LabCE blood bank terms
A ficin (enzyme) treated panel can be a useful tool for determining the identity of an antibody. On a ficin-treated panel, reactions with what systems are enhanced, while reactions with what other systems are degraded and reactions with what stay the same (unaffected).
(Rh, Lewis, Kidd) (MN, Duffy) (Kell)
How would one prepare 3 mL of a 5% albumin working solution from a stock 30% albumin solution?
0.5 mL stock 30% albumin + 2.5 mL diluent. (% stock solution) x (V1) = (% working solution) x (v2) v1= volume of the stock solution v2= volume of the working solution Then: (30) x (v1) = (5) x (3 mL) 30 v1= 15 mL V1= 15 mL /30 = 0.5 mL T he total volume of working solution that is needed is 3 mL.
If an average-weight adult male patient with a 7 gram/dL hemoglobin is given two units of packed cells, what would be the approximate new hemoglobin value (assuming there is no active bleeding or other predisposing factors that would shorten the survival of the blood cells)?
9.0 gm/dL
When a unit of packed RBC's is split using the open system, each half-unit must be issued within:
24 hours
A 300 microgram does of RhIg can suppress immunization to how many militers of D-positive whole blood.
30 mL
In order to prevent a loss of viability in platelet concentrates during storage the pH must be maintained above:
6.2. 300 cc donor plasma is collected into an apheresis platelet bag, and 50 cc into a whole blood platelet bag. This keeps the acceptable pH. Platelets keep this way for 5 days and once pooled reduces to 4 hours from the time pooled.
Which one of these physical exam results would cause a donor to be deferred? A weight of 120lbs a pules of 75 a diastolic blood pressure of 110 mm Hg A temperature of 99.3F
A diastolic blood pressure of 110 mm Hg. Diastolic pressure should be no higher than 100 mm Hg.
The majority of anti-Lea antibodies are of which immunoglobulin class?
IgM
Match substances secreted with their respective blood groups: A, B, & H B &H A & H H
AB, B, A, and O
Match the appropriate genotype to its corresponding phenotype: AB, O, A, B
AB, OO, AA,AO, AND BB, BO
The most severe acute hemolytic transfusion reactions are the result of which of the following: Rh incompatibility ABO incompatibility Cold agglutinins delayed hypersensitivity
ABO incompatiblility
Autologous blood must be tested for what before transfusion:
ABO, Rh
Which of the following serological test results may occur in a patient experiencing a hemolytic transfusion reaction due to antibodies such as anti-c and anti-K? (select all that apply): Patients antibody strength may initially decrease Patient may develop a positive DAT with mixed field agglutination Patient's antibody becomes undetectable Patients antibody increases in titer weeks later
All are possible. The patients antibody strength can initially decrease due to adsorbing to transfused antigen-positive donor red cells. This results in a positive DAT with mixed-field agglutination, since only the transfused donor cells are antibody-sensitized. The patients antibody may even become undetectable at the stage when most of it has adsorbed to the donor cells. Eventually, the patient's antibody increases in strength. This may become apparent weeks later, depending on the relative amount of antibody compared to donor red cells present in the patients circulation
Which of the following antibodies is detected primarily in the antiglobulin phase of the crossmatch: Anti-Fya Anti-M Anti-B Anti-P1
Anti-Fya. The duffy system consists of Fya and Fyb. Antibodies to these antigens are IgG and are detected in the antiglobulin phase. Anti-M, Anti-B and Anti-P1 are typically IgM antibodies and may agglutinate saline suspended cells at room temperature.
The two or three reagent cells used for antibody screening will detect which of the following: Antibodies to red cell A and B antigens Antibodies to most white cell antigens Antibodies to common alloantigens Antibodies to most private (low incidence) red cell antigens
Antibodies to common alloantigens. Screening cells are group O, and will, of course not detect antibodies to A and B antigens. Private antigens are low incidence, and screening cells are unlikely to be positive for them.
All of the following are benefits of autologous donation except: Reduces exposure to infectious agents Are always on hand in case of an unexpected emergency Reduces demand for homologous blood Eliminates sensitization to cellular blood components
Are always on hand in case of an unexpected emergency. Autologous units must be drawn before they are needed, and must be readily available, therefore are generally not of use in emergencies.
What procedure will increase the platelet concentration in the preparation of platelets?
Centrifuge the blood at a low speed, remove the plasma and spin the plasma again at a high speed.
FFP should be used for what deficiencies:
Coagulation deficiencies. FFP should be sued to treat coagulation deficiencies-though the levels of factors V and VIII are usually decreased in FFP units. FFP is not used for platelet replacement as there are virtually no platelets in FFP units. FFP should never be used as a volume expander, unless traumatic bleeding is taking place. Finally, FFP is not used to replace albumin in recipients.
What is the most common reagent source for Anti-A1 (a reagent that is used to differentiate subgroup A1 from subgroup A2)?
Dolichos Biflorous seeds
A severe hemophiliac, with a factor VIII activity of less than 1% is actively bleeding due to a serious car accident. The blood product of choice is:
Factor VIII concentrate. This will aid in the coagulation process to cease active bleeding in the patient.
Hemoglobinuria and hemoglobinemia will be present in reactions where there is extravascular hemolysis. T or F
False. In intravascular hemolysis, there is no release of free hemoglobin, and therefore no hemoglobinemia or hemoglobinuria. Sensitized red cells are removed from circulation by the monocytes and macrophages in reticuloendothelial system.
Lewis antigen is a human blood group unlike most others. The antigen is produced and secreted by exocrine glands, eventually adsorbing to the surface of red blood cells. Its expression is based on the genetic expression of the Lewis and Secretor genes. Based on the following information, predict the Lewis Antigen phenotypic expression based on the following genotype: (lele) (Se)
Le (a-b-) A person with a nonfunctional Lewis gene (lele) and functional Secretor gene (Se) expresses the phenotype Le (a-b-). The key to answering this question and all others like it, is simply memorizing the secretor chart. Essentially, a functional Lewis gene codes for the enzyme fucosyltransferase 3, which adds fucose to an oligosaccharide precursor at the penultimate position. Meanwhile, a functional Secretor gene codes for the enzyme fucosyltransferase 2, which adds fucose to an oligosaccharide precursor at the terminal position. If a person has Le expression but is a nonsecretor (sese), he will express a phenotype of Le (a+b-). If a person has Le expression and is also a secretor (Se), he will express a phenotype of Le (a-b+). If a person does not have Le expression (lele), it does not matter if he is a secretor (Se) or nonsecretor (sese), he will always express the phenotype Le (a-b-).
In HDN what antigen-antibody reaction is occurring?
Maternal antibody against fetal antigen. In hemolytic disease of the newborn (hdn), maternal antibodies are directed against fetal red blood cells. This condition can cause red cell lysis in the infant and can be dangerous for the health of the fetus.
Bacterial contamination is MOST likely in which of the following blood products? Red Blood Cells Red Blood Cells Frozen Platelets Fresh Frozen Plasma
Platelets
What is his MOST likely phenotype for a white male who has the following Rh antigens: C, c, D, E, e?
R1= DCe, R2= DcE Most likely phenotype is R1R2
What is the MOST likely explanation for the following results: anti-A= 1+ anti-B= negative A1 cells= 1+ B cells= 4+
Subgroup of A with anti-A1`
What is the MOST common infective agent to be transmitted through blood transfusion that results in morbidity and mortality?
The most common infectious agent to be transmitted through blood transfusion is bacteria. The estimated risk of blood components with bacteria is 1 in 5000 platelet units and 1 in 30000 red blood cell units. For this reason, the inspections of red blood cell units that are done upon receipt of blood from a supplier, immediately before use, and at defined intervals must include a check for abnormal appearance. comparison of a bag and segment color should be performed for red blood cell units to aid in detection of bacterially contaminate units. storing red blood cells above 6 C may promote the growth of bacteria. Platelets that are stored at 20-24 C are particular concern. It is a requirement that platelet components be tested to detect the presence of bacteria. The risk of transmission of HIV through blood transfusion is 1 in 2 million in the USA. The statistics from Canada and Europe show this risk to be about the same or less. HAV is normally transmitted through the feco-oral route but rarely can be transmitted through blood. The FDA recommends that donors who have a history of malaria be deferred from donation for 3 years after becoming asymptomatic and for one year following return from an area where malaria is endemic. The initial interview of donors has made the transmission of malarial parasites through blood transfusion a rarity.
Evaluating B-type natriuretic peptide (BNP) levels can be helpful in distinguishing transfusion-related acute lung injuries (TRALI) from cardiopulmonary edemas. T or F
True. It is important to rule out cardiac causes of pulmonary edema. One way of differentiating is evaluating the BNP level, which is known to be elevated in congestive heart failure and not TRALI.
All of the following criteria for donor RBC to be used for an exchange transfusion relate to both ABO HDFN and HDFN due to anti-D: 1. Less than or equal to 7 days old (or fresher) 2. Reconstituted with AB FFP 3. CMV negative 4. Negative for hemoglobin S 5. Irradiated
True. The listed criteria apply to donor RBC for exchange transfusions to treat any type of HDFN, including those caused by antibodies outside the ABO and Rh blood group systems.
To detect the presence of blocking antibodies fixed on the red cells of a newborn infant:
Use the direct antiglobulin test
An O pos patient has no reactions at immediate spin but both screen cells are positive and all antibody panel cells are reacting 1+ at AHG. The auto control is 1+. What would you suspect to be the cause.
Warm autoantibody. There is no reaction at the immediate spin phase so the cold autoantibody can be eliminated. Reactivity is occurring at AHG with all panel cells and the auto control is positive which can indicate a warm autoantibody. An elution may be beneficial to determine if other clinically significant antibodies are present or to help identify the warm autoantibody.
What is the most prudent step to follow to select units for cross-match after recipient antibodies have been identified?
antigen type patient cells and any donor cells to be cross-matched. After any significant antibodies have been identified, the technologist must antigen type any blood cell units for the recipient along with a cross-match to prevent transfusion reactions.
What additional information is required on a label or tie tag of an autologous unit?
identification of the recipient must be included on the label or tie tag of an autologous unit. Then name of the ordering physician may be included, but is not required. The location of the collection site is not required on the label. The statement that is required on the label for an autologous unit is "For Autologous Use Only"
