Are Synthetic ‘Blood Substitutes’ Currently Available in the United States?
Are blood substitutes currently available?
The simple answer is No. The term 'blood substitute' has been applied to products which have the property of transporting oxygen which is a major function of blood. Patients who refuse blood transfusions have an intense interest in this subject as any product which could serve as even a partial replacement for transfusions could be potentially very useful in their care.
Products that transport oxygen in place of blood essentially fall into two categories: synthetic products containing no blood products and hemoglobin based oxygen carriers.
Synthetic products containing no blood products
A product made without any blood product that would transport oxygen would be of great interest to Bloodless Patients. Products of this nature are being developed and tested as transfusion alternatives. To this point, none of these products have been approved for general use in the United States.
Hemoglobin Based Oxygen Carriers
These products are genetically engineered using hemoglobin obtained from either bovine or human blood. Products of this nature are being developed and tested. Hemoglobin is a fraction obtained from Red Blood Cells. Patients who object to blood transfusions on the basis of religious conscience may individually decide whether or not to allow the use of a product containing hemoglobin. None of these products are currently approved for use in the United States.
Updates on products such as these may be obtained from the U.S. Food and Drug Administration website which is www.fda.gov.
The following information appears on other pages in MyBlood’s website and is included here for the reader's convenience
Volume expanders - intravenous fluid replacement – Instead of using blood to replace lost blood volume expanders replace the fluids that are lost during surgery. They also maintain lost volume –one of the main reasons blood has traditionally been used for.
Colloids – colloids contain proteins, starch or gelatin.
Colloidal solutions – a group of intravenous fluids containing purified water, salts, and sugars. They may be given to replace the fluids, salts, and sugars that are lost during surgery or as volume expanders. Many who refuse a blood transfusion on grounds of religious conscience may accept colloidal transfusions.
Crystalloid solution – a group of intravenous fluids containing purified water, salts, and sugars. They may be given to replace the fluids, salts, and sugars that are lost during surgery or as volume expanders. Many who refuse a blood transfusion on grounds of religious conscience may accept crystalloid transfusions.
D5W (A water solution with 5% dextrose) - (basically - water and sugar)
Hetastarch – an intravenous fluid. The main components are distilled water and amylopectin (a natural polymer of glucose found in plant starch.)
Lactated Ringer’s Solution / Ringer’s Lactate – a volume expander that contains in decreasing amounts sodium ion, chloride ion, lactate, potassium ion and calcium ion.
Normal saline solution – basically sterile water and salt (sodium chloride) used as a volume expander.
Pentastarch – an intravenous fluid consisting of distilled water and amylopectin (a glucose found in plants) and used as a volume expander.
Saline / Saline solution – often used in Bloodless Medicine as a volume expander in cases of blood loss. It is a solution of sodium chloride (salt), sterile water and sometimes dextrose or glucose. It is generally administered to a patient as an intravenous (IV) infusion or through an IV drip.
Volume expanders can be used in conjunction with Acute Normovolemic Hemodilution:
Acute Normovolemic Hemodilution (ANH) – Acute Normovolemic Hemodilution is a preoperative hemodilution - preoperative (that is it is begun immediately before or after anesthesia is administered and prior to the actual surgical procedure) - hemodilution (dilution of the blood.) The preoperative hemodilution procedure is induced by the isovolemic exchange (an exchange of mass or fluids wherein volume is maintained) of whole blood with volume expanders, to preserve the patient’s blood while maintaining normal blood volume in the patient’s body. It can eliminate the need for homologous blood (blood from another person) and is a common procedure in Bloodless Surgery. It is also known as Isovolemic Hemodilution (IVHD or IHD) or Intraoperative Hemodilution.
Although recycling a patient’s blood is not a bloodless transfusion it is a type of transfusion where homologous blood is not transfused but rather the patient’s blood is transfused back into his own body. The procedure is accomplished by means of a cell salvage machine, the most common being the Cell Saver®.
The role of volume expanders in Bloodless Medicine
These non-blood fluids are used to increase the volume of fluid in the circulatory system. When a patient bleeds excessively during surgery the volume of fluids in his circulatory system drops and the patient can slip into shock. Volume expanders increase the volume back to normal without transfusing whole blood or blood products.
Bloodless transfusions are safe. They accomplish a vital task in restoring blood volume and avoiding shock
Exotic synthetic blood substitutes, may be years away from FDA approval. Bloodless Medicine has, in the meantime, made great advances in Bloodless Surgery - surgery without using homologous blood. The technology is safe, approved by the FDA and is here now.
The following information also appears on other pages in MyBlood’s website and is included here for the reader’s convenience
No synthetic blood substitutes
So far, there is no real substitute for human blood. But researchers are working to develop a synthetic blood substitute that will not have the risks of blood transfusions. Products that are being tested include hemoglobin-based oxygen carriers and perfluorochemical compounds. They can do some of the work of red blood cells, such as carrying oxygen to tissues, but they do not replace human blood. Of the 2 oxygen-carrying compounds that are being tested in US clinical trials, neither has been approved by the FDA as of early 2008.
Compassionate use only
Most blood substitutes are experimental and are rarely used. They may be used as a temporary measure in patients whose religious beliefs do not allow them to have blood product transfusions. They may also benefit patients with rare blood types and those whose immune systems would destroy available donated blood. The substitutes may be used until matching donated blood can be found, which in some cases might take several days. -cancer.org
Oxygen-carrying blood substitutes
As of 2008, there are no widely utilized oxygen-carrying blood substitutes for humans; however, there are widely available non-blood volume expanders and other blood-saving techniques. These are helping doctors and surgeons avoid the risks of disease transmission and immune suppression, address the chronic blood donor shortage, and address the concerns of Jehovah's Witnesses and others who have religious objections to receiving transfused blood.
A number of blood substitutes are currently in the clinical evaluation stage. Most attempts to find a suitable alternative to blood thus far have concentrated on cell-free hemoglobin solutions. Blood substitutes could make transfusions more readily available in emergency medicine and in pre-hospital EMS care. If successful, such a blood substitute could save many lives, particularly in trauma where massive blood loss results. Hemopure, a hemoglobin-based therapy, is approved for use in South Africa. -wikipedia.