Blood Administration ATI Notes
Blood Basics
Blood is a living tissue that is composed of a variety of cells suspended in a watery fluid
called plasma. Its function is to circulate through the heart, arteries, veins, and capillaries,
carrying nourishment, vitamins, electrolytes, hormones, antibodies, warmth, and oxygen
to the body’s tissues and transporting wastes and carbon dioxide to excretory organs.
Blood is a chemical, a fluid, and a temperature regulator. The cellular components of the
blood – red blood cells, white blood cells, and platelets – comprise 45% of its total volume.
The remaining 55% is plasma. Approximately 7% to 10% of an adult’s body weight is
blood.
Whole blood is used exactly as it is received from the donor. It contains the various blood
components: red blood cells, white blood cells, plasma, platelets, clotting factors, and
immunoglobulins. Because the use of whole blood has a greater effect on fluid volume
than any of the components does, it is used only when needed or when individual blood
components are not available. Whole blood is generally transfused only when a patient
loses a large amount of blood.
Blood-component therapy is based on separating or “fractionating” whole blood into its
cellular and plasma components. Because patients seldom need all the components of
whole blood, it is medically wise to transfuse only the component needed to manage the
specific disorder or disease. Blood-component therapy allows several patients to benefit
from one unit of donated whole blood, a more efficient use of the blood supply.
Red blood cells, also called erythrocytes, contain hemoglobin, a complex iron-containing
protein that carries oxygen throughout the body and gives blood its red color. Red blood
cells are produced in the bone marrow, live for about 120 days in the circulatory system,
and are eventually broken down by the spleen. Red cells raise hematocrit and hemoglobin
levels without significantly increasing blood volume. They are recovered from whole blood
after donation by removing the plasma portion of the blood. Often referred to as “packed
red blood cells,” this component is transfused to restore or maintain adequate organ
oxygenation. Indications for red blood cell transfusion include anemia due to neoplastic
blood disease, conditions that affect red blood cell production, sickle-cell anemia, blood
loss due to trauma, surgical blood loss, and to offset some of the effects of chemotherapy.
Packed red blood cells are kept refrigerated at a specific temperature and are viable for 42
days but may be frozen for extended storage up to 10 years.
Plasma, the liquid portion of the blood, is composed of about 92% water and 7% plasma
proteins. Plasma contains albumin, fibrinogen, globulins, and other clotting proteins. In
addition to maintaining blood pressure and providing essential proteins, plasma serves as
the medium for the cellular exchange of vital minerals and electrolytes and for the
elimination of cellular waste products. Fresh frozen plasma is obtained by centrifuging
whole blood and freezing it within hours after donation. Plasma is used to treat bleeding
and coagulation disorders, to replace fluid volume for patients with massive burns and for
those with liver failure, and to replace platelet-aggregating inhibitors in patients who have
thrombocytopenic purpura or hemolytic uremic syndrome. Plasma can be kept frozen for
up to 1 year. Once thawed, it must be transfused within 24 hours.
One fractionated product of plasma is the protein albumin, essential for maintaining blood
volume and blood pressure. Albumin is prepared in either a 5% or 25% solution. Each is
comprised of fractionated albumin from multiple, or “pooled” donors.
Immune globulin, a concentrated solution of the antibody IgG, is prepared from large pools
of plasma. The intravenous (IV) form, IVIG, is used to replace inadequate amounts of IgG
for patients at risk for recurrent bacterial infections, such as those with chronic leukemia.
Unlike other components, IVIG remains viable when subjected to 10 hours of 140° F (60°
C) heat, which eliminates viral contamination.
Cryoprecipitate antihemophilic factor, sometimes referred to simply as “cryo,” is a
component prepared by slowly thawing frozen plasma and recovering the precipitate,
which contains coagulation factors VIII and XIII, fibrinogen, von Willebrand factor
(VIII/vWF), and fibronectin. It is transfused to prevent or control bleeding in people who
, Blood Administration ATI Notes
have hemophilia, to correct low fibrinogen levels, and to treat von Willebrand disease and
other clotting disorders. These small volumes are typically freeze-dried and must be
reconstituted prior to transfusion via a syringe.
Platelets are a cellular component that helps the clotting process by sticking to the lining
of blood vessels. They are extracted from plasma by centrifugation, but it usually takes
several units of whole blood to obtain enough platelets for adequate treatment. Another
option is apheresis or plateletpheresis, a process that involves the use of special
equipment to separate a donor’s blood components. It centrifuges and extracts platelets
while returning red cells and plasma to the donor’s circulation. Platelets are usually pooled
from up to 10 patients and are infused over 15 to 30 minutes. They are transfused to treat
thrombocytopenia and platelet-function abnormalities.
Granulocytes are prepared by apheresis collection or centrifugation of whole blood and
should be infused over 45 to 60 minutes. Granulocytes are a type of white blood cell used
to treat unresponsive infections in patients with low granulocyte counts and as supportive
therapy for patients undergoing chemotherapy for some types of leukemia.
An important concept to understand before learning to give a blood transfusion is how
blood is grouped. Blood groups are determined by the inheritance of certain genes, one
set from each parent. They are expressed as the presence or absence of certain antigens
on the red blood cell membranes.
The most important blood group for transfusion purposes is the ABO system. It includes
the A, B, O, and AB blood types, each based on the presence or absence of the A and B
antigens. Type A blood has the A antigen, type B has the B antigen, type AB has both, and
type O has neither. The recipient’s blood type determines compatibility with donor blood
types, based on the presence or absence of A and B antigens and antibodies.
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,” while those with type AB blood are known as “universal recipients.” In
addition, AB plasma donors can give to all blood types.
Also, important, especially in perinatal care, is the Rhesus, or Rh system. Blood is
classified according to the presence or the absence of the major D antigen on the surface
of the red blood cells. A person who has the D antigen is classified Rh-positive; a person
who does not have the D antigen is Rh-negative. Rh-negative individuals may donate to
Rh-positive recipients but should only receive Rh-negative blood to prevent the formation
of anti-D antibodies.
When a Rh-negative woman is exposed to D antigens, anti-D antibodies develop. Exposure
to D-antigens can occur through a previous Rh-positive transfusion, previous pregnancy,
or, under certain conditions, a current pregnancy with a Rh-positive fetus. The anti-D
antibodies can attack the red blood cells of subsequent Rh-positive fetuses, resulting in
erythroblastosis fetalis, a hemolytic (red blood cell-destroying) disorder that is potentially
fatal for the fetus. It is common practice to perform Rh antibody testing during pregnancy
and to administer Rho(D) Immune Globulin (RhoGAM) at 28 weeks of gestation and at
delivery to prevent the formation of Rh-positive antibodies. RhoGAM contains antibodies
against Rh antigens on fetal blood cells. When given to an exposed mother, RhoGAM
Blood Basics
Blood is a living tissue that is composed of a variety of cells suspended in a watery fluid
called plasma. Its function is to circulate through the heart, arteries, veins, and capillaries,
carrying nourishment, vitamins, electrolytes, hormones, antibodies, warmth, and oxygen
to the body’s tissues and transporting wastes and carbon dioxide to excretory organs.
Blood is a chemical, a fluid, and a temperature regulator. The cellular components of the
blood – red blood cells, white blood cells, and platelets – comprise 45% of its total volume.
The remaining 55% is plasma. Approximately 7% to 10% of an adult’s body weight is
blood.
Whole blood is used exactly as it is received from the donor. It contains the various blood
components: red blood cells, white blood cells, plasma, platelets, clotting factors, and
immunoglobulins. Because the use of whole blood has a greater effect on fluid volume
than any of the components does, it is used only when needed or when individual blood
components are not available. Whole blood is generally transfused only when a patient
loses a large amount of blood.
Blood-component therapy is based on separating or “fractionating” whole blood into its
cellular and plasma components. Because patients seldom need all the components of
whole blood, it is medically wise to transfuse only the component needed to manage the
specific disorder or disease. Blood-component therapy allows several patients to benefit
from one unit of donated whole blood, a more efficient use of the blood supply.
Red blood cells, also called erythrocytes, contain hemoglobin, a complex iron-containing
protein that carries oxygen throughout the body and gives blood its red color. Red blood
cells are produced in the bone marrow, live for about 120 days in the circulatory system,
and are eventually broken down by the spleen. Red cells raise hematocrit and hemoglobin
levels without significantly increasing blood volume. They are recovered from whole blood
after donation by removing the plasma portion of the blood. Often referred to as “packed
red blood cells,” this component is transfused to restore or maintain adequate organ
oxygenation. Indications for red blood cell transfusion include anemia due to neoplastic
blood disease, conditions that affect red blood cell production, sickle-cell anemia, blood
loss due to trauma, surgical blood loss, and to offset some of the effects of chemotherapy.
Packed red blood cells are kept refrigerated at a specific temperature and are viable for 42
days but may be frozen for extended storage up to 10 years.
Plasma, the liquid portion of the blood, is composed of about 92% water and 7% plasma
proteins. Plasma contains albumin, fibrinogen, globulins, and other clotting proteins. In
addition to maintaining blood pressure and providing essential proteins, plasma serves as
the medium for the cellular exchange of vital minerals and electrolytes and for the
elimination of cellular waste products. Fresh frozen plasma is obtained by centrifuging
whole blood and freezing it within hours after donation. Plasma is used to treat bleeding
and coagulation disorders, to replace fluid volume for patients with massive burns and for
those with liver failure, and to replace platelet-aggregating inhibitors in patients who have
thrombocytopenic purpura or hemolytic uremic syndrome. Plasma can be kept frozen for
up to 1 year. Once thawed, it must be transfused within 24 hours.
One fractionated product of plasma is the protein albumin, essential for maintaining blood
volume and blood pressure. Albumin is prepared in either a 5% or 25% solution. Each is
comprised of fractionated albumin from multiple, or “pooled” donors.
Immune globulin, a concentrated solution of the antibody IgG, is prepared from large pools
of plasma. The intravenous (IV) form, IVIG, is used to replace inadequate amounts of IgG
for patients at risk for recurrent bacterial infections, such as those with chronic leukemia.
Unlike other components, IVIG remains viable when subjected to 10 hours of 140° F (60°
C) heat, which eliminates viral contamination.
Cryoprecipitate antihemophilic factor, sometimes referred to simply as “cryo,” is a
component prepared by slowly thawing frozen plasma and recovering the precipitate,
which contains coagulation factors VIII and XIII, fibrinogen, von Willebrand factor
(VIII/vWF), and fibronectin. It is transfused to prevent or control bleeding in people who
, Blood Administration ATI Notes
have hemophilia, to correct low fibrinogen levels, and to treat von Willebrand disease and
other clotting disorders. These small volumes are typically freeze-dried and must be
reconstituted prior to transfusion via a syringe.
Platelets are a cellular component that helps the clotting process by sticking to the lining
of blood vessels. They are extracted from plasma by centrifugation, but it usually takes
several units of whole blood to obtain enough platelets for adequate treatment. Another
option is apheresis or plateletpheresis, a process that involves the use of special
equipment to separate a donor’s blood components. It centrifuges and extracts platelets
while returning red cells and plasma to the donor’s circulation. Platelets are usually pooled
from up to 10 patients and are infused over 15 to 30 minutes. They are transfused to treat
thrombocytopenia and platelet-function abnormalities.
Granulocytes are prepared by apheresis collection or centrifugation of whole blood and
should be infused over 45 to 60 minutes. Granulocytes are a type of white blood cell used
to treat unresponsive infections in patients with low granulocyte counts and as supportive
therapy for patients undergoing chemotherapy for some types of leukemia.
An important concept to understand before learning to give a blood transfusion is how
blood is grouped. Blood groups are determined by the inheritance of certain genes, one
set from each parent. They are expressed as the presence or absence of certain antigens
on the red blood cell membranes.
The most important blood group for transfusion purposes is the ABO system. It includes
the A, B, O, and AB blood types, each based on the presence or absence of the A and B
antigens. Type A blood has the A antigen, type B has the B antigen, type AB has both, and
type O has neither. The recipient’s blood type determines compatibility with donor blood
types, based on the presence or absence of A and B antigens and antibodies.
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,” while those with type AB blood are known as “universal recipients.” In
addition, AB plasma donors can give to all blood types.
Also, important, especially in perinatal care, is the Rhesus, or Rh system. Blood is
classified according to the presence or the absence of the major D antigen on the surface
of the red blood cells. A person who has the D antigen is classified Rh-positive; a person
who does not have the D antigen is Rh-negative. Rh-negative individuals may donate to
Rh-positive recipients but should only receive Rh-negative blood to prevent the formation
of anti-D antibodies.
When a Rh-negative woman is exposed to D antigens, anti-D antibodies develop. Exposure
to D-antigens can occur through a previous Rh-positive transfusion, previous pregnancy,
or, under certain conditions, a current pregnancy with a Rh-positive fetus. The anti-D
antibodies can attack the red blood cells of subsequent Rh-positive fetuses, resulting in
erythroblastosis fetalis, a hemolytic (red blood cell-destroying) disorder that is potentially
fatal for the fetus. It is common practice to perform Rh antibody testing during pregnancy
and to administer Rho(D) Immune Globulin (RhoGAM) at 28 weeks of gestation and at
delivery to prevent the formation of Rh-positive antibodies. RhoGAM contains antibodies
against Rh antigens on fetal blood cells. When given to an exposed mother, RhoGAM
