Blood donation.

[Nemozero]

Any medical buffs know wethe different races could donate blood to each other in d and d? And what would the limits on that.

I looked around and couldn’t come up with a good answer. My original thought was at the least the races that can produce viable offspring (half elf, half orcs and there parents) could donate blood to each other as long as they share a blood type (just like normal human blood donations. A, B, AB,O, A + ect.) but I am not sure that’s accurate.

I have also heard of xenotransfusions with various levels of success. Humans have taken lamb and dog blood and I have heard of humans transferring there blood through a pig while they wait for an organ transfer. ( Makeing the poor piggy’s organs do all the work.)

Of course normally I seriously doubt a d and d character would have the knowledge on how to tell what blood types people are beyond trail and error. But then again that would depend on the campaign in question and there technology level.

This randomly came up in a d and d game I was in and I found it interesting. I am happy to just go with what ever the dm says but would be fascinating to see what others think.

[Mitth'raw'nuruo]

As a practical mater I would say it would have to be a fairly high medical check, and I'm not sure how it would come up in a HP based system. I'd never heard of it before, apparently the first documented case was from a lamb to a person with a successful recovery on the 15th of June 15 1667 anno Domini Nostri Iesu (Jesu) Christi.

Given that knowledge I would allow blood transfusions between any race that fell under a rangers favored enemy list.

[Trampaige]

I suppose it also depends on how often this is supposed to come up... and how often it has come up in the past in the game world.

Either roll a die to see if characters have matching blood type and do a medicine check, they're stabilized and fine.

OR, you run it the high fantasy route and add consequences. A human receiving a blood transfusion from a half-elf or elf might impart temporary/permanent changes to perception, or perhaps some limited sleep/charm resistance. A blood transfusion from a dwarf might suddenly cause them to notice how many feet below ground they are, and always know where true north is.

It starts getting very interested if you take Mitth'raw'nuruo's suggestion and get into blood transfusions from fey, celestial, fiendish, or abberant touched/blooded creatures...

Unfortunately, the latter option would probably result in most parties trying to min/max it and start blood doping each other for racial traits. It probably would necessitate dire circumstances, with real risks to both parties (such as you have to have lost a substantial amount of blood in order for it to make a difference, with associated penalties and risks.)

[Aymon]

There are various divination spells to let you predict if the transfusion will be successful...

[Nemozero]

In the case of my campaign it was just something my character went to do as a role play thing. My character had supper high medicine stat so when I was helping treat someone who had lost a lot of blood I said that is something he would do. The DM said that it wouldn't work between a human and a elf. I was fine with the DM ruleing on that and just role played other medical treatment. But I just thought it was an interesting train of thought.

You raise some amazing thoughts however. I can easily imagine some villain or evil player pumping Celestial blood into them selves to gain there power. cool concept but like you said it could quickly become a problem to give such things to players as they could really min max there stats. I know some warlocks would love to fill them selves with demon blood.

And with a hp system I would limit it to stabilizing a person by sacrificing hp and a high medical check in replacement of a healers kit. Otherwise I can see players running around using every living thing as health potions =P could also work with the healer feat as it sensibly limits the times that will give you hit points to once per long rest. Most of the time 5gp for 3 charges is going to be more appealing that draining blood that may not even work.

One thing I learned about blood transfusion while looking into all this was that one of the early symptoms of getting the wrong blood type is a sudden feeling of dread. And that is something doctors look out for. so that is an interesting little tidbit.

[Trampaige]

I could see having a campaign world where a healer's kit or a heal spell could stabilize somebody temporarily, but to bring someone back from death's door they needed an actual transfusion, which would take more time, use more uses of the kit, and require a sacrifice from somebody (perhaps it takes a short rest duration, and somebody else has to spend 1 or 2 HD to restore 1HD to the downed person? Or both parties take a level of exhaustion instead? Penalties dependent on medicine skill roll?)

Maybe a campaign with an infestation of styrges, or weak vampire spawn, or some other reason that blood loss is a major issue in the campaign, so that it actually comes up in RP scenarios with NPCs, or for players while adventuring. It would definitely be very punishing/gritty realism/make being knocked to 0 have real consequences.

Maybe a particular magical creature or animal is being farmed/bred because their blood has special properties of revival and healing, and can be stored and used in place of humanoid blood for transfusions, or healing potions if injested orally. Entire blood farms exist, not unlike modern cattle rearing.

The PCs are plunged into an intrigue plot after people start winding up dead after bad blood infusions, as rival bloodfarmers poison one another's supplies.

And make it addictive in some way.



....And then you have D&D: True Blood.

[Keltest]

Given that even humans cant typically reliably donate blood to each other, I don't see why, say, elven blood would even have a possibility of acceptance in a human. The human's body just wouldn't even recognize it as blood.

[Vogie]

Yeah... I would say that if you want to have that being a thing that exists, and want it to be 'realistic' I would say that it wouldn't be available between races at all, and only 50-60% chance of success if your race is the same AND both individuals are from the same zone. So southern humans can fairly successfully transfuse with other southern humans, and northern elves with other northern elves, but northern elves and western elves can't, nor could southern humans and eastern humans. That's probably easier than trying to figure out how many blood types there are for each race. For reference, normal IRL humans have 8: A+, A-, B+, B-, AB+, AB-, O+, and O-. Then you have other regional variations (such as sickle-cell blood as a evolution against malaria) and blood issues that can otherwise effect those people

If you want it to be a hook, worldbuilding trait, or plot point you could:

Have blood connoisseur Vampires who have found a way to not only identify the various types of blood but also have found a way to store it for long periods of time
Have a rare race that is a universal donor. They could be an engineered servant race (bloodbag!) or could be a minority that is hunted for this purpose
Introduce blood magic as a rare thing, and masters of hemomancy can alter the type of blood as a part of their magic

[Honest Tiefling]

I can't believe all of you forgot blood borne illnesses! Why would you ever ignore such a fantastic way to screw with the players?

[Regitnui]

They could do it in Eberron, with barrels of preserving pine, the Blood of Vol's (um) "reverence" for the stuff, and House Jorasco making a business out of medicine...

I'd say you need to have a "kin" relationship: human blood could service for half-elves, half-orcs, and humans, elven blood could do elves and half elves (all subraces included. Have a Sun elf realise a Drow just donated blood to save their life), etc.

[Mith]

Depending if you think your world would have a concept of germ theory, the risk of infection would be high as well. I would say if you invest time into researching this, you could make something practical from this. Things like silver hypodermic needles, perhaps using glass apparatus for tubing that is flushed with alchemical solutions to cleanse it of contamination. Things like that.

Instead of blood type, I would rule that if the donor race can breed with the recipient race, the transfusion is possible. As far as a percent success, how about DC 20 Medicine check with a 60% chance of success. Every point you beat the DC gives you a 2% increase of chance of success. Therefore, a DC 30 gives you an 80% of success. Investing in tools gives you a bonus to your Medicine check that can count above a DC 30.

For donor interactions off the top of my head: Humans can donate and receive any race, orcs can do the same except with elven races. All other races besides Elves can only accept from Humans, Orcs, and their own races. Elves can only receive from humans and elves.

As far as effects, this is how I would rule. Note that I have recovery be a long term thing, not all stat drains and HP recovered on a long rest: I would say that 1 unit of blood restores 1 point of CON, or 1 HD + CON mod. of hit points if CON is normal. The donor spends 1 HD to produce the unit that is restored by a day of rest. I would use a similar set up to say whether the donation is successful and uncontaminated.

As far as effects, lets say that the recipient gains 1 random racial trait for 3 days/unit of blood donated. This allows for a quirk without a permanent alteration.

There is probably things I have missed, but this may give people ideas.

[SaurOps]

I can't believe all of you forgot blood borne illnesses! Why would you ever ignore such a fantastic way to screw with the players?

Probably because D&D devotes so much word count to stepping around real world diseases and describes nonsense like filth fever instead? As far as its genre goes, it seems to dive off the deep end and ignore anything from the real world as often as possible.

[Honest Tiefling]

Probably because D&D devotes so much word count to stepping around real world diseases and describes nonsense like filth fever instead? As far as its genre goes, it seems to dive off the deep end and ignore anything from the real world as often as possible.

Yes, but that doesn't mean you can't have magical blood borne diseases that for instance, cause the blood to become acidic. You might have an issue where the character attempts to bleed onto enemies, but it could be fun depending on the tone of your game.

[greenstone]

Don't mix real-world science with fantasy gaming. That way madness lies.

In the real world blood transfusion is a fairly recent invention (late 17th century). I'd argue that the fantasy world of D&D just doesn't know about it. If they did think of transferring blood then they would probably do it by drinking it. :smallamused:

If you did want to do it, I'd say it just works. Elves and Dwarfs and Gnomes are all interfertile so it makes sense that their blood would be compatible.

[Joe the Rat]

So would something akin to Rh syndrome be why some mixes don't have viable offspring?

[RickAllison]

As I understand it, emergency transfusions can work with any blood type with complications. We type blood because the cells get eliminated by antibodies over time. IIRC, this means that anyone can give blood as a stopgap measure, but you have to continually replenish the body and the body is constantly fighting rather than being able to rest. Such a procedure can delay death, but in such a setting is reallly only useful for buying time till you can get a Cleric or such for Revivify.

[Honest Tiefling]

Don't mix real-world science with fantasy gaming. That way madness lies.

If your game hasn't already descended into madness, you have been keeping your players on a VERY tight leash.

Through the thought occurs, couldn't blood transfusions also be handled in a fantasy universe by way of ritual that requires blood from a humanoid as a component? You wouldn't be trying to open a vein and trying to pump it in, but the overall cost is the same. Could work if you want a higher fantasy tone, but want aspects of sacrifice.

[Keltest]

I could see blood being used as a quick and dirty ingredient for health potions, maybe. Take some blood, sprinkle in some wizard farts, season to taste. Boom, youre dying less.

[SaurOps]

Don't mix real-world science with fantasy gaming. That way madness lies.

Or a path that other games have managed quite well, and which D&D hasn't because it has issues.

[Regitnui]

Or a path that other games have managed quite well, and which D&D hasn't because it has issues.

They're really easy to add back in, but they're casualties of 5e's drive for simplicity. All you really need to do is build something around the mummy's attack. (AFB) It should be save or "negative effect", effect persists/worsens over time until save success or death.

[lperkins2]

As I understand it, emergency transfusions can work with any blood type with complications. We type blood because the cells get eliminated by antibodies over time. IIRC, this means that anyone can give blood as a stopgap measure, but you have to continually replenish the body and the body is constantly fighting rather than being able to rest. Such a procedure can delay death, but in such a setting is reallly only useful for buying time till you can get a Cleric or such for Revivify.

Not exactly, but also not too far off. The problem with cross-type transfusions is the recipient's immune system will attack any foreign proteins it identifies. It generally takes time for the immune system to do the identification (3 days is a decent ballpark figure), and then time for it to build up and eliminate the foreign proteins. This means, in an emergency, any blood type can be used for anyone who does not already have antibodies for the donated type. It also can only be done once, since after that the antibodies will be developed. This was a major source of trouble with nacent blood transfusions, since a second donation from the same donor would often result in death, and took a fair while to figure out.

If they already have antibodies, either from prior transfusions, or general blood contact, they will have essentially a sever allergic reaction almost immediately after the transfusion. This can result in anaphylactic shock or vascular collapse, and the transfused blood can end up coagulating, any one of which can easily prove fatal.


To address the question of inter-species blood transfusions, it's actually rather similar to the blood-type issue. See, the blood type issue comes up in pregnancies; if the mother's blood lacks proteins, her immune system can attack the fetus, if she produces the wrong antibodies. In humans, this mostly comes up with 'Rh' factor proteins, but can happen with others too. The fact that you have half-elves and what not means that it is *possible* for the maternal immune system to ignore the foreign proteins produced by the offspring, which means it is not a guarantee that the transfusions would be rejected in every case, with answers ranging from "they're all part of the same species, all 'meta-humans'" like shadowrun to "half-elves are only possible with major magical medical intervention". The answer to that is going to be setting dependent, and is unspecified in any of the WoTC stuff.