@Mangetout local shortages are always an issue. But the blood banks are quite assertive at working to keep their supplies of O negative up.
I’m O+ and have been a fairly regular blood donor my whole life. We have Vitalent here to take our blood. I get those texts all the time about shortages and then I take a look and things are booked for a week. It makes me think that those texts aren’t very regional.
Thank you to everyone who donates.
As an aside - and hopefully not a hijack - it would be reasonable to wonder, in this day and age, Why has nobody developed an artificial oxygen carrying blood substitute? Your target product profile would be no (or vastly reduced) incompatibilities; longer shelf-life; no need for refrigeration…
It’s been done, but not financially successfully. I was peripherally involved in development work on one of these - better not say which.
My impression was that one reason the products never really gained traction was that the current arrangements work well; plus I presume cost would be a major issue. I don’t remember the technical reasons which prevented more widespread licensing of the ones which did manage to get a licence somewhere in the world.
@Dr_Paprika @Qadgop_the_Mercotan - anything to add?
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@Treppenwitz Issues are manifold in the search for oxygen carriers.
For the hemoglobin based substitutes, one needs a source of hemoglobin, in LARGE amounts. Bovine hemoglobin has been looked into, but the details of managing large herds of cows to harvest their hemoglobin have been daunting. Concerns of prions causing causes of Creutzfeldt-Jakob/bovine spongiform encephalopathy have been raised. Massive production of human derived hemoglobin by cloning technology faces many technical and regulatory issues.
Cost of this is also a concern. US regulations don’t allow for much discussion of eventual costs of producing these drugs, nor their eventual market price prior to their development. But some estimates have indicated cost would be at least double of current blood products.
The research done so far for hemoglobin based oxygen carrier products have also been plagued by a lot more side effects and complications seen versus standard blood product therapy.
Perfluorocarbon based oxygen carriers (such as you refer to) have been looked at too. And indeed one product was approved for use in 1989 in the US for a specific situation: ischemic issues during angioplasty. But it was not a commercial success and is no longer made. Further trials to see how this type of carrier might do in other situations were cancelled due to inability to find enough study patients.
So: what we’ve got currently is pretty good, as long as we keep getting willing donors, and we’ve got over a century of experience with that practice. And developing substitute products is hampered by the need for the product to be a big money maker, to get investment in the idea (at least in the US).
It’ll be interesting to see where it goes. My money is on better management of patient bleeding during emergencies, more recycling of the patient’s own blood, plus even better pharmacologic and surgical interventional techniques to get the bleeding to stop (yes, I know all bleeding stops eventually, but you know . . .).
The last line says it all: hard to use, doesn’t work as well, more side effects. Probably costly as well. There are many issues with using blood but also a working system and much experience with managing them.
My first thought was “why not culture real blood using stem cells or the like?”
I see that Treppenwitz’s link mentions that approach, called “blood pharming.” But the links from Wikipedia, and even Googling only produce ancient stuff, like >5 years old. Did the idea just not pan out? Why does there seem to be no recent research in this direction? It seems to be a much easier problem than, say, cultured organs.
@Dr.Strangelove My source (UpToDate, an evidence based medical website for current practice standards) has this to say about culturing red cells:
"Cell culture — Advances in cellular engineering have made it possible to culture red blood cells (RBCs) in vitro from hematopoietic progenitor cells, which may represent an exciting, viable approach to meeting global red blood cell transfusion needs. Potential sources of hematopoietic progenitor cells include umbilical cord blood, adult peripheral blood, multipotent stem cells, and immortalized adult erythroid progenitor cells.
In a proof of principle study in mice and a human volunteer, transfused RBCs cultured from autologous CD34 cells demonstrated attributes consistent with endogenous RBCs such as oxygen binding and release, deformability, enzyme content, expression of ABO antigens, and viability. This is an exciting step, but considerable challenges to the large-scale production of RBCs for therapeutic transfusion purposes exist, including significant biologic, regulatory, funding, and logistic issues." Bolding mine.
I’ve no idea the current state of research, my sources focus on what’s happening TODAY in the clinics, not the labs.
It’s done by Medical Technologists working in the hospital Pathology Lab. The same people and place that do most of the blood/urine/stool/body fluid/etc. tests that the physicians order. I haven’t worked Blood Bank since 2006 but back then it only took a few minutes to get a ABO Rh type. An antibody screen took around half an hour while actually identifying any antibodies could take up to several hours depending on circumstances.
If someone with Rh negative blood doesn’t already have Anti - D (Rh antibody) then giving them Rh positive units won’t be a problem, at least for the first occasion. I’ve seen it done a few times when blood supplies were tight. Once the bleeding was controlled then they were switched back to Rh negative units. Also, not everyone exposed to Rh positive blood this way will necessarily develop antibodies. People’s immune systems vary a lot and if someone is bleeding excessively the donor units may not stick around long enough to trigger a response.
In general, there is a gap of fifteen to twenty years between first conducting research in a lab and eventual use in the clinic.
Thanks, that makes sense. I’m not too surprised that it has taken a while to get to clinical use, just that there seemed to be a gap in any progress at all. But it is likely that it is either just being worked on quietly, or my keywords aren’t right, or something along those lines.
I expect so. I also expect, with all the covid disruptions, other issues, etc. that there’s not a big push for research in that area, frankly. We usually have sufficient blood product to meet our needs in the US, at a not exorbitant cost.
Those patients who would benefit from the artificial product over the what we now use are few and far between, and frankly most of them are Jehovah’s Witnesses, who would refuse not only current blood products, but anything derived from human or animal, via cloning or stem cells.
But it would be nice to have other tools in the toolkit to employ when a patient needs more oxygen delivery to their tissues, and our current blood products can’t do the job.
Do you know of any situations where unlimited blood would be a benefit? Suppose it only cost $1/liter–cheap enough to pump into someone faster than it could possibly drain. No big deal if you use 10,000 liters. Or do you really not think at all about the quantities needed?
You do. Giving too much might throw off other things. You want to maintain reasonable blood pressure, make sure all the tissues are oxygenated (avoid shock), keep the patient hydrated, keep all the electrolytes, platelets, etc. within a limited range. Also, in reality supplies are limited.
However, if you were in Gothic novel…
Anecdote: at the height of the Younger Ottlet’s (ongoing) battle with Crohn’s she needed blood transfusions every 2-3 weeks. Since she developed new antibodies with each transfusion, by the time things abated she was waiting 8-10 hours for them to find blood that her system would accept.
Thank you for your knowledgeable posts here. In the case of the OP question, would plasma help?
Sadly, they won’t take my blood. The head tech said it was some unknown antigen, and he’d take my blood himself, but rules are rules. 
In the OP’s scenario where massive blood loss is occurring, plasma, with its clotting factors can help buy some time, if one is also infusing large volumes of of crystalloid like saline, to keep blood pressure up.
But unless the loss of red blood cells is halted before they get too low, the patient will die.
The patient needs something to carry oxygen to the tissues, and the only thing available to 99.999999999% of patients in the world that can do that are red blood cells full of hemoglobin.
I celebrated my 17th birthday by donating blood for the first time, and donated every 8 weeks for a long time after that, but once I started having a lot of low blood sugar episodes from reactive hypoglycemia, and came very close to passing out after donating, my doctor thought I should stop. And now, some of my insomnia medications might keep me from donating, but that’s a more recent issue.
I did donate a little over a gallon before I had to stop.
I’m A+. Not a universal donor, but the most common type, so they liked me coming in too. After I had to stop, they kept calling me for a few years, even though I told them my doctor had advised me not to.
When I was in pharmacy school in the early 1990s, we had to invent and write a marketing plan for a drug. You guessed it- one classmate proposed artificial blood, and another oral insulin.
My older-student friends and I all came up with joke products (which was certainly allowed); one of my friends had InSync, which made men want to dance, and another had GenderAid, which would enable a man to produce nothing but X or Y sperm depending on what kind of baby they wanted to have. Me? I had Xanthrix, a oral med which made hair blond. And yes, you could take it intermittently to make stripes if you wished.
Anyway, blood is a far more complicated organ (and yes, it is an organ, a liquid organ) than most people realize.
Fluosol! I think I saw it a time or two; the name is familiar.
Good story about the history of artificial blood, although not surprisingly, it’s quite technical.