial Blood." 10/23/2003 http://news.bbc.co.uk/2/hi/health/3207291.stm
- Blood Components http://anthro.palomar.edu/blood/blood_components.htm
- Brown University. "Blood Substitutes." http://biomed.brown.edu/Courses/BI108/BI108_2000_Groups/Blood_Substitutes/index.html
- Chang, Thomas Ming Swi. "Blood Substitutes Based on Biotechnology." Trends in Biotechnology. 2006. http://www.medicine.mcgill.ca/artcell/2006trendsweb.pdf
- Chang, Thomas Ming Swi. "Therapeutic Applications of Polymeric Artificial Cells." Nature Reviews. March 2005. http://www.medicine.mcgill.ca/artcell/2005NatureRev.pdf
- CNN. "Artificial Blood Tested on Patients Without Consent." 2/20/2004. http://www.cnn.com/2004/HEALTH/02/20/blood.substitute.ap/
- Coghlan, Andy. "Unconscious Decision: A Life and Death Dilemma." New Scientist. 10/25/2006. http://www.newscientist.com/channel/health/mg19225743.700-unconscious-decisions-a-life-and-death-dilemma.html
- Davis, Lisa. "The Chemistry of…Blood." Discover. July 2002. http://www.discover.com/issues/jul-02/departments/featchemistry/
- Davis, Nicole. "Better than Blood?" Popular Science. 11/2006. http://www.popsci.com/popsci/science/9e367f36fca9e010vgnvcm1000004eecbccdrcrd.html
- Davis, Robert. "Traumas Create Unwitting Test Subjects." USA Today. 6/13/2006. http://www.usatoday.com/news/health/2006-06-13-traumas-trials_x.htm
- Eslocker, Asa R. and Astrid Hill. "Artificial Blood Experiment: Is Your City Participating?" 7/7/2006. http://abcnews.go.com/WNT/story?id=2166058&page=1
- Euro Blood Substitutes http://www.eurobloodsubstitutes.com/
- Goorha, Brig YK et. Al. "Artificial Blood." MJAFI, 2003. http://medind.nic.in/maa/t03/i1/maat03i1p45.pdf
- McCarthy, Wil. "Strange Blood." Wired. 8/2002. http://www.wired.com/wired/archive/10.08/blood.html
- Muramoto, Osamu. "The Watchtower Society Redefines Guidelines for Use of Blood Products." http://www.ajwrb.org/6-15-04.shtml
- Northfield Laboratories: PolyHeme. http://www.northfieldlabs.com/polyheme.html
- Orfinger, Becky. "South Africa Approves First Blood Substitute." 4/19/2001. http://www.redcross.org/news/bm/intl/010419sub.html
- Picard, Andre. "The Red Blood Cell Man." McGill News. Winter 1996. http://www.medicine.mcgill.ca/artcell/mcgillnews.pdf
- Selim, Jocelyn. "The Bionic Connection." Discover. 11/2002. http://www.discover.com/issues/nov-02/features/featbionic/
- Tanner, Lindsey. "Ethicists Blast Study Testing Fake Blood." USA Today. 3/2/2006. http://www.usatoday.com/tech/science/discoveries/2006-03-02-blood-substitute_x.htm
- Tortora, Gerard J. and Sandra Reynolds Grabowski. Principles of Anatomy and Physiology. John Wiley & Sons. 2000.
- University of California Jacobs School. "Artificial 'Blood.'" http://www.jacobsschool.ucsd.edu/cover_story/2003/Nov-Dec/NovDecPage3.html
- Westphal, Sylvia Pagan. "New Artificial Blood Shows Promise." New Scientist. 3/13/2004. http://www.newscientist.com/article.ns?id=dn4760
- Willet, Kari. "How Do Scientists Make Artificial Blood? How Effective Is it Compared to the Real Thing?" 10/21/1999. http://www.sciam.com/askexpert_question.cfm?articleID=0007ACC0-ACD3-1C71-9EB7809EC588F2D7