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> Facts about Blood
HIGHLIGHTS OF TRANSFUSION MEDICINE
HISTORY
Who needs blood?
The need for blood is great. Blood transfusions often are needed
for trauma victims - due to accidents and burns - heart surgery, organ
transplants, and patients receiving treatment for leukemia, cancer or
other diseases, such as sickle cell disease and thalassemia. And with an
aging population and advances in medical treatments and procedures
requiring blood transfusions, the demand for blood continues to increase.
Who donates blood?
To be eligible to donate blood, a person must be in good health and
generally must be at least 18 years of age (although in some cases younger
people are permitted to donate blood, with parental consent.)
What are the criteria for blood donation?
Minimum weight requirements may vary among facilities, but generally,
donors must weigh at least 45 kgs Most blood banks have no upper age
limit. All donors must pass the physical and health history examinations
given prior to donation.
The donor's body replenishes the fluid lost from donation in 24 hours. It
may take up to two months to replace the lost red blood cells. Whole blood
can be donated once every eight weeks (56 days).
Who should not donate blood?
Anyone who has ever used intravenous drugs (illegal IV drugs)
Hemophiliacs
Anyone with a positive antibody test for HIV (AIDS virus)
Anyone who has had hepatitis
Anyone who has/has had cancer
Anyone who has risk factors for HBS Ag,HCV,VDRL,Maleria.
Where is blood donated?
Blood donations should be made only at licensed blood banks, Voluntary
blood donation camps conducted by recognized organizations and at
hospital-based donor centers. You may contact CCT or find out from the
official CCT web site, information about the conduct of blood donation
camps in a place near to you.
What are the constituents of each unit of blood ?
Typically, each donated unit of blood, referred to as whole blood, is
separated into multiple components, such as red blood cells, plasma,
platelets, and cryoprecipitated AHF (antihemophilic factor). Presently CCT
collects and provides whole blood only. However in the near future, CCT
proposes to possess technology for a State of the Art Components Unit and
provide blood components too. Each blood component can be transfused to a
different individual, each with different needs.
What tests are performed on
donated blood?
After blood has been drawn, it is tested for ABO group (blood type) and Rh
type (positive or negative), as well as for any unexpected red blood cell
antibodies that may cause problems in a recipient. Screening tests also
are performed for evidence of donor infection with hepatitis B and C
viruses, human immunodeficiency viruses HIV-1 and HIV-2, human T-lymphotropic
viruses HTLV-I and HTLV-II, and syphilis.
The specific tests currently performed are listed below:
Hepatitis B surface antigen (HBsAg)
Hepatitis B core antibody (anti-HBc)
Hepatitis C virus antibody (anti-HCV)
HIV-1 and HIV-2 antibody (anti-HIV-1 and anti-HIV-2)
Serologic test for syphilis
What kind of precautions are
taken while collecting blood?
Besides conducting all relevant medical tests to ascertain the eligibility
of individual donors’ , blood is collected in the utmost hygienic
conditions using disposable blood bags, ,needles and syringes under the
supervision of qualified lab technicians.
How is blood stored and used?
Each unit of whole blood normally is stored under refrigeration for a
maximum of 42 days,
What fees are associated with blood?
While donated blood is free, there are significant costs associated with
collecting, testing, preparing components, labeling, storing and shipping
blood; recruiting and educating donors; and quality assurance. As a
result, processing fees are charged to recover costs.
for further details check POLICY.
What is the availability of blood?
The blood supply level fluctuates throughout the year. For example, after
the Kargil war or Gujarat earth quake blood supply swelled to very high
levels, due to the overwhelming response of donors but otherwise is very
scarce to obtain.
What can you do if you aren’t eligible to donate?
While a given individual may be unable to donate, he or she may be able to
recruit a suitable donor. Blood banks are always in need of volunteers to
assist at blood draws or to organize blood donation camps.
Is there any recognition for the donors?
Donor cards and Appreciation Certificates are given to each of the
voluntary blood donors. Besides Blood will be provided free of cost to the
kith and kin of the Donor when in need. Persons who donate blood at least
4 times in a year through Chiranjeevi Eye & Blood Bank , any of CCT’s
Voluntary blood donation clubs will receive a letter of appreciation
through the hands of Chiranjeevi.
What is the most common blood type?
The approximate distribution of blood types in the
population is as follows.
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In an emergency, anyone can receive type O red
blood cells, and type AB individuals can receive red blood cells of any
ABO type. Therefore, people with type O blood are known as “universal
donors,” and those with type AB blood are known as “universal
recipients.” In addition, AB plasma donors can give to all blood types.
WHOLE BLOOD AND BLOOD COMPONENTS
Background
Blood may be transfused as whole blood or as one of its components.
Because patients seldom require all of the components of whole blood, it
makes sense to transfuse only that portion needed by the patient for a
specific condition or disease. This treatment, referred to as "blood
component therapy," allows several patients to benefit from one unit of
donated whole blood. Blood components include red blood cells, plasma,
platelets, and cryoprecipitated antihemophilic factor (AHF). Up to four
components may be derived from one unit of blood.
Whole blood is a living tissue that
circulates through the heart, arteries, veins, and capillaries carrying
nourishment, electrolytes, hormones, vitamins, antibodies, heat, and
oxygen to the body's tissues. Whole blood contains red blood cells, white
blood cells, and platelets suspended in a fluid called plasma.
If blood is treated to prevent clotting and permitted to stand in a
container, the red blood cells, which weigh more than the other
components, will settle to the bottom; the plasma will stay on top; and
the white blood cells and platelets will remain suspended between the
plasma and the red blood cells. A centrifuge may be used to hasten this
separation process. The platelet-rich plasma is then removed and placed
into a sterile bag, and it can be used to prepare platelets and plasma or
cryoprecipitated AHF. To obtain platelets, the platelet-rich plasma is
centrifuged, causing the platelets to settle at the bottom of the bag.
Plasma and platelets are then separated and made available for
transfusion. The plasma also may be pooled with plasma from other donors
and further processed, or fractionated, to provide purified plasma
proteins such as albumin, immunoglobulin (IVIG), and clotting factors.
Red blood cells
are perhaps the most recognizable component of whole blood. Red blood
cells contain hemoglobin, a complex iron-containing protein that carries
oxygen throughout the body and gives blood its red color. The percentage
of blood volume composed of red blood cells is called the "hematocrit."
The average hematocrit in an adult male is 47 percent. There are about one
billion red blood cells in two to three drops of blood, and, for every 600
red blood cells, there are about 40 platelets and one white cell.
Manufactured in the bone marrow, red blood cells are continuously being
produced and broken down. They live for approximately 120 days in the
circulatory system and are eventually removed by the spleen.
Red blood cells are prepared from whole blood by removing the plasma, or
the liquid portion of the blood. They can raise the patient's hematocrit
and hemoglobin levels while minimizing an increase in volume.
Patients who benefit most from transfusions of red blood cells include
those with chronic anemia resulting from disorders such as kidney failure,
malignancy, 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
have congestive heart failure or who are elderly or debilitated; these
patients might not tolerate the increased volume provided by whole blood.
Improvements in cell preservative solutions over the last 15 years have
increased the shelf life of red blood cells from 21 to 42 days. Red blood
cells may be treated and frozen for extended storage (up to 10 years).
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. Plasma is usually not used for transfusion purpose but is
fractionated (separated) into specific products such as albumin, specific
clotting factor concentrates and IVIG (intravenous immune globulin).
Fresh frozen plasma is plasma frozen within hours after donation in order
to preserve clotting factors, stored for one to seven years, and thawed
before it is transfused. It 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 also can be used for plasma
replacement via a process called plasma exchange.
Cryoprecipitated AHF
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. It may also be used as hemostatic
preparation [fibrin sealant or fibrin glue in surgery.
Platelets (or thrombocytes) are very
small cellular components of blood that help the clotting process by
sticking to the lining of blood vessels. 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 massive blood loss resulting from trauma,
as well as 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 also may 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 used to treat a condition called
thrombocytopenia, in which there is a shortage of platelets, and in
patients with abnormal platelet function. Platelets are stored at room
temperature for up to five days.
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 immune defense.
Granulocytes can be collected by apheresis or by centrifugation of whole
blood. They are transfused within 24 hours after collection and are used
for infections that are unresponsive to antibiotic therapy. The
effectiveness of white blood cell transfusion is still being investigated.
Plasma derivatives
are concentrates of specific plasma proteins that are prepared from pools
(many units) of plasma. Plasma derivatives are obtained through a process,
known as fractionation, developed during World War II, and are
heat-treated and/or solvent detergent-treated to kill certain viruses,
including HIV and hepatitis B and C. Plasma derivatives include:
-
Factor VIII Concentrate
-
Factor IX Concentrate
-
Anti-Inhibitor
Coagulation Complex (AICC)
-
Albumin
-
Immune Globulins,
including Rh Immune Globulin
-
Anti-Thrombin III
Concentrate
-
Alpha 1-Proteinase
Inhibitor Concentrate
HIGHLIGHTS OF TRANSFUSION MEDICINE HISTORY
1628 : English physician William Harvey
discovers the circulation of blood. Shortly afterward, the earliest known
blood transfusion is attempted.
1665: The first recorded successful blood
transfusion occurs in England: Physician Richard Lower keeps dogs alive by
transfusion of blood from other dogs.
1667 : Jean-Baptiste Denis in France and
Richard Lower in England separately report successful transfusions from
lambs to humans. Within 10 years, transfusing the blood of animals to
humans becomes prohibited by law because of reactions.
1795: In Philadelphia, American physician
Philip Syng Physick, performs the first human blood transfusion, although
he does not publish this information.
1818: James Blundell, a British obstetrician,
performs the first successful transfusion of human blood to a patient for
the treatment of postpartum hemorrhage. Using the patient's husband as a
donor, he extracts approximately four ounces of blood from the husband's
arm and, using a syringe, successfully transfuses the wife. Between 1825
and 1830, he performs 10 transfusions, five of which prove beneficial to
his patients, and publishes these results. He also devises various
instruments for performing transfusions and proposed rational indications.
1840: At St. George's School in London,
Samuel Armstrong Lane, aided by consultant Dr. Blundell, performs the
first successful whole blood transfusion to treat hemophilia.
1867: English surgeon Joseph Lister uses
antiseptics to control infection during transfusions.
1873-1880: US physicians transfuse milk (from
cows, goats, and humans).
1884: Saline infusion replaces milk as a
“blood substitute” due to the increased frequency of adverse reactions to
milk.
1900 : Karl Landsteiner, an Austrian
physician, discovers the first three human blood groups, A, B, and C.
Blood type C was later changed to O. His colleagues Alfred Decastello and
Adriano Sturli add AB, the fourth type, in 1902. Landsteiner receives the
Nobel Prize for Medicine for this discovery in 1930.
1907: Hektoen suggests that the safety of
transfusion might be improved by cross matching blood between donors and
patients to exclude incompatible mixtures. Reuben Ottenberg performs the
first blood transfusion using blood typing and crossmatching in New York.
Ottenberg also observed the mendelian inheritance of blood groups and
recognized the “universal” utility of group O donors.
1908: French surgeon Alexis Carrel devises a
way to prevent clotting by sewing the vein of the recipient directly to
the artery of the donor. This vein-to-vein or direct method, known as
anatomists, is practiced by a number of physicians, among them J.B. Murphy
in Chicago and George Crile in Cleveland. The procedure proves unfeasible
for blood transfusions, but paves the way for successful organ
transplantation, for which Carrel receives the Nobel Prize in 1912.
1908 Mores chi describes the ant globulin
reaction. The ant globulin is a direct way of visualizing an
antigen-antibody reaction that has taken place but is not directly
visible. The antigen and antibody react with each other, then, after
washing to remove any unbound antibody, the ant globulin reagent is added
and binds between the antibody molecules that are stuck onto the antigen.
This makes the complex big enough to see.
1912: Roger Lee, a visiting physician at the
Massachusetts General Hospital, along with Paul Dudley White, develops the
Lee-White clotting time. Adding another important discovery to the growing
body of knowledge of transfusion medicine, Lee demonstrates that it is
safe to give group O blood to patients of any blood group, and that blood
from all groups can be given to group AB patients. The terms "universal
donor" and "universal recipient" are coined.
1914: Long-term anticoagulants, among them
sodium citrate, are developed, allowing longer preservation of blood.
1915: At Mt. Sinai Hospital in New York,
Richard Lewisohn uses sodium citrate as an anticoagulant to transform the
transfusion procedure from direct to indirect. In addition, Richard Weil
demonstrates the feasibility of refrigerated storage of such
anticoagulated blood. Although this is a great advance in transfusion
medicine, it takes 10 years for sodium citrate use to be accepted.
1916: Francis Rous and J.R.Turner introduce a
citrate-glucose solution that permits storage of blood for several days
after collection. Allowing for blood to be stored in containers for later
transfusion aids the transition from the vein-to-vein method to indirect
transfusion. This discovery also allows for the establishment of the first
blood depot by the British during World War I. Oswald Robertson, an
American Army officer, is credited with creating the blood depots.
Robertson received the AABB Landsteiner Award in 1958 as developer of the
first blood bank.
1927-1947 The MNSs and P systems are
discovered. MNSs and P are two more blood group antigen systems - just as
ABO is one system and Rh is another.
1939/40: The Rh blood group system is
discovered by Karl Landsteiner, Alex Wiener, Philip Levine, and R.E.
Stetson and is soon recognized as the cause of the majority of transfusion
reactions. Identification of the Rh factor takes its place next to the
discovery of ABO as one of the most important breakthroughs in the field
of blood banking.
1940: Edwin Cohn, a professor of biological
chemistry at Harvard Medical School, develops cold ethanol fractionation,
the process of breaking down plasma into components and products. Albumin,
a protein with powerful osmotic properties, plus gamma globulin and
fibrinogen are isolated and become available for clinical use. John
Elliott develops the first blood container, a vacuum bottle extensively
used by the Red Cross.
1941: Isodor Ravdin, a prominent surgeon from
Philadelphia, effectively treats victims of the Pearl Harbor attack with
Cohn's albumin for shock. Injected into the blood stream, albumin absorbs
liquid from surrounding tissues, preventing blood vessels from collapsing,
a finding associated with shock.
1943: The introduction by J.F. Loutit and
Patrick L. Mollison of acid citrate dextrose (ACD) solution, which reduces
the volume of anticoagulant, permits transfusions of greater volumes of
blood and permits longer term storage.
1943: P. Beeson publishes the classic
description of transfusion-transmitted hepatitis.
1945: Coombs, Mourant, and Race describe the
use of antihuman globulin (later known as the “Coombs Test”) to identify
“incomplete” antibodies.
1950 : Audrey Smith reports the use of
glycerol cryoprotectant for freezing red blood cells.
1950: In one of the single most influential
technical developments in blood banking, Carl Walter and W.P. Murphy, Jr.,
introduce the plastic bag for blood collection. Replacing breakable glass
bottles with durable plastic bags allows for the evolution of a collection
system capable of safe and easy preparation of multiple blood components
from a single unit of whole blood. Development of the refrigerated
centrifuge in 1953 further expedites blood component therapy.
Mid-1950s: In response to the heightened
demand created by open-heart surgery and advances in trauma care patients,
blood use enters its most explosive growth period.
1959: Max Perutz of Cambridge University
deciphers the molecular structure of hemoglobin, the molecule that
transports oxygen and gives red blood cells their color.
1960 : A. Solomon and J.L. Fahey report the
first therapeutic plasmapheresis procedure - a procedure that separates
whole blood into plasma and red blood cells.
1961: The role of platelet concentrates in
reducing mortality from hemorrhage in cancer patients is recognized.
1962 : The first antihemophilic factor (AHF)
concentrate to treat coagulation disorders in hemophilia patients is
developed through fractionation.
1964 : Plasmapheresis is introduced as a
means of collecting plasma for fractionation.
1965 : Judith G. Pool and Angela E. Shannon
report a method for producing Cryoprecipitated AHF for treatment of
hemophilia.
1967: Rh immune globulin is commercially
introduced to prevent Rh disease in the newborns of Rh-negative women.
1969: S. Murphy and F. Gardner demonstrate
the feasibility of storing Platelets at room temperature, revolutionizing
platelet transfusion therapy.
1970: Blood banks move toward an
all-volunteer blood donor system.
1971 : Hepatitis B surface antigen (HBsAg)
testing of donated blood begins.
1972 : Apheresis is used to extract one
cellular component, returning the rest of the blood to the donor.
1979 : A new anticoagulant preservative,
CPDA-1, extends the shelf life of whole blood and red blood cells to 35
days, increasing the blood supply and facilitating resource sharing among
blood banks.
Early 1980s: With the growth of component
therapy, products for coagulation disorders, and plasma exchange for the
treatment of autoimmune disorders, hospital and community blood banks
enter the era of transfusion medicine, in which doctors trained
specifically in blood transfusion actively participate in patient care.
1981: First Acquired Immune Deficiency
Syndrome (AIDS) case reported.
1983: Additive solutions extend the shelf
life of red blood cells to 42 days.
1984: Human Immunodeficiency Virus (HIV)
identified as cause of AIDS
1985: The first blood-screening test to
detect HIV is licensed and quickly implemented by blood banks to protect
the blood supply.
1987 : Two tests that screen for indirect
evidence of hepatitis are developed and implemented, hepatitis B core
antibody (anti-HBc) and the alanine aminotransferase test (ALT).
1989 : Human-T-Lymphotropic-Virus-I-antibody
(anti-HTLV-I) testing of donated blood begins.
1990: Introduction of first specific test for
hepatitis C, the major cause of “non-A, non-B” hepatitis.
1992 : Testing of donor blood for HIV-1 and
HIV-2 antibodies (anti-HIV-1 and anti-HIV-2) is implemented.
1996 : HIV p24 antigen testing of donated
blood begins. Although the test does not completely close the HIV window,
it shortens the window period.
2002 : West Nile virus identified as
transfusion transmissible.
ion.
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