Most people understand that each individual has a blood type and that that type is important for blood transfusions, but what exactly makes it so important? Is it life threatening, or is it just a mild inconvenience? Let’s get into the data and see what you need to know before you’re performing an emergency transfusion!
Disclaimer: I am not a medical expert of any kind, and you should take this merely as my opinion. Always check with your doctor concerning anything about your blood, as the complexities of even the most basic issues of a transfusion are beyond the scope of a simple blog post. Finally, this advice is intended only for a survival situation without any access to doctors or medical care.
Blood types: what’s the big deal?
Blood typing is extremely important when taking blood from one person and giving it to another. Poorly matched blood can kill the receiver rapidly, with symptoms including kidney failure often occurring within just 24 hours of the initial transfusion. The reason for this is that although everyone’s blood tends to appear identical to the human eye, on a microscopic level your blood has a great deal of individuality. Indeed, although most people are familiar with the two primary differences between blood types (The ABO System and the RH system that makes a blood type positive or negative) there are some 30 additional characteristics that can make a difference in whether donor blood is accepted or not. The two primary ones are the most obvious indicators of compatibility, but there are situations where people have experienced harm from same-type blood that had a less common secondary characteristic that rejected the new blood.
The two primary indicators of blood compatibility
That said, in an emergency you simply will not have the complex and technical equipment needed to determine if blood will be 100% compatible, and will need to rely on the primary indicators in the absence of an operational hospital. The ABO System (which gives blood their letter names including A, B, O, and AB) and the RH System (Which adds the + or – sign to the end, as in A+ or B- Blood) may not be perfect, but they are certainly better than just pumping in some blood and seeing what happens!
The ABO system
This indicator is the best known, and many people who know little of the medical field may still take an interest in their blood type out of curiosity if nothing else. There are 4 blood groups within this system: A, B, O, and AB. Each is an indicator of which kind of antigen floats about in your own blood stream. Your body came to recognize whatever antigens were initially present in your early years as the “normal” ones, and sees the opposite as invaders. A and B antigens fight against one another, which is why A and B type blood cannot be shared. AB type blood has both A and B antigens, and thus easily accepts pure A or pure B blood in addition to other AB donor sources. Blood type O is unique in that it has neither A nor B antigens, which means that the body will make antibodies that fight both A and B antigens and can accept only other O blood.
When donating, same types are always compatible in this system, meaning that A can always donate to A, B to B and so on. AB is the universal recipient, able to accept A, B, AB, and O blood owing to the presence of all the antigens in its system. O can donate to all because no other type fights against O blood, but the O type donor cannot accept A, B, or AB blood because O rejects everything but additional O blood. It should be noted that unless circumstances dictate otherwise, it is usually preferred to use blood that is the exact same type regardless of normal compatability: thus a best case scenario is always A-A, B-B etc. Mixing of types should only be done when needed. The ideal would be to store your own blood beforehand and then simply use that when the need arose to minimize the chance of complications, but it is unlikely that you will be able to do that in a survival situation.
It should be noted that in some countries blood typing under this system is often considered to be an indicator of personality and temperament, but that is complete hogwash. If you do work with or intend to survive with the aid of someone who is under the impression that blood types determine personality, I recommend doing some simple research and eliminating that obstacle if possible.
The RH system
ABO is simple but you might like to have a chart to remember everything. The RH system is incredibly simple to remember by contrast, as there are only two groups, positive and negative. Positive means that you can receive positive or negative blood. Negative blood can only receive other negative blood. When paired with the ABO system as it should be, this means that the most open blood type is AB+, while the most difficult match would be O- which could only receive from other O- donors or from themselves. As such, ABO and RH should always be listed together when making notes on blood types, as giving a negative person positive blood is just as bad as improperly mixing types.
How to know your type
There is no physical indicator of blood type, so the best bet is to donate some blood and have them tell you what type you ended up being. Alternatively, you can also contact your doctor and see if you have had it tested in the past and had the type checked. Anyone who has undergone any situation where they might need to receive blood probably has it recorded in their file. If you feel like spending money, you can also purchase a kit that will allow you to test yourself. However, donating your blood not only helps others and gets you a free blood test but can also identify other common bloodborne ailments when they test it for proper quality.
Blood typing is very important for anyone looking to survive a disaster. Make sure you know your type and that you know which blood can go from donor to recipient!
Do you know your blood type? Do you keep it recorded somewhere just in case you are injured? Let us know in the comments below!
This article first appeared at Prepared For That: Understanding Blood Types for Survival