Blood Administration ATI
Blood Basics
Notes
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
, Blood Administration ATI
either a 5% or 25% solution. Each is comprised of fractionated albumin
Notes
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
have hemophilia, to correct low fibrinogen levels, and to treat von
Notes
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
Blood Basics
Notes
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
, Blood Administration ATI
either a 5% or 25% solution. Each is comprised of fractionated albumin
Notes
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
have hemophilia, to correct low fibrinogen levels, and to treat von
Notes
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
