Blood Type (ABO and Rh) Made Simple!

welcome everybody today's exciting lecture is going to be regarding blood typing now why is blood typing important because if you're involved in medicine in any way whether it's laboratory or the clinical battlefield you will be involved with blood typing in some sort so blood typing is important when when somebody says they have a positive blood what does that actually mean well we're going to cover that we're going to talk about the blood type system that's gonna be the most common blood type system but we're also going to deal with the RH system as well and then also we'll cover at the very end some clinical examples and we'll nail this home so that way when someone says a blood type you'll understand the mechanism of what it actually means instead of just memorizing what it is you're going to understand kind of why they came to that naming so we're really going to nail this home by the time you're done here you really should have a good picture of what's going on and to begin we're going to start with the system have a couple housekeeping terms that I want to that I want to take care of just so you're on the same terminology page that I'm going to be talking about so we've got antigen the word antigen what is an antigen well it's going to be a marker everything is going to express some type of antigen it's going to be the marker it's going to be the molecules on the outside of that cell that distinguish it yes I am a red blood cell or yes I am a thyroid so whatever everything is going to have antigen bacteria is going to have antigen our own cells will have antigen anything that's foreign is going to present with a foreign antigen so it's just simply a marker it'll mark this cell next we've got this thing called an antibody an antibody also known as an immunoglobulins shorthand IG so an immunoglobulin is going to be made by the immune system the immune system and what it is is it's going to be a little little marker here that kind of is in the shape of a why has it's composed of two heavy and two light chains for today it has a sticky end over here and this sticky end is going to go and look at the different markers now each immunoglobulin is specific to one antigen so the antibody is specific to one antigen now would it make sense for our body to produce antibodies against our own naturally-occurring antigens so let's say we have a cell here and it has squiggly antigen on the outside so it has squiggly antigen now all of a sudden our body is making these our immune system is making these antibodies against the squiggly antigen it makes no sense why would we want to attack our own cells instead the body decides to down-regulate this and we get rid of all the self reacting antibodies however if this doesn't happen that's where we get autoimmune reactions autoimmune reactions are simply where our body is going to make antibody against our own self naturally occurring antigen typically our body gets rid of that so antibodies are going to bind antigen so that's that's the basics now we can actually move into blood typing so you've got four cells here we're going to use some examples we've got four red blood cells hence why they're drawn in red kind of worked out well we're going to have blood type A blood type B blood type a B and blood type O so these will come from four separate patients so each one of these blood red blood cells is going to come from a separate patient now I'm going to use I'm going to kind of dumb this down a little bit and use shapes because I think shapes help demonstrate what this is all about the best so we've got different antigens remember antigen is going to be the cell marker so for patient a who has type A blood you're going to have rectangles rectangles will be the a antigen the B antigen will be a square so let's talk about this really quick the first patient is going to have blood type A so this is the blood type so their blood type a they're going to express a whole bunch of a antigen on the surface of their red blood cells they're going to mark their red blood cells with the a antigen and you get your blood type based on genetics so your genetics is going to be what determines this so it's going to go through inheritance and you're able to predict but that'll we won't cover that right now but you're able to show what antigen is on the outside of your red blood cell based on inheritance so for patient a they're going to have a whole bunch of a antigen on the outside of their red blood cells notice how they don't have any squares which is going to be our B antigen our B antigen and someone that has B type blood is going to have a whole bunch of B antigen oh the antigen okay so for patient a you know I'm actually going to exit out in my email right now so that doesn't happen again okay we've got a whole bunch of a antigen on blood type a on blood type B you have a whole bunch of B antigen so what are we going to expect to see on blood type a B a B is going to have a mix of the two they're going to have one allele an allele is just a gene that's transferred and it can be modified so that allele for the a antigen it'll have an allele for the B antigen as well so you're going to get a mix of cell surface markers of antigens for blood type O when you see blood type O think there are zero antigens I mean there are antigens but there's no a or B antigen and those are the may this is the main blood typing system of the body so if you see blood type O it kind of looks like a zero you're going to think zero antigen so there's going to be no antigen you don't have you don't have the a antigen you don't have the B antigen that's all this means is what antigens are expressed if you have blood type A you're expressing a antigen if you have blood type B expressing B antigen a B expresses both and O expresses none now this is very important maybe I already know this and that's good because this is very simple but you have to have a very good understanding of this because once you talk about anti a and anti B vs. up versus people who create antibodies against the other stuff you kind of have to go to have a good foundation which which we can build upon so this is the basics of the blood type system now there's thing called the Rh factor all it is is it's simply measuring for a D antigen if you have the D antigen you're Rh positive if you don't have it you're Rh negative so again a red blood cell now in this picture right here we show that we only have one antigen on the cell surface in reality there's multiple there's tons of antigens on the cell surface however we just focused on the a and the B one there now we're just going to focus on the Rh factor which is going to be our D antigen so let's draw this as a circle if if our red blood cell here has red or white circles on its cell surface that'll indicate the D antigen and then we've got a red blood cell over here that doesn't so based on that that's that's our antigen right there so the circles mean the D antigen based on this this cell would be Rh positive and then this cell would be Rh negative so we have an Rh positive cell expressing this D antigen and this cell not expressing it okay so that's the basics give the a B and the RH systems the categories are already talking about now we kind of get to the clinical aspect we covered the very basics important basics that that's where everything clinically derives from so when I say anti a antibody what we're going to be doing is we're going to get some red blood cells we'll take some blood from a patient and what we'll do is we'll expose it to anti a antibodies will also expose it to anti B will expand and also we will expose it to anti D so there are multiple lab tests that we can do we can do anti a anti B anti D and then we can also figure out whether it's a couple other types but we're just going to focus on these three for right now so anti a antibody what it is is it's an antibody remember antibodies bind antigen and it's going to look for a antigen now anti a antibody it's going to be an antibody that binds a antigen so if we do an anti a antibody test it'll be positive only when we find that a antigen so we have our blood types we have the a B a B and O so we have the different blood types and let's figure out um anti a antibodies well we know a antigen is expressed in a positive or in a blood type a patient's so we would see a reaction there and this positive is when you see in a reaction so when the antibody binds to its antigen it's going to cause a reaction it can coagulate so we're going to have some sort of coagulation and this would indicate a positive test anti a antibodies in blood of patient and a patient of type B blood you won't see a reaction there is no a antigen present because this is anti I only looks for a antigen there's no antigen together is an a antigen on blood type a B so you will see a reaction there and then for blood type O you will not see a reaction because there's no antigen on blood type O none whatsoever I mean there is but there's no a antigen there's no B antigen that's all we care about right now now the same thing for anti-b antibodies we're going to look for the B antigen and when we see the B antigen it will be a positive test result will see that coagulation of the patient's blood so for anti B you will not see it in blood type A patients you will see it in blood type B you will see it in blood type a B and you will not see it in blood type O so if the patient's blood has no anti a and no anti-b antibodies it's blood type O and then if they express both anti a and anti B positive reactions then it would be blood type a B hopefully this is making sense this is this is taking what we learned earlier and applying it to more of a clinical basis so we've got anti a plus anti B blood type a B would be positive in both of these cases not to be confused with a B positive however a B blood would show a positive reaction that's what I was going for I'll erase it though because I don't want it now we're going to talk about the anti D antigen and to talk about the anti D I'm just going to go into some examples because that's probably the easiest way to teach us so we've got a negative blood hey will you pass me a unit of a negative blood does that mean well that means that the blood type in the system is we have an a antigen present that should say antigen misspelling is off right now so we have a antigen present what does this negative mean well remember the negative is going to correlate with our Rh factor so if we say the blood type is a negative the a comes from the system it's either a B a B or o this positive negative stuff comes from the Rh factor so when I say it's Rh negative its negative for the D antigen which is kind of what this show this cell is showing meaning it has no circles or D antigen on its surface so let's go back here so a negative means we're going to have eight eight but we're not going to have B or D antigen a B negative would mean you would have antigen a and antigen B but again you don't have antigen D be positive be positive means you'll have antigen B present and you're going to have antigen D present this antigen d the D antigen is going to indicate that it's Rh the Rh positive then lastly we'll go to all positive all positive we're not going to have a we're not going to have B but we will have a d marker we're going to have that D antigen present so these are some of the examples now let's let's go a little further now we're going to go to the concept of a universal donor and a universal acceptor of blood who's a universal donor so let's say you're in the emergency department you're either on a rotation or you're in charge of patient care and your patient is bleeding profusely now you need to get them some packs of some red blood cells you need to unit of red blood cells for example your your attending or your Proctor or whoever you're under or or you yourself says what blood type do I need to get we don't have time to do the lab studies to find out what blood cells we can't do those anti a or anti B or anti D testing that's that's kind of the hallmark we can't do that testing we don't have time our patient is bleeding profusely we need to get them some blood right now and we're going to do that by by getting some donor blood now who is the universal donor we're going to get some donor blood well how do we find that out well it's going to be o- o- blood now why do I say that it's because we're not going to have any antigen on its surface that we're concerned about in Rh subtype systems we're not going to have so we're not going to have any a antigen we're not going to have any B antigen and we're not going to have any D antigen making this Oneg ative blood well why is that important if they don't have any antigen on its cell surface any antibodies that the patient that's receiving that blood has in their system in their plasma in their bloodstream wherever those antibodies are they will not bind because there is no antigen on the cell surface remember I said you have an antibody a B binds to antigen remember that so if you have no antigen you might have these antibodies but they can't bind so this blood is considered the universal donor o negative blood that is a very high yield concept to remember and now we know why it's because there's no antigen on its cell surface when there's no antigen on its cell surface antibodies can't bind antibodies can't bind and coagulate antibodies like to look for foreign stuff but this doesn't look foreign because there's no markers that says foreign now on the other hand the Universal acceptor the Universal acceptor is going to be the patient that can take any blood type okay so what patient can take any blood type well if you want to think of a guess right now I'm just going to say it because then we can talk about it so it's going to be an a B positive or negative okay good you're thinking positive it's going to be an 8 B positive patient now let's let's think of why this is true you've got a red blood cell here you've got that a e antigen remember the triangle you've got the B antigen which was the square then you've also got this D antigen which is going to be a circle so you've got the a B and the D which makes sense we've got the a the B and remember positive negative based on that presence of the D antigen positive good so our naming kind of correlates to our picture here now remember I said that you have antibodies IES okay we have antibodies those go around and look for antigen except our immune system likes to kill off the antibodies that are self reactive so if you have a self reactive antibody we'll get rid of it so in this patient they would have antigen a so all those a antibodies which look like wise they get killed off all the B antibodies we have beyond the normal cell surface so those antibodies get killed off then lastly we have the D antigen which is here so those D antibodies would go and bind however we naturally present with D antigen as well so we're going to get rid of those so our body is making no antibodies against a they're making no antibodies against B or D so we can take any blood type let's say in a positive cell and the triangles and love the circles well we don't make antibodies to those they can also accept O Negative o negative is naked has no antigens so but good I mean we don't make antibodies against it anyway so the universal acceptor has all of the antigens present all of the antigens present trill triggers that immune system to get rid of those self reactive antibodies against the a B and D antigen so we're going to produce no antibodies against it no antibodies means no cross reaction or no coagulation good thing these are high-yield subjects to remember the universal donor Universal acceptor we're going to go back to the anti a concept I just popped into my mind the anti a antibody is going to be a test that's done in the laboratory so what's going to do is we have all of these antibodies that we know are against the a antigen we know that this antibody right here only reacts with the a antigen so when we have some patient's blood here that has that a antigen then it'll cross react so this is done in the lab so that's an important concept to remember so going back over everything we talked about the system we talked about the RH system and we also talked about some clinical kind of vignettes so just in summary right now I'm going to create a little table so blood type a blood type B blood type a B and blood type O so blood type over here then we'll do compatibility compatibility up there even know it's not supposed to compatibility so what blood type is type a compatible with so remember and go back the universal donor is o-negative Universal acceptor is a B+ they're really in search of o-negative donors so going here blood type a is going to be compatible with up with a now does that make sense of course likewise blood type B is going to be compatible with B blood type a B can be compatible with a or B well blood type O is going to be compatible with only blood type O okay that makes sense that is easy so now let's talk about a plasma so this is compatibility of blood I guess I should have been a little more specific now we're going to talk about plasma plasma contains antibodies so if we transfuse some plasma from a patient when we transfer when we transfuse that plasma it's going to also transfuse their antibodies well that's not good but we can use kind of a rule here and this rule is going to figure out whether or not we're going to have reaction so in someone with type A blood they can receive plasma from somebody I guess here we can also throw an O into all of these I'm looking okay with someone from type A blood they can receive plasma from someone to type a plasma again a no brainer but they can also accept plasma from somebody that is a B+ now let's think about this you're saying o be a ba ba ba doesn't stand for that it stands for uh-oh this doesn't make sense well yes it does so in someone that has blood type a B that means they're not going to produce antibodies against a or B because remember and someone with blood type a B their plasma is not going to contain antibodies against a or B they don't want to create self attacking antibodies so they will not have antibodies against B they will not have antibodies against a in their plasma so blood type a is going to be safe there's going to be no a or B antibodies in this plasma you're safe here for patient B it's the exact same thing patient with B is safe and a B is safe as well so if someone's type B blood you can transfuse them with plasma from someone who is a B+ now let's talk about what antibodies are going to be present in someone with a antigen so blood type a we take some of their plasma and we're going to give it to a patient that plasma will contain no anti a antibodies so they'll only have antibodies against B that makes sense but here we can give it to a because they don't have any B antigen so who cares we have antibodies against B but doesn't matter so I'm making a little sense hopefully it is that it's it's an important concept I mean blood compatibility is a little easier but then plasma compatibility you really have to think about antibodies and and to think about antibodies you have to think about if someone who is a B+ or who has a B blood donated their Platt they're not going to have antibodies against a they're not going to have antibodies against B you have to kind of think about this I mean we're taking the basic science that that I covered at the beginning and now we're integrating it that's where the fun comes in okay someone with a B+ blood what plasma can they receive well they're kind of limited they're kind of out of luck they can receive plasma from people who are a B+ only and to do that I'm going to put a little comma afterwards so that way only a B+ because since they have both antigens you have to have donor who doesn't produce antibodies against a or b so there's nothing else they're kind of all alone and lastly blood type oh now what can a plasma can they get well remember how I said here they're the universal donor well for plasma they're going to be the universal plasma acceptor so they can receive plasma from someone of course Type O but also they can receive plasma from someone who is a someone who is B type blood and someone who is a B blood well why is that because in these examples not the oh well I guess in the Oh in these examples right here the patient is making antibodies so here the patient's plasma will have anti a and anti B it doesn't matter they don't have antigens here they'll be producing antibodies against the B antigen don't matter they don't have antigens here they'll produce ant antibodies against antigen a doesn't matter they don't have antigens and here they don't have any antibodies produced well that's good because there's no antigen so that's where the plasma comes in so the universal plasma donor is going to be the a B while the universal plasma let's see let's say that right the universal plasma donor is going to be a be the universal plasma accepter is going to be type oh okay anything else that I should talk about let me go back to my beginning said just kind of let's see any other clinical aspects off the top of my head that I can think of I don't think so if you have any questions be sure to ask me up we covered the system we covered the RH system and lastly we talked about a couple clinical vignettes we talked about the universal acceptor and donor of blood we talked about plasma transfusions and who can receive what hopefully I made it clear enough if I didn't be sure to ask questions because I typically respond within a day or two depending on how busy my schedule is I do love answering questions to get you points for your tests to help you understand concepts so thank you very much for paying attention if you have any questions feel free to comment also I love comments just in general like if you learned something builds up my ego a little bit you know and then lastly subscribe for more great videos thanks

Channel: Simple Science Answers

Views: 381,305

Rating: 4.7551336 out of 5

Keywords: blood type, different blood types, abo system, abo blood system, abo blood type, rh blood, what is rh blood type, universal blood donor, universal blood acceptor

Id: e62ClW7H15I

Length: 29min 41sec (1781 seconds)

Published: Mon Jun 10 2013