All About Blood - Must Read

What Is Blood

Blood is essential for good health because the body depends on a steady supply of fuel and oxygen to reach its billions of cells. Even the heart couldn't survive without blood flowing through the vessels that bring nourishment to its muscular walls. Blood also carries carbon dioxide and other waste materials to the lungs, kidneys, and digestive system; from there they are removed from the body.

Blood carries gases, nutrients and waste products through the body. Blood also fights infections, heals wounds and performs many other vital functions. There is no substitute for blood. It cannot be made or manufactured. Donors are the only source of blood for patients who need it.

One unit of blood can be separated into components: red blood cells, white blood cells, plasma, platelets and cryoprecipitate

Without blood, we couldn't keep warm or cool off, we couldn't fight infections, and we couldn't get rid of our own waste products.

Functions of Blood

The blood is a vital organ which supplies oxygen, food and other essential nutrients, hormones and chemicals to cells throughout the body. It serves as one of the body’s most effective defenses against infection, and it also helps in the removal of toxins and other waste materials.

1. Transports:

• Ø  Dissolved gases (e.g. oxygen, carbon dioxide);
• Ø  Waste products of metabolism (e.g. water, urea);
• Ø  Hormones;
• Ø  Enzymes;
• Ø  Nutrients (such as glucose, amino acids, micro-nutrients (vitamins & minerals), fatty acids, glycerol);
• Ø  Plasma proteins (associated with defence, such as blood-clotting and anti-bodies);
• Ø  Blood cells (incl. white blood cells 'leucocytes', and red blood cells 'erythrocytes').

2. Maintains Body Temperature

3. Controls pH

• Ø  The pH of blood must remain in the range 6.8 to 7.4, otherwise it begins to damage cells.

4. Removes toxins from the body

• Ø  The kidneys filter all of the blood in the body (approx. 8 pints), 36 times every 24 hours. Toxins removed from the blood by the kidneys leave the body in the urine. (Toxins also leave the body in the form of sweat.)

5. Regulation of Body Fluid Electrolytes

• Ø  Excess salt is removed from the body in urine, which may contain around 10g salt per day (such as in the cases of people on western diets containing more salt than the body requires).

Composition of Blood

Whole blood is made up of many components, with each component performing a specific role in the blood’s overall functions. The three main blood elements involved in leukemia are the red cells, clotting cells and white cells which are formed in the bone marrow and lymph nodes and circulate through the bloodstream in a clear fluid plasma.

Red Blood Cells (Erythocytes) contain hemoglobin, an iron rich protein which picks up oxygen as the blood passes through the lungs, transports it, and releases it to organs and tissues throughout the body. A shortage of these red cells, a condition known as anemia, can cause weakness, dizziness, shortness of breath, headaches and irritability.

Clotting Cells (Platelets) are tiny disc-shaped cells which help prevent abnormal or excessive bleeding by forming clots. A deficiency of platelets can cause bleeding of the mucous membranes or other tissues, such as the skin. Unexplained or excessive bruising is characteristic of a platelet deficiency.

White Blood Cells (Leukocytes) play a major role in defending the body against disease producing bacteria, viruses and fungi. There are three main types of leukocytes, with each type performing a specific infection-fighting function.

Monocytes defend the body against bacterial infection.

Granulocytes include neutrophils, eosinophils and basophils. Neutrophils are the predominant type, counting for about 60 percent of all circulating white blood cells. They combat infection by rapidly increasing in number, engulfing and destroying foreign substances. They then die and, in turn, are ingested by monocytes. Once an infection is under control, production of neutrophils returns to the original preinfection count and steady state. Eosinophils and basophils also play infection fighting roles.

Lymphocytes consist of two types of cells which combine forces to create a complex interaction to regulate the immune response. T cells attack virus-infected and malignant cells. B cells produce and release antibodies, or protein substances, which bind to infectious agents and help prevent them from doing damage to the body. A deficiency in any type of normal white blood cell may result in an increased susceptibility to infections.

Blood Cell Growth

The blood, like all human tissues and organs, is composed primarily of cells which are developed enough to perform efficiently. The red, white and clotting cells enter the bloodstream after the maturation process called hematopoiesis, which begins with the production of immature cells in the blood-forming tissue of the bone marrow, spleen or lymph nodes. Actually, only a small percentage of cells are produced in the spleen and lymph nodes. The majority of cells originates and matures in the bone marrow - the spongy meshwork interior which fills the cavities of the large bones.

Blood cells grow in the same general manner as all other human cells. Tissues or organs of the body contain a pool of immature, or undifferentiated cells known as stem cells. These cells begin to divide and mature until they become fully developed, or differentiated cells.

The original cells involved in blood cell production are called pluripotent stem cells, meaning that they contain the characteristics of all the different cell types which make up the major blood cell lines. One of these lines is known as the myeloid line which produces the white cells called monocytes and granulocytes. Another is the lymphoid line which produces lymphocytes. As cells mature, they are released into the blood stream to replace those which have become old and worn out.

Blood cells are not released from the bone marrow until they are "mature enough" to perform efficiently. Normally, immature cells or "blasts" are not present in the bloodstream. A relatively small amount of these cells are contained in the bone marrow, still involved in the growth process. However, blasts normally never constitute more that 5 percent of the bone marrow cells.

The entire blood cell reproduction, maintenance, and destruction cycle is really a highly efficient and orderly process. The abnormal and excessive reproduction of any type of cell obviously disrupts the delicate blood cell balance necessary to sustain the body’s general well-being.

Blood grouping system (ABO)

According to the AB0 blood group system there are four different kinds of blood groups: A, B, AB or 0 (null).

Blood group A

• Ø  If you belong to the blood group A, you have A antigens on the surface of your red blood cells and B antibodies in your blood plasma.

Blood group B

• Ø  If you belong to the blood group B, you have B antigens on the surface of your red blood cells and A antibodies in your blood plasma.

Blood group AB

• Ø  If you belong to the blood group AB, you have both A and B antigens on the surface of your red blood cells and no A or B antibodies at all in your blood plasma.

Blood group 0

• Ø  If you belong to the blood group 0 (null), you have neither A or B antigens on the surface of your red blood cells but you have both A and B antibodies in your blood plasma.

Rh Blood Types

Rh   blood types were discovered in 1940 by Karl Landsteiner and Alexander Wiener.  This was 40 years after Landsteiner had discovered the ABO blood groups.  Over the last half century, we have learned far more about the processes responsible for Rh types.  This blood group may be the most complex genetically of all blood type systems since it involves 45 different antigens on the surface of red cells that are controlled by 2 closely linked genes on chromosome 1.

The Rh system was named after rhesus    monkeys, since they were initially used in the research to make the antiserum for typing blood samples.  If the antiserum agglutinates your red cells, you are Rh+.  If it doesn't, you are Rh- .  Despite its actual genetic complexity, the inheritance of this trait usually can be predicted by a simple conceptual model in which there are two alleles, D and d.  Individuals who are homozygous dominant (DD) or heterozygous (Dd) are Rh+.  Those who are homozygous recessive (dd) are Rh- (i.e., they do not have the key Rh antigens).

Clinically, the Rh factor, like ABO factors, can lead to serious medical complications. The greatest problem with the Rh group is not so much incompatibilities following transfusions (though they can occur) as those between a mother and her developing fetus.  Mother-fetus incompatibility occurs when the mother is Rh- (dd) and the father is Rh+ (DD or Dd).  Maternal antibodies can cross the placenta and destroy fetal red blood cells.  The risk increases with each pregnancy.  Europeans are the most likely to have this problem--13% of their newborn babies are at risk.  Actually only about ½ of these babies (6% of all European births) have complications.  With preventive treatment, this number can be cut down even further.  Less than 1% of those treated have trouble.  However, Rh blood type incompatibility is still the leading cause of potentially fatal blood related problems of the newborn.  In the United States, 1 out of 1000 babies are born with this condition.

Rh type mother-fetus incompatibility occurs only when an Rh+ man fathers a child with an Rh- mother.  Since an Rh+ father can have either a DD or Dd genotype, there are 2 mating combinations possible:

Only the Rh+ children (Dd) are likely to have medical complications.  When both the mother and her fetus are Rh- (dd), the birth will be normal.

The first time an Rh- woman becomes pregnant; there usually are not incompatibility difficulties for her Rh+ fetus.  However, the second and subsequent births are likely to have life-threatening problems.  The risk increases with each birth.  In order to understand why first born are normally safe and later children are not, it is necessary to understand some of the placenta's functions.  Nutrients and the mother's antibodies regularly transfer across the placental boundary into the fetus, but her red blood cells usually do not (except in the case of an accidental rupture).  Normally, anti-Rh+ antibodies do not exist in the first-time mother unless she has previously come in contact with Rh+ blood.  Therefore, her antibodies are not likely to agglutinate the red blood cells of her Rh+ fetus. 

Placental ruptures do occur normally at birth so that some fetal blood gets into the mother's system, stimulating the development of antibodies to Rh+ blood antigens.  As little as one drop of fetal blood stimulates the production of large amounts of antibodies.  When the next pregnancy occurs, a transfer of antibodies from the mother's system once again takes place across the placental boundary into the fetus.  The anti-Rh+ antibodies that she now produces react with the fetal blood, causing many of its red cells to burst or agglutinate.  As a result, the newborn baby may have a life-threatening anemia because of a lack of oxygen in the blood.  The baby also usually is jaundiced, fevered, quite swollen, and has an enlarged liver and spleen.  This condition is called erythroblastosis fetalis.  The standard treatment in severe cases is immediate massive transfusions of Rh- blood into the baby with the simultaneous draining of the existing blood to flush out Rh+ antibodies from the mother.  This is usually done immediately following birth, but it can be done to a fetus prior to birth.  Later, the Rh- blood will be replaced naturally as the baby gradually produces its own Rh+ blood.  Any residual anti-Rh+ antibodies from the mother will leave gradually as well because the baby does not produce them.

Erythroblastosis fetalis can be prevented for women at high risk (i.e., Rh- women with Rh+ mates or mates whose blood type is unknown) by administering a serum (Rho-GAM  ) containing anti-Rh+ antibodies into the mother around the 28th week of pregnancy and again within 72 hours after the delivery of an Rh+ baby.  This must be done for the first and all subsequent pregnancies.  The injected antibodies quickly agglutinate any fetal red cells as they enter the mother's blood, thereby preventing her from forming her own antibodies.  The serum provides only a passive form of immunization and will shortly leave her blood stream.  Therefore, she does not produce any long-lasting antibodies.  This treatment can be 99% effective in preventing erythroblastosis fetalis.  Rho-GAM is also routinely given to Rh- women after a miscarriage, an ectopic pregnancy, or an induced abortion.  Without the use of Rho-GAM, an Rh- woman is likely to produce larger amounts of Rh+ antibodies every time she becomes pregnant with an Rh+ baby because she is liable to come in contact with more Rh+ blood.  Therefore, the risk of life-threatening erythroblastosis fetalis increases with each subsequent pregnancy.

Anti-Rh+ antibodies may be produced in an individual with Rh- blood as a result of receiving a mismatched blood transfusion.  When this occurs, there is likely to be production of the antibodies throughout life.  Once again, Rho-GAM can prevent this from happening.

Mother-fetus incompatibility problems can result with the ABO system also.  However, they are very rare--less than .1% of births are affected and usually the symptoms are not as severe.  It most commonly occurs when the mother is type O and her fetus is A, B, or AB.  The symptoms in newborn babies are usually jaundice, mild anemia, and elevated bilirubin levels.  These problems in a baby are usually treated successfully without blood transfusions.

If your blood type is . . .

Type	You Can Give Blood To	You Can Receive Blood From
A+	A+  AB+	A+  A-  O+  O-
O+	O+  A+  B+  AB+	O+  O-
B+	B+  AB+	B+  B-  O+  O-
AB+	AB+	Everyone
A-	A+  A-  AB+  AB-	A-  O-
O-	Everyone	O-
B-	B+  B-  AB+  AB-	B-  O-
AB-	AB+  AB-	AB-  A-  B-  O-

Interesting Facts

• Almost 40% of the population has O+ blood
• Patients with Type O blood must receive Type O blood
• About half of all blood ordered by hospitals are Type O
• Type O blood is the universal blood type and is the only blood type that can be transfused to patients with other blood types
• Only about 7% of all people have Type O negative blood
• Type O negative blood is the preferred type for accident victims and babies needing exchange transfusions
• There is always a need for Type O donors because their blood may be transfused to a person of any blood type in an emergency
• Someone needs blood every two seconds.
• About 1 in 7 people entering a hospital need blood.
• One pint of blood can save up to three lives.
• Healthy adults who are at least 17 years old, and at least 45kg may donate about a pint of blood – the most common form of donation – every 56 days, or every two months. Females receive 53 percent of blood transfusions; males receive 47 percent.
• 94 percent of blood donors are registered voters.
• Four main red blood cell types: A, B, AB and O. Each can be positive or negative for the Rh factor. AB is the universal recipient; O negative is the universal donor of red blood cells.
• Dr. Karl Landsteiner first identified the major human blood groups – A, B, AB and O – in 1901.
• One unit of blood can be separated into several components: red blood cells, plasma, platelets and cryoprecipitate.
• Red blood cells carry oxygen to the body's organs and tissues.
• Red blood cells live about 120 days in the circulatory system.
• Platelets promote blood clotting and give those with leukemia and other cancers a chance to live.
• Plasma is a pale yellow mixture of water, proteins and salts.
• Plasma, which is 90 percent water, makes up 55 percent of blood volume.
• Healthy bone marrow makes a constant supply of red cells, plasma and platelets.
• Blood or plasma that comes from people who have been paid for it cannot be used to human transfusion.
• Granulocytes, a type of white blood cell, roll along blood vessel walls in search of bacteria to engulf and destroy.
• White cells are the body's primary defense against infection.
• Aphaeresis is a special kind of blood donation that allows a donor to give specific blood components, such as platelets.
• how long most donated red blood cells can be stored- Forty two days
• how long most donated platelets can be stored- Five days
• how long frozen plasma can be stored- One year
• Much of today's medical care depends on a steady supply of blood from healthy donors.
• Children being treated for cancer, premature infants and children having heart surgery need blood and platelets from donors of all types, especially type O.
• Anemic patients need blood transfusions to increase their red blood cell levels.
• Cancer, transplant and trauma patients, and patients undergoing open-heart surgery may require platelet transfusions to survive.
• Many patients with severe sickle cell disease receive blood transfusions every month.
• A patient could be forced to pass up a lifesaving organ, if compatible blood is not available to support the transplant.
• Thirteen tests (11 for infectious diseases) are performed on each unit of donated blood.
• 17 percent of non-donors cite "never thought about it" as the main reason for not giving, while 15 percent say they're too busy.
• The #1 reason blood donors say they give is because they "want to help others."
• Shortages of all blood types happen during the summer and winter holidays.
• Blood centers often run short of types O and B red blood cells.
• The rarest blood type is the one not on the shelf when it's needed by a patient.
• There is no substitute for human blood.
• If all blood donors gave three times a year, blood shortages would be a rare event (The current average is about two.).
• 176 liter of blood you could donate if you begin at age 17 and donate every 56 days until you reach 79 years old.
• Four easy steps to donate blood: medical history, quick physical, donation and snacks.
• The actual blood donation usually takes about 10 minutes. The entire process – from the time you sign in to the time you leave – takes about an hour.
• After donating blood, you replace the fluid in hours and the red blood cells within four weeks. It takes eight weeks to restore the iron lost after donating.
• You cannot get AIDS or any other infectious disease by donating blood.
• 5 liters of blood in the body of an average adult.
• One unit of whole blood is roughly the equivalent of 4,75 ml.
• Blood makes up about 7 percent of your body's weight.
• A newborn baby has about one cup of blood in his body.
• Giving blood will not decrease your strength.
• Any company, community organization, place of worship or individual may contact their local community blood center to host a blood drive.
• People who donate blood are volunteers and are not paid for their donation

How to donate blood



Make an Appointment
Ø  It always helps us to know in advance when you are coming in to make a donation.

Hydrate
Ø  Be sure to drink plenty of fluids the day of your donation.

Wear Something Comfortable
Ø  Wear clothing with sleeves that can easily be rolled up above the elbow

Maintain a Healthy Level of Iron in Your Diet before Donating
Ø  If possible, include iron-rich foods in your diet, especially in the weeks before your donation.

Bring a List of Medications You Are Taking
Ø  The blood bank staff may need to know about any prescription and/or over the counter medications that may be in your system.

Bring an ID
Ø  Please bring either your donor card, driver's license or two other forms of identification.

Bring a Friend
Ø  Bring along a friend, so that you may both enjoy the benefits of giving blood.

No Tension - feel relax!
Ø  Blood donation is a simple and very safe procedure so there is nothing to worry about.

The Donation Process Step by Step – International standards

Donating blood is a simple thing to do, but it can make a big difference in the lives of others. The donation process from the time you arrive until the time you leave takes about an hour. The donation itself is only about 8-10 minutes on average. 

The steps in the process are

Step 1: Registration

• Ø  The Blood bank staff and volunteers will sign you in and go over basic eligibility and donation information.
• Ø  You will read information about donating blood, and will be asked to show a donor card, driver's license, or other form(s) of ID.

Step 2: Health History & Mini-Physical

• Ø  You will answer some questions during a private and confidential interview about your health history and places you have traveled.
• Ø  The Blood bank staff will check your temperature, pulse, blood pressure and hemoglobin level present in a sample of blood.

Step 3: The Donation

• Ø  The Blood bank staff  will cleanse an area on your arm and insert a brand new sterile needle for the blood draw. This feels like a quick pinch and is over in seconds.
• Ø  The actual donation takes about 8-10 minutes, during which you will be seated comfortably. Certain donation types, such as platelets, red cells or plasma (aphaeresis donations) can take up to 2 hours.
• Ø  When approximately a pint of blood has been collected, the donation is complete and a staff person will place a bandage on your arm.

Step 4: Refreshments

• Ø  After donating, you should have a snack and something to drink in the refreshments area. You can leave the site after 10-15 minutes and continue with your normal daily activities.
• Ø  Enjoy the feeling of accomplishment knowing that you have helped save lives 

         

What to do after your donation

Hydrate More

• ü  You should continue to drink water throughout the day of your donation.

Avoid Heavy Lifting or Exercise

• ü  Try not to exert yourself too much for the rest of the day.

Accept  Blood Bank staffs  Most Sincere Thank You!

• ü  Also accept the thanks of people whose lives were changed by blood donations.

Enjoy the feeling of knowing that you helped save lives!

Why blood is vital even for the dying

Everyone knows blood is literally a lifesaver for those who’ve been in an accident or need it to help survive treatments and operations. But for some, whose illness has no cure and that last battle they face just can’t be won, a blood transfusion can help to improve their quality of life during their final months, weeks or even days.

"These vital transfusions give patients a better quality of life. It gives them the energy and ability to enjoy this precious, final time with their families."

But this time is often a gift that only blood can provide. In some serious accidents, its use can mean that a critically ill patient can stay alive long enough for their loved ones to reach the hospital to see them, one last time.

How Blood banks use Blood?

Whole blood

• ·         This is rarely used these days, only really in instances of severe blood loss. It's usually separated into its individual components.

Red cells

• ·         The main function of red blood cells is to distribute oxygen to body tissues and to carry waste carbon dioxide back to the lungs.
• ·         These are used in the treatment of all kinds of anaemia which can't be medically corrected, such as when rheumatoid arthritis or cancer is involved, when red cells break down in the newborn and for sickle cell disease.
• ·         They're also essential to replace lost red cells due to blood loss in accidents, surgery and after childbirth.

Platelets

• ·         Platelets can be used in bone marrow failure, post transplant and chemotherapy treatments, and leukemia. Platelets can be of huge benefit to the recipient.

Plasma

• ·         Fresh frozen plasma is used after obstetric loss of blood (which is usually childbirth), during cardiac surgery, and to reverse any anti-coagulant treatment.
• ·         It's also used to replace clotting factors after massive transfusions or when they are not being sufficiently produced, such as liver disease.
• ·         And then there's processed plasma, which has several important uses.
• ·         For instance, it is used in the treatment of haemophilia and for treating sufferers of Christmas disease, a life-threatening form of haemophilia.
• ·         Processed plasma is also used to help produce stronger antibodies against diseases like tetanus, hepatitis, chickenpox and rabies.
• ·         It also helps generate anti-D, which is used for RhD negative pregnant women carrying RhD positive babies.
• ·         Additionally there is a protein called albumin contained in plasma, which is extremely beneficial for burn victims.

Misconceptions and Fear about blood donation

"I am afraid to give blood"

• ü  For everything there is a first time. Just have courage and try it once. You will wonder why you ever hesitated.

"Other people must be giving enough blood"

• ü  That's an assumption! If everyone takes this stand, what will happen to people in dire need of blood?

"My blood is not the right type"

• ü  Every type is the "right type". Both rare and common types are needed all the time.

"They wouldn't want my blood because of illness I've had"

• ü  If you have doubts, the staff on duty will review your medical history with you.

"I don't have any blood to spare"

• ü  If you are healthy, you have enough blood. You can regularly donate every 3 months without any problem.

"My blood isn't rich enough"

• ü  A sample of your blood is checked before you donate. If you are found unfit at least you know the cause and can correct it.

"I am afraid of being turned down"

• ü  If you are medically deferred, that's okay, at least you tried. You can try again later. The need for blood never runs out.

"You'll take too much and I'll feel weak"

• ü  The amount taken is less than one pint and replaced within a few hours by your body. You can continue your usual activities after donation.

"I am too busy"

• ü  This is positively the lousiest excuse ever! You can make the time, if you really want to.

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