What is blood?
Blood is a living tissue that circulates through the heart, arteries and veins and organs carrying nourishment, electrolytes, hormones, vitamins, antibodies, heat and oxygen to the body's tissues.

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What is whole blood?
Whole blood is just as it sounds-it is blood with all of its components intact. Whole blood contains red blood cells, white blood cells and platelets suspended in a proteinaceous fluid called plasma. These parts can be separated from whole blood in order to provide patients with superior treatment by giving them the specific elements they need. It also eliminates waste by excluding non-essential components for each particular treatment. Whole blood donations can be made every eight weeks (56 days).

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Red blood cells are prepared from whole blood by removing the plasma, or the liquid portion of the blood, and can raise the patient's hematocrit and hemoglobin levels while minimizing an increase in blood volume.

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How are red blood cells used?
Patients who benefit most from transfusions of red blood cells include those with chronic anemia resulting from disorders such as kidney failure, malignancies, or gastrointestinal bleeding and those with acute blood loss resulting from trauma or surgery. Since red blood cells have reduced amounts of plasma, they are well-suited for treating anemia patients who would not tolerate the increased volume provided by whole blood, such as patients with congestive heart failure or those who are elderly or debilitated.

Red blood cells may be treated and frozen for extended storage (up to 10 years).

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What is plasma?
Plasma is the liquid portion of the blood--a protein-salt solution in which red and white blood cells and platelets are suspended. Plasma, which is 90 percent water, constitutes about 55 percent of blood volume. Plasma contains albumin (the chief protein constituent), fibrinogen (responsible, in part, for the clotting of blood), globulins (including antibodies) and other clotting proteins.

Plasma serves a variety of functions, from maintaining a satisfactory blood pressure and volume to supplying critical proteins for blood clotting and immunity. It also serves as the medium of exchange for vital minerals such as sodium and potassium, thus helping maintain a proper balance in the body, which is critical to cell function. Plasma is obtained by separating the liquid portion of blood from the cells. Fresh frozen plasma is frozen within hours after donation to preserve clotting factors, stored for one year, and thawed before it is transfused.

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How is plasma used?
Plasma is most often used to treat certain bleeding disorders when a clotting factor or multiple factors are deficient and no factor-specific concentrate is available. It can also be used for plasma replacement via a process called plasma exchange.

Cryoprecipitated AHF (CRYO) is the portion of Plasma that is rich in certain clotting factors, including Factor VIII, fibrinogen, von Willebrand factor and Factor XIII. Cryoprecipitated AHF is removed from plasma by freezing and then slowly thawing the plasma. It is used to prevent or control bleeding in individuals with hemophilia and von Willebrand's disease, which are common, inherited major coagulation abnormalities. Its use in these conditions is reserved for times when viral-inactivated concentrates containing Factor VIII and von Willebrand factor are unavailable and plasma components must be used.

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What are platelets?
Platelets (or thrombocytes) are very small cellular components of blood that help the clotting process by sticking to the lining of blood vessels (basically, they form scabs). Platelets are made in the bone marrow and survive in the circulatory system for an average of 9-10 days before being removed from the body by the spleen. The platelet is vital to life, because it helps prevent both massive blood loss resulting from trauma and blood vessel leakage that would otherwise occur in the course of normal, day-to-day activity. Units of platelets are prepared by using a centrifuge to separate the platelet-rich plasma from the donated unit of whole blood. The platelet-rich plasma is then centrifuged again to concentrate the platelets further.

Platelets may also be obtained from a donor by a process known as apheresis, or plateletpheresis. In this process, blood is drawn from the donor into an apheresis instrument, which, using centrifugation, separates the blood into its components, retains the platelets, and returns the remainder of the blood to the donor. The resulting component contains about six times as many platelets as a unit of platelets obtained from whole blood. Platelets are stored at room temperature for up to seven days.

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How are platelets used?
Platelets are used to treat a condition called thrombocytopenia, in which there is a shortage of platelets, and to prevent bleeding in patients with abnormal platelet function.

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What are white blood cells?
White blood cells are responsible for protecting the body from invasion by foreign substances such as bacteria, fungi and viruses. The majority of white blood cells are produced in the bone marrow, where they outnumber red blood cells by two to one. However, in the blood stream, there are about 600 red blood cells for every white blood cell. There are several types of white blood cells. Granulocytes and macrophages protect against infection by surrounding and destroying invading bacteria and viruses, and lymphocytes aid in the immune defense. Granulocytes can be collected by apheresis or by centrifugation of whole blood and are transfused within 24 hours after collection.

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How are white blood cells used?
White blood cells are used to fight infections that are unresponsive to antibiotic therapy and to produce interferon. The effectiveness of white blood cell transfusion is still being investigated.

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What is Apheresis?
An increasingly common procedure is apheresis, or the process of removing a specific component of the blood, such as platelets, and returning the remaining components, such as red blood cells and plasma, to the donor. This process allows more of one particular part of the blood to be collected than could be separated from a unit of whole blood. Apheresis is also performed to collect plasma (liquid part of the blood) and granulocytes (white blood cells).

The apheresis donation procedure takes longer than whole blood donation. A Whole Blood donation takes about 10-20 minutes to collect the blood, while an apheresis donation may take about 90 minutes. The benefits of an apheresis donation are plentiful. Not only can an apheresis donor produce a higher volume of a specified blood component when they donate, they can donate more often-as many as 24 times per year for platelets and 12 times per year for plasma.

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Who Needs Apheresis Products?
Patients with cancer or leukemia, transplant recipients and patients with blood disorders need apheresis products. Chemotherapy and radiation treatment destroy healthy cells and platelets are needed to prevent bleeding.

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What is our blood volume?
The blood volume in a healthy adult amounts to 8% of total body weight. For example, if you weigh 100 lbs., 8 lbs of blood is circulating in your body. An average size female has about nine pints of blood, while an average size male has about 12 pints of blood.

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How does the body make blood?
Red cells, platelets and white cells are made in the bone marrow. Coagulation proteins (clotting factors) are made in the liver and water comes from the body's general fluid content.

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What is bone marrow? Donating Marrow
Marrow is a substance found inside bones. It resembles blood and contains stem cells, which produce red blood cells, white blood cells and other blood components important for fighting infection, carrying oxygen and helping to control bleeding.

Stem cells, the cells that transplant patients need to make new healthy marrow, usually live in bone marrow, but are also released, in small numbers, into the circulating (peripheral) blood. There are several treatments that will dramatically increase the release of stem cells into the circulating blood so that enough stem cells for transplant can be collected directly from the bloodstream.

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How long can we store blood?
Red blood cells can be stored for up to 42 days at 1-6°C and 10 years if frozen. Platelets must be kept at room temperature and expire in 7 days. Fresh frozen plasma and CRYO must be stored at -18°C for no longer than 1 year.

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What is blood type?
There are four groups of blood, the A group, the B group, the AB group and the O Group. All of these groups can either be Rh negative or Rh positive, thus producing the eight basic types of blood. Your Blood type is inherited from your parents and does not change.

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How do they determine blood type?
Forward typing:

• If your blood clots when it is mixed with anti-A serum, then you have type A blood.
• If your blood clots when mixed with anti-B serum, then you have type B blood.
• If your blood clots when it is mixed with both anti-A and anti-B serums, then you have type AB blood.
• If your blood does not clot in the presence of either serum, then you have type O blood.
• If your blood clots when mixed with anti-Rh serum, then you have type Rh-positive blood.
• If your blood does not clot when mixed with anti-Rh serum, then you have type Rh-negative blood.

Reverse typing:

• Clotting that occurs when B cells are mixed with your serum indicates you have type A blood.
• Clotting that occurs when A cells are mixed with your serum indicates you have type B blood.
• Clotting that occurs when your serum is mixed with both types of cells indicates you have type O blood.
• Lack of clotting when your serum is mixed with both types of blood indicates you have type AB blood.

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What is the most common type of blood?

• O Rh-positive 37% (1 in 3)
  O Rh-negative 7% (1 in 15)
  A Rh-positive 36% (1 in 3)
  A Rh-negative 6% (1 in 16)
  B Rh-positive 8% (1 in 12)
  B Rh-negative 2% (1 in 67)
  AB Rh-positive 3% (1 in 29)
  AB Rh-negative 1% (1 in 167)
  

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What blood types are compatible?
The rules of blood transfusion are as follows. Any patient who is Rh-negative must receive Rh-negative blood. Patients who are Rh-positives (Rh) can receive Rh-negative or Rh-positive blood. Patients with group O must get group O. Patients with group AB can recieve any group. O Negatives are "Universal Donors" while AB Positives are "Universal Recipients." The following chart will help to illustrate compatibility.

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