Q:* *What is blood? How much blood does a person have?* *A:* Blood is the
red coloured fluid flowing continuously in our body's circulatory system.
About 1/12th of the body weight of a healthy individual is blood. On an
average there are about 5 - 6 litres of blood present.
------------------------------
*Q:* *What is the composition of blood?* *A:* Blood contains mainly a fluid
called plasma in which are suspended cellular elements. Three types of cells
- Red Blood Cells or RBC's, White Blood Cells or WBC's and tiny platelets
form the cellular element.
------------------------------
*Q:* *What are the functions of these components?* *A:* *(a) Plasma: *Acts
as a vehicle to carry many substances like glucose, fats, and proteins,
enzymes, and hormones etc., in addition to the blood cells.
*(b)** Red Cells: *Carry oxygen from lungs to various body tissues and take
back carbon dioxide from the cells and tissues to be thrown out of body in
the form of exhaled air.
*(c**) White cells: *Mainly act as body scavengers and guards. They help in
the immune system of the body and act as defence forces of the body killing
the bacteria or any other organisms entering the body.
*(d)** Platelets: *Help in the clotting and coagulation of blood. We have
experienced in our life that whenever we get injured the bleeding stops
after a few minutes. This is brought about by a mechanism called clotting of
blood in which platelets plays a very vital role.
------------------------------
*Q:* *How is blood formed?* *A:* Blood consists of RBCs, WBCs, platelets
suspended in plasma. In early embryonic life blood cells are formed in liver
and spleen. But by the fifth month the Haemopoisis (i.e., formation of
blood.) occurs in bone marrow and lymphatic tissues. At birth the entire
bone marrow is red and active. Gradually as the child grows, the marrow
remains red only in the flat bones and vertebrae. The RBC, grannulocytes of
WBC and platelets are produced mainly by bone marrow. The lymphocytes,
monocytes, plasma cells are formed in the lymphoid and Reticulo Endothelial
tissues. The orderly proliferation of the cells in the bone marrow and their
release into circulation is carefully regulated according to the needs of
body. Every day, new blood cells are being produced in the bone marrow and
every day old cells are dying and being removed from the body.
Red blood cells have a life of 120 days and when it becomes old and senile
it is thrown out. White cells live for a few days and platelets for a few
hours. Thus daily new cells are added to the circulation and old are removed
from it.
------------------------------
*Q:* *What is haemoglobin?* *A:* Haemoglobin is a substance present in the
red cells. It is helpful in carrying oxygen and carbon dioxide. On an
average, in a healthy male it should be between 14 - 16 gm % and in a female
it should be about 12 - 14 gm %. This is also being daily synthesized and
the new is replacing the old stock.
------------------------------
*Q:* *What are blood groups?* *A:* Every individual has two types of blood
groups. The first is called the ABO - grouping and the second type is called
Rh - grouping.
In the ABO - group there are four categories namely A Group, B Group, O
Group and AB Group.
In the Rh - Group either the individual is Rh-positive, or Rh-negative. Rh
is a factor called as Rhesus factor that has come to us from Rhesus monkeys.
Thus each and very human being will fall in one of the following groups.
*A positive or A negative
B positive or B negative
O positive or O negative
AB positive or AB negative *
There are also some sub groups as well as a few other classifications.
------------------------------
*Q:* *What is the importance of knowing the blood groups?* *A:* For all
practical and routine purposes, it is ideal to transfuse to the patient the
same group of blood which he belongs to. It is only under very dire
emergency that we take O group as universal donor and AB groups as universal
recipient. Under no circumstances O group can get any other blood except O.
Similarly A group patient cannot be given B group blood and vice versa.
------------------------------
*Q:* *Why is A group not given B group blood?* *A:* This is due to the
reason that, the blood of A Group people contains anti - B antibodies. In B
group people there are anti - An antibodies. If we give A group blood to a B
group patient, it is bound to be incompatible and will result in serious
consequences.
------------------------------
*Q:* *Why are Rh negative and Rh positive incompatible?* *A:* A patient
with Rh-negative blood cannot be given Rh-positive blood as the
antigen-antibody REACTIONS WILL RESULT IN SEVERE consequences.
In cases where a woman has Rh negative and her husband has Rh positive, the
first child with Rh positive may be normal. But subsequently the woman may
not conceive or may have repeated abortions. There may be intra uterine
fetal death. If the child born is alive, it will suffer from a fatal disease
called "Erythroblastosis Foetalis". Now mothers can be given an injection of
anti-D within 24 hours of the delivery of a Rh-positive child and thus
protect the next baby from this catastrophe.
------------------------------
*Q:* *What is a unit of blood?* *A:* Blood is collected in plastic bags
which contain a watery fluid which prevents blood from getting coagulated.
On an average we draw about 450 ml. of blood from a person, depending on the
weight of the donor. This blood, plus the amount of anti coagulant present
in the bottle or bag, is known as one unit of blood.
------------------------------
*Q:* *Can blood of animals be transfused to human beings?* *A:* Scientists
have tried a lot but so far they are not successful. Only the blood of a
human being can be transfused to a human patient.
------------------------------
*Q:* *How long can blood be stored?* *A:* Whole blood can be stored up to
35 days, when kept in CPDA anti coagulant solution and refrigerated at 2 - 4
deg C. But the demand is so great that blood hardly ever remains in storage
for so long and is used much before expiry.
------------------------------
*Q:* *Can we separate blood into its components?* *A:* Yes! Now with
technical advancements, we can make components of blood and store them. For
example, plasma can be separated from whole blood and stored up to one year
in frozen state at -80 deg C temperature or below. This is called Fresh
Frozen Plasma. Similarly there are other components like Platelet Rich
Plasma; Platelet Concentrate (can be stored as a life saving measure upto 5
days now at 22- 24 degrees C in a platelet incubator and agitator);
Cryoprecipitate (which is very useful in treating bleeding disorders due to
the deficiency of factor VIII and IX); Factor VIII and IX; Albumin, Globulin
and many others.
In most progressive blood banks more than 85 % of the blood collected is
converted into components and stored. This is because many patients do not
require whole blood. For example, a patient whose hemoglobin is low and is
therefore anemic, may just require Packed Cells i.e. only red cells; a
patient with burns may need more of plasma than cells; a patient with
hemophilia may require only Factor VIII.
Now with the advent of Cell-separators we can directly draw a particular
component from the donor, while rest of the blood constituents go back to
the donor.
red coloured fluid flowing continuously in our body's circulatory system.
About 1/12th of the body weight of a healthy individual is blood. On an
average there are about 5 - 6 litres of blood present.
------------------------------
*Q:* *What is the composition of blood?* *A:* Blood contains mainly a fluid
called plasma in which are suspended cellular elements. Three types of cells
- Red Blood Cells or RBC's, White Blood Cells or WBC's and tiny platelets
form the cellular element.
------------------------------
*Q:* *What are the functions of these components?* *A:* *(a) Plasma: *Acts
as a vehicle to carry many substances like glucose, fats, and proteins,
enzymes, and hormones etc., in addition to the blood cells.
*(b)** Red Cells: *Carry oxygen from lungs to various body tissues and take
back carbon dioxide from the cells and tissues to be thrown out of body in
the form of exhaled air.
*(c**) White cells: *Mainly act as body scavengers and guards. They help in
the immune system of the body and act as defence forces of the body killing
the bacteria or any other organisms entering the body.
*(d)** Platelets: *Help in the clotting and coagulation of blood. We have
experienced in our life that whenever we get injured the bleeding stops
after a few minutes. This is brought about by a mechanism called clotting of
blood in which platelets plays a very vital role.
------------------------------
*Q:* *How is blood formed?* *A:* Blood consists of RBCs, WBCs, platelets
suspended in plasma. In early embryonic life blood cells are formed in liver
and spleen. But by the fifth month the Haemopoisis (i.e., formation of
blood.) occurs in bone marrow and lymphatic tissues. At birth the entire
bone marrow is red and active. Gradually as the child grows, the marrow
remains red only in the flat bones and vertebrae. The RBC, grannulocytes of
WBC and platelets are produced mainly by bone marrow. The lymphocytes,
monocytes, plasma cells are formed in the lymphoid and Reticulo Endothelial
tissues. The orderly proliferation of the cells in the bone marrow and their
release into circulation is carefully regulated according to the needs of
body. Every day, new blood cells are being produced in the bone marrow and
every day old cells are dying and being removed from the body.
Red blood cells have a life of 120 days and when it becomes old and senile
it is thrown out. White cells live for a few days and platelets for a few
hours. Thus daily new cells are added to the circulation and old are removed
from it.
------------------------------
*Q:* *What is haemoglobin?* *A:* Haemoglobin is a substance present in the
red cells. It is helpful in carrying oxygen and carbon dioxide. On an
average, in a healthy male it should be between 14 - 16 gm % and in a female
it should be about 12 - 14 gm %. This is also being daily synthesized and
the new is replacing the old stock.
------------------------------
*Q:* *What are blood groups?* *A:* Every individual has two types of blood
groups. The first is called the ABO - grouping and the second type is called
Rh - grouping.
In the ABO - group there are four categories namely A Group, B Group, O
Group and AB Group.
In the Rh - Group either the individual is Rh-positive, or Rh-negative. Rh
is a factor called as Rhesus factor that has come to us from Rhesus monkeys.
Thus each and very human being will fall in one of the following groups.
*A positive or A negative
B positive or B negative
O positive or O negative
AB positive or AB negative *
There are also some sub groups as well as a few other classifications.
------------------------------
*Q:* *What is the importance of knowing the blood groups?* *A:* For all
practical and routine purposes, it is ideal to transfuse to the patient the
same group of blood which he belongs to. It is only under very dire
emergency that we take O group as universal donor and AB groups as universal
recipient. Under no circumstances O group can get any other blood except O.
Similarly A group patient cannot be given B group blood and vice versa.
------------------------------
*Q:* *Why is A group not given B group blood?* *A:* This is due to the
reason that, the blood of A Group people contains anti - B antibodies. In B
group people there are anti - An antibodies. If we give A group blood to a B
group patient, it is bound to be incompatible and will result in serious
consequences.
------------------------------
*Q:* *Why are Rh negative and Rh positive incompatible?* *A:* A patient
with Rh-negative blood cannot be given Rh-positive blood as the
antigen-antibody REACTIONS WILL RESULT IN SEVERE consequences.
In cases where a woman has Rh negative and her husband has Rh positive, the
first child with Rh positive may be normal. But subsequently the woman may
not conceive or may have repeated abortions. There may be intra uterine
fetal death. If the child born is alive, it will suffer from a fatal disease
called "Erythroblastosis Foetalis". Now mothers can be given an injection of
anti-D within 24 hours of the delivery of a Rh-positive child and thus
protect the next baby from this catastrophe.
------------------------------
*Q:* *What is a unit of blood?* *A:* Blood is collected in plastic bags
which contain a watery fluid which prevents blood from getting coagulated.
On an average we draw about 450 ml. of blood from a person, depending on the
weight of the donor. This blood, plus the amount of anti coagulant present
in the bottle or bag, is known as one unit of blood.
------------------------------
*Q:* *Can blood of animals be transfused to human beings?* *A:* Scientists
have tried a lot but so far they are not successful. Only the blood of a
human being can be transfused to a human patient.
------------------------------
*Q:* *How long can blood be stored?* *A:* Whole blood can be stored up to
35 days, when kept in CPDA anti coagulant solution and refrigerated at 2 - 4
deg C. But the demand is so great that blood hardly ever remains in storage
for so long and is used much before expiry.
------------------------------
*Q:* *Can we separate blood into its components?* *A:* Yes! Now with
technical advancements, we can make components of blood and store them. For
example, plasma can be separated from whole blood and stored up to one year
in frozen state at -80 deg C temperature or below. This is called Fresh
Frozen Plasma. Similarly there are other components like Platelet Rich
Plasma; Platelet Concentrate (can be stored as a life saving measure upto 5
days now at 22- 24 degrees C in a platelet incubator and agitator);
Cryoprecipitate (which is very useful in treating bleeding disorders due to
the deficiency of factor VIII and IX); Factor VIII and IX; Albumin, Globulin
and many others.
In most progressive blood banks more than 85 % of the blood collected is
converted into components and stored. This is because many patients do not
require whole blood. For example, a patient whose hemoglobin is low and is
therefore anemic, may just require Packed Cells i.e. only red cells; a
patient with burns may need more of plasma than cells; a patient with
hemophilia may require only Factor VIII.
Now with the advent of Cell-separators we can directly draw a particular
component from the donor, while rest of the blood constituents go back to
the donor.
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