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Chapter Summary:
In this chapter we learned about blood. Blood is a very complex connective tissue. Blood is composed of red blood cells, white blood cells, platelets and blood plasma. We also learned about blood typing. Not all blood types are compatible with each other. This was demonstrated in lab as well when we were able to mix our own blood with the antibody serum and see if agglutination occurred or not. We also learned about what composes the blood within our bodies and how different types of blood cells are composed. For example, white blood cells look much different than red blood cells.

Plasma:
Plasma is the liquid portion of our blood. Plasma is composed of mostly water with some solutes that have been dissolved. Plasma makes up approximately 55% of our blood. Plasma contains proteins that make up between 7% and 9% of the plasma. These proteins are albumins, globulins and fibrinogen. Albumins responsible for maintaining the pressure in the vascular system that draws water into the capillaries. Albumins are made in the liver and although they are the smallest of the plasma proteins, they are the most abundant. Albumins make up approximately 70% of the plasma proteins.
Globulins are broken up into three different types. Alpha, beta and gamma globulins. Alpha and beta globulins are responsible for transportation of lipids through the blood stream. Alpha and beta globulins also transport vitamins that are fat-soluable through the blood stream. These globulins are produced in the liver. Gamma globulins have a much different function. They do not function as transporters, but rather they function in the immune system. Lympohocytes produce the gamma globulins and they are considered to be antibodies that aid in fighting infections. Fibrinogen are the last type of plasma protein. Fibrinogen functions as a clotting factor in the blood. When a blood clot is needed, fibrinogen is converted to fibrins that make the blood thicker and form a clot. Fibrinogen is produced in the liver and makes up only about 4% of blood plasma.

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Formed Elements of Blood:
Blood contains many different types of cells. They are red blood cells also called erythrocytes, white blood cells also called leukocytes and platelets. The red blood cells are the second major component of our blood, second to plasma. They compose approximately 45% of our blood. Red blood cells are flat, disk-shaped cells that contain no nucleus and have a life span of only about 120 days. The erythrocytes get their red color from the 280 million hemoglobin molecules they each contain. The hemoglobin in the red blood cells are responsible for picking up oxygen from the lungs and transferring it to the tissues through the blood stream. red blood cells are produced in the bone marrow at the rate of about 200 billion each day.
Leukocytes or white blood cells compose a very small portion of our blood but they are very important. White blood cells are small and can move themselves out of the blood stream to a site of infection. They have a nucleus and are only visible under a microscope when they have been stained. Leukocytes are classified based on their staining abilities. Leukocytes that are granular in appearance when they are stained are called granular leukocytes. When leukocytes are stained, a mixture of pink to red and blue to purple stain is used. Granular leukocytes that will absorb the pink stain are called eosinophils. Granular leukocytes that will absorb the blue stain are called basophils. Leukocytes that do not absorb any stain at all are called neutrophils. There are only two types of white blood cells that are not granulated. These are lymphocytes and monocytes. Lymphocytes are small and have a large nucleus that takes up most of the cell space. Lymphocytes have very little cytoplasm because the cell does not have room for the cytoplasm. Monocytes are large leukocytes and have a very large kidney-shaped nucleus. Monocytes have a larger cytoplasm than a lymphocyte does. Lymphocytes are the second most abundant leukocytes, second to neutrophils.
Platelets are the last of the formed elements of blood. Platelets are the smallest of the blood elements and lack a nucleus similar to leukocytes. Platelets are responsible for the clotting of blood. Platelets contain phospholipids that are responsible for activating other clotting factors such as fibrinogen in the blood plasma. Platelets have a short life span of only 5 to 9 days. When platelets attach together to form a blood clot, they release a chemical called serotonin. Serotonin then constricts the blood vessels in the area of the clot which reduces blood flow and helps the clot to seal off the break in the blood vessel.

The video below summarizes the components and function of the different types of blood cells.






Blood Typing:
Blood typing is done for many reasons. The most common reason being to cross-match patients when a blood transfusion is needed. When blood is typed, a sample of blood is mixed with antibodies of all types of blood. When antibodies and antigens of non-compatible blood are mixed together, they will clump up. This clumping indicates that the blood is not compatible with that type of antibody. For example, when type A blood is mixed with anti-A antibodies (which are found in type B blood) we know the blood cannot be type B blood because clotting would occur. When the antibodies that are found in the blood sample are mixed with the same antibodies, no clumping will occur and that indicates what type of blood the sample is. For example, type A blood is mixed with anti-B antibodies (which are found in type A blood) and no clumping occurs. This lack of clumping indicates that the sample contains the same antibodies as the ones that are added, indicating that the blood sample is type A blood.

Application to Nursing:

Nurses are often responsible for giving blood transfusions to patients. When these transfusions are given, the blood must be checked to ensure that it is the correct type for the correct patient. When blood is checked, it is checked by a minimum of four people, two of those people being nurses. Nurses must know which blood types are compatible with each other. Serious complications can arise if the incorrect type of blood is given to the patient. If a nurse were to give type B blood to a patient who had type A blood, that patient would suffer a serious reaction. The blood would have what is called an agglutination reaction and the blood can clot off small blood vessels. This reaction can also cause rupture of red blood cells called hemolysis. In order to ensure the utmost of patient safety, the nurse must understand not only the compatibility of different blood types, but the consequences of giving the wrong type of blood to a patient. Nurses must also be able to explain the concept of blood compatibility to their patients. Often blood transfusions can be a scary experience for a patient and the question of why a different type of blood is being given comes up. If a type A patient were to see that they were getting type O blood, they may not understand why and may be concerned that the type O blood is not compatible with their own. The nurse must be able to easily explain blood compatibility to the patient so they understand why they are getting a different type of blood and that they do not need to be concerned about it.

Essential Question:

"Create a chart that shows the antigens and antibodies of the ABO +/- blood typing system. Also include on your chart, which blood types are compatible. Describe what happens at the molecular level when blood types are not compatible (major crossmatch). What blood type is considered the universal donor and why? What type is considered the universal recipient and why?"

Blood Type
Antigens
Antibodies
Compatibility
A
A
Anti B
Can receive A or O only
B
B
Anti A
Can Receive B or O only
O
None
Anti A and Anti B
Can Receive O only
AB
A and B
None
Can Receive AB, A, B or O
When blood types that are not compatible are mixed, the antibodies of one and the antigens of the other react and clump together. Antigens are present on the red blood cells. Antibodies are present in the plasma. I will use type A and type B blood as an example. Type A blood has type A antigens that are triangle shaped (just as an example). Type B blood has B antigens that are square shaped. Type A blood has antibodies for type B blood and these would be square shaped because they are designed to fit the antigens on type B blood. If type B blood were given to a type A person, the antibodies in the type A blood will bind together with the type B blood cells and this will cause a clumping together reaction. This reaction is called agglutination. When blood types are cross-matched, the agglutination reaction is what determines if they are compatible or not. Blood that is compatible will not react because the antibodies in the recipient's blood will not bind with the antibodies on the donor blood and no agglutination will occur.

The blood type that is considered the universal donor is type O blood. Type O blood does not have antigens on it at all. Without antigens, agglutination cannot occur. Agglutination cannot occur because the antibodies on the recipient's blood will have no antigens to react with.The antibodies of the recipient's blood will need to fit onto the antigens of the donor blood. Because O blood lacks antigens completely, it is able to be mixed with any other type of blood and reaction will not occur.

The blood type that is considered the universal recipient is type AB. Type AB people can receive blood that is type A, B, O or AB. Type AB blood lacks antibodies completely. Because of the lack of antibodies, type AB blood cannot react with antigens that are on any other type of blood and agglutination cannot occur.This concept is the same as with type O blood but only in reverse. Because AB blood has no antibodies, it is not capable of binding together (agglutinating) any other type of blood.


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