Blood Transfusion

Blood transfusion is the taking of blood or blood-based products from one individual and transferring them into the circulatory system of another. It can be considered as a form of organ transplant. Blood transfusions may treat medical conditions, such as massive blood loss due to trauma, surgery, shock and where the red cell producing mechanism fails.

Great care is taken to ensure that the recipient's immune system will not attack the donor blood, and also to avoid transfusing white blood cells that could initiate an immune attack on the host (graft versus host disease). Nevertheless, blood transfusion does suppress the immune system, increasing the risk of complications after surgery.

Possible complications in a recipient include:

• Febrile reactions
• Hemolytic reactions
• Allergic reactions
• Infection
• Fluid overload
• Acute respiratory distress syndrome specifically transfusion-related acute lung injury (TRALI)
• Transfusion-associated graft versus host disease (TA-GVHD)

Blood Substitutes and Products:

Sometimes only parts of the blood are taken for donation. Blood is made up mostly of plasma, red blood cells, white blood cells and platelets. Plasma and platelets can be donated separately in a process called apheresis. Blood is usually separated into components after being donated to make the most use of it. Donation of whole blood is generally reserved for treating young children and remote areas where the hospital summons donors when it needs them. Resulting blood component products also include albumin protein used to treat burns, clotting factor concentrates used to treat hemophilia, cryoprecipitate, fibrinogen concentrate, and immunoglobulin antibodies for immunological disorders.

Rather than using whole blood transfusions, doctors are now increasingly using individual blood components to treat the patients. Some of these blood products are mentioned below.

Whole Blood-Whole Blood contains one unit of plasma and cells. Whole blood can be stored normally for five weeks.

Red Blood Cells (RBCs)-One unit of red Blood cells (RBC) contains approximately 180 ml of red cells and approximately 30 ml of plasma. Red blood cells are indicated for patients with symptomatic anemia that is not treatable with specific therapy such as iron, vitamin B12 or with folic acid.

Washed Red Blood Cells-Washed red blood cells are red blood cells washed with normal saline to remove most of the plasma. Washed red cells can used in patients who have had repeated hypersensitivity reactions to blood or components despite prophylactic administration of antihistamines.

Leukoreduced Red Blood Cells-Leukoreduced red blood cell units contain leukocytes in a specifically reduced amount. Leukoreduced red cells are usually effective in preventing non-hemolytic febrile transfusion reactions for most patients and prevention of CMV transmission.

Pediatric/Divided RBC Units-Divided red blood cell units are indicated for infants who require small amounts of red cells.

Platelets-Platelets are cells essential for the coagulation of blood. Platelet products contain plasma, red cells and white cells (leukocytes). Platelet transfusions are indicated for patients with bleeding from thrombocytopenia or platelet dysfunction.

Granulocytes (Neutrophils)-Granulocytes are obtained by an apheresis procedure. Granulocytes are considered for patients with severe neutropenia with life-threatening bacterial or fungal infection not responsive to antibiotic therapy.

Fresh Frozen Plasma (FFP)-is the plasma removed from a unit of whole blood and frozen at or below 55° Fahrenheit within eight hours of collection. FFP contains all coagulation factors in normal amounts and is free of red cells, leukocytes and platelets. It is indicated for patients with coagulation factor deficiencies.

Cryoprecipitate (CRYO)-is a concentrate of three hemostatic proteins prepared from donated whole blood. A single bag of Cryo contains an average of 100 units of factor VIII and von Willebrand factor and 150 to 250 mg of fibrinogen with some factor XIII and fibronectin. No compatibility testing is required and ABO-Rh type is not relevant. It is indicated for bleeding or imminent invasive procedures for patients with significant hypofibrinogenemia.

Factor VIII Concentrate-Factor VIII concentrates are a commercially prepared, lyophilized powder purified from human plasma to treat patients with hemophilia A or von Willebrand’s disease.

Antithrombin III-Antithrombin III concentrates are commercially purified from human plasma pools and lyophilized.

Below is a list of some abbreviations used frequently in relation to hematological diseases, blood, blood products and blood transfusion.

Abbr. Form	Full meaning
2,3-DPG	2,3-dishospyhoglycerate
ACT	Activated Clotting Time
ADH	Antidiuretic Hormone
AHG	Antihuman Globulin
AIDS	Acquired Immune Deficiency Syndrome
ALT	Alanine Aminotransferase
ANA	Antinuclear Antibody
ANH	Acute Normovolemic Hemodilution
anti-HBc	Antibody to Hepatitis B Core Antigen
anti-HCV	Antibody to Hepatitis C Virus
anti-HTLV-I/II	Antibody to Human T-cell lymphotropic virus type I/II
aPPT	Activated Partial Thromboplastin Time
ARDS	Acute Respiratory Distress Syndrome
AST	Aspartate Transaminase
CHD	Coronary Heart Disease
CMV	Cytomegalovirus
CPD	Citrate, Phosphate, Dextrose solution
CPDA-1	Citrate, Phosphate, Dextrose-Adenine solution
C/T	Crossmatch-to-Transfusion ratio (C:T)
DDAVP	1-Desamino-8-D-Arginine Vasopressin
DIC	Disseminated Intravascular Coagulopathy
EACA	epsilon-aminocaproic Acid
FDA	Food and Drug Administration
FFP	Fresh Frozen Plasma
FNHTR	Febrile Nonhemolytic Transfusion Reaction
GGTP	Gamma Glutamyl Transferase (GGT)
GHVD	graft-versus-host Disease
HAM	HTLV-1-associated Myelopathy
HBsAg	Hepatitis B Surface Antigen
HB	Hemoglobin
HCT	Hematocrit
HBV	Hepatitis B Virus
HCV	Hepatitis C Virus
HDN	Hemolytic Disease of the Newborn
HH	Hemochromatosis (distinguish from H&H)
HIV	Human Immunodeficiency Virus
HLA	Human Leukocyte Antigen
HTLV-I/II	Human T-cell Lymphotropic Virus type I/II
IAD	Intraoperative Autologous Donation
IgA	Immunoglobulin A
ITP	Idiopathic Thrombocytopenic Purpura
LD	Lactate Dehydrogenase
MCH	Mean Corpuscular Hemoglobin
MCHC	Mean Corpuscular Hemoglobin Concentrate
MCV	Mean Corpuscular Volume
mg/dL	milligrams per deciliter
MPV	Mean Platelet Volume
PPF	Purified Protein Fraction
PRP	platelet-rich Plasma
PT	Prothrombin Time
PTP	Posttransfusion Purpura
PTT	Partial Thromboplastin Time
RBCs	Red Blood Cells
Rh	Rhesus Factor
STS	Serological Test for Syphilis
T&S	Type and Screen
TA-GVHD	transfusion-associated graft-versus-host disease
TSH	Thyroid Stimulating Hormone
TSP	Tropical Spastic Paraparesis
TSE	Transmissible Spongiform Encephalopathies
TTP	Thrombotic Thrombocytopenic Purpura
TTTS	Twin to Twin Transfusion Syndrome
WBCs	White Blood Cells
vWd	von Willebrand's Disease
vWf	von Willebrand's Factor

Blood Transfusion and Substitutes