Hematology - CBC Flashcards
Which blood type can receive anyone’s blood (universal recipient)?
AB+
Which blood type can be given to anyone (universal donor)?
O-
What is cross matching?
Done before a transfusion to catch antigens that are not routinely typed
Ensure the donor RBCs match recipient’s serum
A small amount of recipient serum is mixed with a small amount of donor RBCs
Examined under the microscope
Agglutination indicates incompatibility
Direct Coombs’ Test
Test the fetal RBCs (cord blood) using anti-human globulin to bind anti-RhD antibodies on the surface of these fetal RBCs that have crossed the placental blood barrier
Diagnoses Hemolytic Disease of the Newborn (HDN)
Indirect Coombs’ Test
Tests for anti-RhD antibodies in the birth parent’s serum
Used to identify and prevent possible HDN in future pregnancies if the first born is Rh+ and there is a possible fetal-maternal blood transfusion
Types of Transfusion Products
Whole Blood
Packed Red Cells
Leukocyte-Poor RBC
Platelet Concentrates
Granulocyte Concentrates
Fresh Frozen Plasma
Factor Concentrates
Packed RBC
most commonly used blood product; 1 unit can increase a patient’s hematocrit by 3-5%
Whole blood is spun down, and plasma removed; packed = hematocrit is now 70-80%
Indications:
O2 deprivation
Profoundly fatigued due to anemia
Kidney not synthesizing adequate EPO
Improper bone marrow function
Leukocyte-poor RBC
WBC removed to reduce transfusion reactions – contains no HLA molecules
Immunogenic HLA molecules can induce chills and fever
Receiving products with WBC may develop memory cells and increase risk if future transfusion is needed
Indications:
Patient has had 2 documented febrile reactions
Patient may require multiple transfusions
Patient may require a transplant
Transfusion reaction examples?
Transfusion reactions
Hemolytic transfusion reaction due to RBC-antibody reaction
Febrile non-hemolytic transfusion reaction
Transfusion-associated acute lung injury
Prevent with Type & Crossmatch (ABO and Rh)
Blood-borne Pathogens / Infectious Diseases – HIV, Hep B & C, Malaria
Allergic Anaphylaxis – WBC-mediated febrile reactions
Circulatory overload
Religious objections to blood transfusion
Alternatives to transfusion
Autologous Transfusions
No risk alloimmunization or infectious disease
Best with elective surgery – patient would donate before surgery for use during surgery
Directed Transfusions
Solicit donations from family/friends – blood will still be screened
Thought to be safer than anonymous transfusion products but not necessarily
platelet concentrations
One bag contains platelets from 4-6 donors of the same blood type and is only viable for 5 days
Indications:
Thrombocytopenia
Platelet dysfunction
Chemotherapy
Contraindications:
Disseminated Intravascular Coagulation (DIC) – quick depletion of platelets due to excessive clotting
Idiopathic Thrombocytopenic Purpura (ITP) – immune system attacks platelets
fresh frozen plasma
Contains all coagulation factors in normal amounts
Free of RBCs, WBCs, and Platelets
Indication: documented coagulation factor deficiencies who are actively bleeding OR who are about to undergo an invasive surgery
Must be ABO compatible with the recipient
Rh type does not need to be considered
Factor concentrates
Most commonly administered blood factors are:
Factor VIII Concentrates – commercially prepared, lyophilized powder purified from human plasma to treat Hemophilia A or von Willebrand Disease (VWD)
Factor IX Concentrates – commercially prepared, lyophilized powder purified from human plasma to treat Hemophilia B
Current preparation process and screening eliminate risk of HIV, HBV and HCV transmission
Recombinant (synthetic) human factors is purified from genetically engineered non-human cells grown in tissue culture.
Recombinant von Willebrand Factor was approved by FDA in 2018
Leukocytosis
infections, sepsis, cancers, drug reaction, etc.
Leukopenia
viral infections, overwhelming bacterial infections, chemo/radiation, bone marrow failure
Critical values
Critical values:
Below 0.5 x 10E3/uL - extremely dangerous and often fatal
Below 2.0 x 10E3/uL
Above 30.0 x 10E3/uL
Neutrophils
- most numerous
- bacterial infections * important for inflammation
- immature form is called “band cells” refers to nucleus not yet segmented.
Neutrophil clinical significance
Neutrophilia: acute bacterial infections, inflammation, tissue necrosis
Neutropenia: an acute overwhelming bacterial infection (poor prognosis), viral infections (mono, hepatitis, measles, etc), cytotoxic/immunosuppressive drugs, organic solvents, nutritional deficiencies (folate, B12, copper)
Reference value: 50-70%
0-5% are band cells
Lymphocytes
Migrate to areas of inflammation in both early and late stages
Produce serum immunoglobulins
Plays an important role in immunologic reaction/response
All lymphocytes are made in the bone marrow
Clinical significance of Lymphocytes
Lymphocytosis: leukemia, viral infections (CMV, EBV, HIV, hepatitis)
Lymphopenia: chemo, lymphoma, steroid use, aplastic anemia, AIDS
Reference value: 30-45%
Lymphocytes
B Cells: mature in bone marrow
Regulates antigen-antibody response that is specific to the offending antigen; remembers offending antigens
Fully differentiated B cells = plasma cells, produces antibodies (in bone marrow and inflamed tissues only)
T Cells: mature in thymus
CD4+ helper T cells, natural killer T cells, CD8+ suppressor T cells, cytotoxic T cells
Eosinophils
Primary used to diagnose allergic reactions and (large) parasitic infections
Monitor severity and treatment efficacy
Granules contain histamines
Clinical significance: increased in allergies, hay fever, asthma, parasitic infections (those that invade tissues, like worms), chronic skin diseases and inflammatory bowel diseases (Crohn’s and Ulcerative Colitis)
Reference value: 0-3%
Monocytes
Largest cells of normal blood
Second line of defense against infection by phagocytosing injured and dead cells, microorganisms, and insoluble particles from circulating blood (scavenger for debris)
Produces interferon
Clinical Significance:
Increased: > 600/uL in bacterial infections, TB, subacute bacterial endocarditis, and syphilis
Reference value: 0-6%
Basophils
Least numerous WBCs
With granules that contain heparin, histamines, and serotonin
Clinical significance:
Increased: basophilic leukemia, Hodgkin’s lymphoma
May be implicated in IgG mediated anaphylaxis due to allergens
Decreased: hyperthyroidism
Reference value: 0-1%
