Whole blood
Encyclopedia
Whole blood is a term used in transfusion medicine
for human blood
from a standard blood donation
. The blood is typically combined with an anticoagulant
during the collection process, but is generally otherwise unprocessed. In the US, the capitalized "Whole Blood" means a specific standardized product for transfusion or further processing, where "whole blood" is any unmodified collected blood.
as whole blood without further processing. Most blood banks now split the whole blood into two or more components, typically red blood cells and a plasma
component such as Fresh Frozen Plasma
. Platelets for transfusion can also be prepared from a unit of whole blood. Some blood banks have replaced this with platelets collected by plateletpheresis
because whole blood platelets, sometimes called "random" platelets, must be pooled from multiple donors to get enough for a therapeutic dose.
The collected blood is generally separated into components by one of three methods. A centrifuge can be used in a "hard spin" which separates whole blood into plasma and red cells or for a "soft spin" which separates it into plasma, buffy coat (used to make platelets), and red blood cells. The third method is sedimentation: the blood simply sits overnight and the red cells and plasma are separated by gravity.
(TACO), a potentially dangerous complication.
Whole blood is sometimes "recreated" from stored red blood cells and fresh frozen plasma
(FFP) for neonatal transfusions. This is done to provide a final product with a very specific hematocrit (percentage of red cells) with type O
red cells and type AB
plasma to minimize the chance of complications.
If the blood will be used to make platelets, it is kept at room temperature until the process is complete. This must be done quickly to minimize the warm storage of RBCs in the unit.
Transfusion medicine
Transfusion medicine is the branch of medicine that is concerned with the transfusion of blood and blood components. The blood bank is the section of the clinical laboratory where medical technologists process and distribute blood products under the supervision of a medical director, often...
for human blood
Blood
Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....
from a standard blood donation
Blood donation
A blood donation occurs when a person voluntarily has blood drawn and used for transfusions or made into medications by a process called fractionation....
. The blood is typically combined with an anticoagulant
Anticoagulant
An anticoagulant is a substance that prevents coagulation of blood. A group of pharmaceuticals called anticoagulants can be used in vivo as a medication for thrombotic disorders. Some anticoagulants are used in medical equipment, such as test tubes, blood transfusion bags, and renal dialysis...
during the collection process, but is generally otherwise unprocessed. In the US, the capitalized "Whole Blood" means a specific standardized product for transfusion or further processing, where "whole blood" is any unmodified collected blood.
Processing
Historically, blood was transfusedBlood transfusion
Blood transfusion is the process of receiving blood products into one's circulation intravenously. Transfusions are used in a variety of medical conditions to replace lost components of the blood...
as whole blood without further processing. Most blood banks now split the whole blood into two or more components, typically red blood cells and a plasma
Blood plasma
Blood plasma is the straw-colored liquid component of blood in which the blood cells in whole blood are normally suspended. It makes up about 55% of the total blood volume. It is the intravascular fluid part of extracellular fluid...
component such as Fresh Frozen Plasma
Fresh frozen plasma
The term fresh frozen plasma refers to the liquid portion of human blood that has been frozen and preserved after a blood donation and will be used for blood transfusion...
. Platelets for transfusion can also be prepared from a unit of whole blood. Some blood banks have replaced this with platelets collected by plateletpheresis
Plateletpheresis
Plateletpheresis is the process of collecting thrombocytes, more commonly called platelets, a component of blood involved in blood clotting...
because whole blood platelets, sometimes called "random" platelets, must be pooled from multiple donors to get enough for a therapeutic dose.
The collected blood is generally separated into components by one of three methods. A centrifuge can be used in a "hard spin" which separates whole blood into plasma and red cells or for a "soft spin" which separates it into plasma, buffy coat (used to make platelets), and red blood cells. The third method is sedimentation: the blood simply sits overnight and the red cells and plasma are separated by gravity.
Transfusion
Whole blood has similar risks to a transfusion of red blood cells and must be cross-matched to avoid hemolytic transfusion reactions. Most of the indications for use are identical to those for RBCs, and whole blood is not used because the extra plasma can contribute to transfusion associated circulatory overloadTransfusion associated circulatory overload
In transfusion medicine, Transfusion associated circulatory overload is a blood transfusion condition that occurs due to a rapid transfusion of a large volume of blood.-Symptoms:...
(TACO), a potentially dangerous complication.
Whole blood is sometimes "recreated" from stored red blood cells and fresh frozen plasma
Fresh frozen plasma
The term fresh frozen plasma refers to the liquid portion of human blood that has been frozen and preserved after a blood donation and will be used for blood transfusion...
(FFP) for neonatal transfusions. This is done to provide a final product with a very specific hematocrit (percentage of red cells) with type O
Abo
Abo may refer to:* ABO blood group system, a human blood type and blood group system** ABO , enzyme encoded by the ABO gene that determines the ABO blood group of an individual* Abo of Tiflis , an Arab East Orthodox Catholic saint...
red cells and type AB
Abo
Abo may refer to:* ABO blood group system, a human blood type and blood group system** ABO , enzyme encoded by the ABO gene that determines the ABO blood group of an individual* Abo of Tiflis , an Arab East Orthodox Catholic saint...
plasma to minimize the chance of complications.
Storage
Whole blood is typically stored under the same conditions as red blood cells and can be kept up to 35 days if collected with CPDA-1 storage solution or 21 days with other common storage solutions such as CPD.If the blood will be used to make platelets, it is kept at room temperature until the process is complete. This must be done quickly to minimize the warm storage of RBCs in the unit.
External links
- Circular of Information for Blood Products from U.S. Food and Drug AdministrationFood and Drug AdministrationThe Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
(FDA)