Blood derivatives and fractions

 

This week, the discussion of blood medicine moved from academic to personal.

If you are a regular reader of this space, you know my feelings about blood. I’ve written more than a dozen columns about it. Here are links to some of those columns:

Advances in Blood Medicine

Government, Parental Rights and Medical Treatment

Hyperbaric Oxygen Therapy for Blood Loss

Why Blood is Bad Emergency Medicine

You Must Know about TXA Before Your Next Operation

Spread the word: Transfusion is NOT a “life-saving procedure”

 

The reason I said it went from academic to personal: My wife is preparing for hip replacement surgery, and we had a pre-op meeting at the hospital. I nearly always accompany her to such meetings to make sure we ask enough questions and to compare notes afterward.

But this time, when her name was called, the nurse made it clear I was not included in the invitation. When Wifey came out, she told me the nurse questioned her about her stand on blood.

“Are you sure you want to refuse all blood and blood derivatives?”

My wife wasn’t sure she’d heard correctly. “Derivatives?”

“Because we can just get rid of that form you signed, if you wish. No one has to know,” the nurse went on.

When my wife explained she wanted no blood or blood components, but that she might accept some fractions on a case-by-case basis, depending on what the fraction was, the nurse claimed she was unfamiliar with the terms “components” and “fractions”. 

I’m profoundly glad I wasn’t there for that conversation. The nurse would no doubt have been offended at my loudly questioning how she could possibly have ever passed her Medical Ethics class.

Did we get it wrong? Has medicine moved on from “components” and “fractions” to “derivatives”?

No. Medical science decidedly has not. But in a world where people claim to be confused about their pronouns, word definitions are not as clear-cut as they used to be.

It could have been simple vagueness on the part of the person who designed the form. That seems unlikely. Could it be that the hospital is trying to get patients to sign something that lets them off the hook for not precisely following the patient’s wishes?

If you sign the form as written, you have severely restricted what the institution can use to treat you. But if you don’t sign it as written, they may well give you blood.  

“Blood derivatives” is a commonly used billing term that includes whole blood and the four major blood components – plasma, red blood cells, white blood cells, and platelets – as well as the blood fractions made from those components. So of course you are not going to give permission to be treated with any and all “blood derivatives”. But you may not want to blanketly rule out all fractions, either.

Without a clearer definition you could be cutting yourself off from literally dozens of fractionated medicines: clotting factors for when your wound won’t seal up; and the opposite - medications for when you have thrown or they’re afraid you might throw a dangerous clot; and dozens of other blood-derived medications for use in rarer circumstances.

Whole blood is rarely transfused anymore. At a blood collection center, a single unit of blood is treated to break it into 3 parts: the red blood cells are collected; the platelets are also collected out separately. The remainder… the plasma, still containing the white blood cells (called Leucocytes), clotting factors, and other more esoteric derivatives may or may not be further treated.

The plasma may be treated by freezing and thawing, a process called cryoprecipitation. At the proper in-between temperature they can lift out some of the clotting factors, though they are still somewhat contaminated with some plasma and some white cells. That product is called cryoprecipitate. The remaining plasma is called cryosupernatant. Both these products have significant risk of transmitting disease.

The majority of the cryosupernatant in the U.S. market is shipped to a manufacturer to be “pooled”. The pool is comprised of donations from thousands or even tens of thousands of individuals. Most of the individual units have been tested for: Lymphotropic virus, HIV, Hepatitis B & C, Syphilis, Chagas disease, West Nile virus and Babesia.

However, no testing is done for over 60 known blood-borne diseases. In some cases, because there is no test; in other cases, because the blood collection center deems the risk to be remote. A collection site in Oregon isn’t going to check for Chikungunya, a disease common in Latin America (even though my brother-in-law who lives in Oregon has it.) ONE of the units going into the pool may well carry one of those diseases. It if does, it pollutes the entire pool.  One unit of blood containing Chikungunya or Parvovirus or Malaria or yellow fever could potentially spread that virus to every one of the thousands of patients who receive blood-based medicine manufactured from that pool.

Most fractional blood derivatives have trade names, like Zemaira, Albuminex, or Corifact. All are supposed to come with a Drug Fact Sheet.

The Drug Fact Sheet for Zemaira, for example (a medication for people with emphysema), says:

“Because Zemaira is made from human blood, it may carry a risk of transmitting infectious agents, e.g., viruses, and theoretically the Creutzfeldt-Jakob disease (CJD).” (CJD, in case you’re unfamiliar, used to be called Mad Cow disease.) “The risk of transmitting an infectious agent has been reduced by screening plasma donors for prior exposure to certain viruses, by testing for the presence of certain current virus infections and by inactivating and removing certain viruses. Despite these measures, such products can still potentially transmit disease.”

Has anyone ever been diagnosed with Mad Cow from taking Zemaira? I don't know. However, it is listed there because people have contracted CJD from transfusions of various blood components.

Some derivative Drug Fact Sheets specifically mention, ‘pooled blood’, or they may have the warning similar to ‘you could get Mad Cow’; others seem to be more adamant that their product when used correctly is totally free of any threat of catching something from someone else. Here’s the pertinent part of the label from a product called Kedbumin:

“Albumin is a derivative of human blood. Based on effective donor screening and product manufacturing processes, it carries an extremely remote risk for transmission of viral diseases and variant Creutzfeldt-Jakob disease (vCJD). There is a theoretical risk for transmission of Creutzfeldt-Jakob disease (CJD), but if that risk actually exists, the risk of transmission would also be considered extremely remote. No cases of transmission of viral diseases, CJD or vCJD have ever been identified for licensed albumin.”

However, the FDA warning label for albumin says:

“Albumin (Human) 25% is made from human plasma. Products made from human plasma may contain infectious agents, such as viruses, that can cause disease. The risk that such products will transmit an infectious agent has been reduced by screening plasma donors for prior exposure to certain viruses, by testing for the presence of certain current virus infections, and by inactivating certain viruses by pasteurization. Despite these measures, such products can still potentially transmit disease.”

So, I suppose if you need albumin, Kedbumin might be a better choice...maybe? Still, a study about albumin said:

“For patients with hypovolaemia there is no evidence that albumin reduces mortality when compared with cheaper alternatives such as saline. There is no evidence that albumin reduces mortality in critically ill patients with burns and hypoalbuminaemia. The possibility that there may be highly selected populations of critically ill patients in which albumin may be indicated remains open to question.”

What about blood derivatives that are not made from pooled blood?

One type of antithrombin is created by inserting the human DNA that forms antithrombin into a female goat. After some time has elapsed, the milk of the goat will have human antithrombin in it which can be extracted for use as a blood thinner.It is called a blood derivative, but clearly it is far removed from blood.

If you get bit by a rattlesnake you may, depending on your health, need antivenin. Antivenin is made by injecting a small amount of a given species of snake’s venom into a horse, waiting a few days for the horse to build up antibodies, then drawing blood from the horse and filtering out some of its antibodies. Antivenins for other poisonous bites are made similarly.

Every unfamiliar medication your doctor prescribes, you'll want to ask if it is a blood derivative. They're not necessarily all bad. In some cases, depending on how you live, you might be taking greater risks every day. But certainly it is better to be educated. Read your medicine's warning material. If it is a blood derivative it will include the disclaimer, “Because yada-yada is made from human blood it may carry a risk…” or wording to that effect.

“Blood and blood products are likely always to carry an inherent risk of infectious agents. Therefore, zero risk may be unattainable. The role of FDA is to drive that risk to the lowest level reasonably achievable.” – fda.gov

If it is a blood-derived medicine, you might want to ask your doctor if there is another medication, that does roughly the same thing, that is not a blood derivative, such as a synthetic, a recombinant, or some other product. Ask if your need for this medication is life-threatening or if it is merely advisable. Research it yourself to get a better understanding of what it will or won’t do for you. 

I spent many, many hours researching this. The first thing I learned is that it is a really complicated subject. But don't let that put you off. The second thing I learned is that you can understand it if you keep looking things up. Hopefully, this column will serve as a starting point for your research. 

Please copy and share the link to this article with all your friends.  You might keep one of them from catching Chikungunya. 

Please leave a comment.

 Bill K. Underwood is the author of several novels and one non-fiction self-help book, all available at Amazon.com. You can help support this site by purchasing one of his books.