CCCC Clinical Study Guide Flashcards
What antibodies have been implicated in HDFN?
ABORh, Kell, Duffy (uncommon), Kidd, anti-S, anti-s, anti-U, anti-M (in IgG form; this is rare)
What antibodies have been implicated in HTR?
Kell, Duffy, Kidd, anti-S, anti-s, anti-U, rare form of anti-P1 reactive at 37 degrees
How can cold agglutinins be excluded from testing?
perform the antibody screen (and panel is necessary) using the prewarm technique
How can Rouleaux be excluded from testing?
perform the saline replacement technique
What antibodies does the immediate spin phase of tube testing detect?
M, N, P, ABORh, Ii
What phases other than immediate spin do anti-P and anti-I/i react at?
room temperature and 4 degrees Celsius
What antibodies does the 37 degree phase of tube testing detect?
M and N
What antibodies does the AHG phase of testing detect?
Kell, Duffy, Kidd, MN, Ss, and Lutheran (which can also react at room temperature)
How much time must pass between each donation of blood products?
whole blood, RBCs, WBCs - once every 8 weeks; platelets - no more than twice a week or 24 times a year, provided platelet count is at least 150,000/uL and at least 48 hrs. between donations; plasma - no more than twice every 7 days, with 48 hrs. between donations
What are the hemoglobin and hematocrit values acceptable for blood donation?
Hgb: >/= 12.5 g/dL, Hct: >/= 38%
What is the total volume of blood drawn in a single donation setting?
routine amount drawn is 450 mL +/- 10%; maximum bleed is 525 mL (including 2-4 tubes for testing)
What conditions would permanently defer someone from donating blood products?
use of intravenous drugs (even once); man who has had sex with another man since 1977 (even once); hemophilia; + antibody test for HIV; man or woman who has had sex for drugs or money since 1977; had viral hepatitis; cancer (except in situ basal cell carcinoma or in situ cervical cancer if successfully treated); multiple sclerosis; had coronary artery bypass surgery; had a stroke; history of babesiosis (Chagas disease); take or have taken Tegison for psoriasis; history of Creutzfeld-Jakob disease in donor or donor family members; clinical/laboratory evidence of human T-cell lymphotrophic virus (HTLV); recipient of dura mater or pituitary growth hormone; clotting or other blood disorder; sickle cell disease or other hemoglobinopathies; sexual contact with anyone who was born or lived in Africa; have been to Africa; used clotting factor concentrates; had malaria*; spent 5 or more years in Europe since 1980; received a blood transfusion in the UK or France since 1980
How much must a donor weigh?
> /= 110 lbs.
What special circumstances apply to deferrals related to malaria?
if donor has been asymptomatic after the diagnosis of malaria, the deferral time is 3 years
Give the probable genotype for the following Rh type: R(zero)
cDe
Give the probable genotype for the following Rh type: R1
CDe
Give the probable genotype for the following Rh type: R2
cDE
Give the probable genotype for the following Rh type: Rz
CDE
Give the probable genotype for the following Rh type: r
cde
Give the probable genotype for the following Rh type: r’
Cde
Give the probable genotype for the following Rh type: r”
cdE
Give the probable genotype for the following Rh type: ry
CdE
List the guidelines and blood selection for emergency transfusions and alternate blood selection.
- Always obtain a sample for crossmatching regardless of whether it can be done before units are sent out. 2. If there is time for a TNS, perform one and issue ABO compatible units; if there is no time, issue O= units, and switch to ABO compatible once the TNS has been performed. 3. All transfusion tickets MUST be stamped with “Compatibility Testing Not Completed” in red ink, and an emergency release form MUST be signed by the attending physician. 4. Perform the crossmatch ASAP, and notify the nurse or physician if: the crossmatch is complete and there are compatible units available; if an antibody has been detected; if the emergency release units were found to be incompatible with the patient. 5. In the event that emergency units are found to be incompatible, notify the medical director or the pathologist on call, and complete a blood product deviation form.
At what temperature do commonly encountered antibodies react?
37 degrees Celsius
What temperature should blood storage refrigerators be kept at?
2-8 degrees Celsius
How long are recipient samples kept in the lab?
10 days
What is the shelf life of blood after the hermetic seal has been broken?
4 hours if kept at room temperature, 24 hours if refrigerated
What temperature should whole blood be kept at during shipping?
1-10 degrees Celsius
What is the criteria for disposing of blood products?
considered regulated medical waste; should be contained in a red plastic disposable biohazard bag at least 1.5 mm thick and impervious to moisture, which are then sealed in biohazard boxes before being picked up and incinerated
What is the order of reactivity of all of the ABO blood groups with anti-H?
O > A2 > B > A2B > A1 > A1B
What is whole blood requested for?
used for patients who are actively bleeding and have lost more than 25% of their blood volume (acute blood loss), or for patients undergoing and exchange transfusion
What are the storage conditions and shelf life of whole blood?
should be stored at 1-6*C; 21 days in CPD and CP2D, 35 days in CPDA-1.
How does irradiation affect the shelf life of blood?
expires 28 days from the date of irradiation, or on the original expiration date - whichever comes first
What are packed RBCs requested for?
Increases the mass of circulating RBCs in situations where tissue oxygenation may be impaired by acute or chronic blood loss. Conditions include: oncology patients undergoing chemotherapy or radiation; trauma victims; patients undergoing cardiac, orthopedic, or other surgery; patients with end-stage renal disease; premature infants; sickle cell patients; and other causes of anemia or hemorrhage.
What are the storage conditions and shelf life of packed RBCs?
same as whole blood, with the additional condition of 45 days if they are stored in AS-1, AS-3, or AS-5
What is Rejuvenation Solution and when is it used?
Composed of pyruvate, inosine, phosphate, and adenine. It is not routinely used, but may be necessary to restore 2,3-DPG and ATP levels in RBC units collected in CPD or CPDA-1 during storage or up to 3 days after the expiration date. It can also extend the expiration date for freezing or transfusing an RBC unit, which may be necessary when rare or autologous units are involved. Washing to remove the inosine before use is REQUIRED, as it may be toxic to the recipient.
Define Frozen Deglycerolized RBCs, including their shelf life and storage conditions.
RBCs are sometimes frozen in glycerol as a means of long-term preservation for rare and autologous units. These units are free of leukocytes, platelets, and plasma. They can be stored for up to 10 years at or below -65*C. However, because the thawing process involves entering the blood unit, it is considered “open” at that point and must be transfused within 24 hours of thawing.
When would saline-washed RBCs be requested and why?
Washing removes the small amount of plasma proteins that remain in RBC units, which some patients may react to. IgA-deficient patients with clinically significant anti-IgA require washed RBCs if a transfusion is necessary. They may also be requested for infants or intrauterine transfusions.
When would irradiated RBCs (or other blood products) be requested?
Irradiation is required when the selected blood unit is from a blood relative of the recipient, or if the donor unit is HLA-matched for the recipient. It is also suggested for patients receiving intrauterine transfusion; suffering from iimmunoincompetence or immunodeficiency; have received allogeneic marrow or peripheral blood progenitor cells; are a premature newborn; or are undergoing extensive chemotherapy and/or radiation.
When would fresh frozen plasma (FFP) be requested?
used for management of bleeding patients that require factors II, V, VII, X, or XI when concentrates are not available or appropriate; abnormal coag. assays resulting from massive transfusion; patients anticoagulated with warfarin who are bleeding or require emergency surgery; replacement solution for therapeutic plasmapheresis patients treated for thrombotic thrombocytopenic purpura (TTP) or hemolytic uremic syndrome; correction or prevention of bleeding complications in patients with severe liver disease with multiple factor deficiencies; patients with deficiencies in the inhibitor antithrombin III who are undergoing surgery; cases of Disseminated Intravascular Coagulation (DIC) when fibrinogen levels are below 100 mg/dL
What are the storage conditions and shelf life of FFP?
1 year at -18C, 7 years at -65C; after thawing, FFP should be stored at 1-6*C and transfused within 24 hours of thaw time. FFP contains all of the coagulation factors, including the labile factors V and VIII which do not store well above -18*C.
What is the difference between FFP and FP24?
FFP is frozen within 8 hours of collection, while FP24 is frozen within 24 hours. The concentrations of factors in FP24 is slightly less than that of FFP, but not at levels considered to be clinically significant.
Is a crossmatch necessary for FFP/FP24?
No, but it should be ABO compatible
What is Solvent-Detergent Treated Plasma (PLAS+SD)?
Licensed by the FDA as an alternative to FFP; pooled plasma treated with a solvent detergent. It has lower potential for transmission of infectious agents, since the manufacturing process destroys lipid-enveloped viruses (HIV, HBV, and HCV). Pooled plasma is treated with the organic solvent tri(n-butyl)phosphate and the detergent Triton X-100. It is then realiquoted and frozen in uniform plastic vessels containing 200 mL PLAS+SD. Use, handling, and storage guidelines are the same as those for FFP.
When would platelets be requested?
Transfused to control or prevent bleeding associated with critically decreased circulating platelet numbers (extreme thrombocytopenia) or functionally abnormal platelets. Common recipients include patients undergoing chemotherapy or radiation; post-bone marrow transplant; postoperative bleeding.
Are platelets effective on patients with destruction of circulating platelets caused by autoimmune disorders such as ITP?
No
Is a crossmatch necessary for platelets?
No. ABO compatible units are preferred, but it is not necessary to delay transfusion if those units are not available either.
What are the storage conditions and shelf life of platelets?
5 days, stored at 20-24*C on a rotator that maintains continuous gentle agitation. Therapeutic doses for adults require multiple platelet units to be pooled, which changes the expiration date to 4 hours from the time of pooling.
What are the other names for cryoprecipitate?
cryoprecipitated antihemophilic factor; AHF; CRYO
What are the uses of cryoprecipitate?
supplement for patients with deficiencies of Factor VIII and fibrinogen as a fibrin sealant; treats patients with congenital or acquired fibrinogen defects, such as dysfibrinogenemia, a condition associated with severe liver disease in which fibrinogen is not functionally effective.
What are the storage conditions and shelf life of cryoprecipitate?
one year from collection date if stored at -18*C or lower; therapeutic doses are the result of pooled CRYO, which must be stored at room temperature and transfused within 4 hours of pooling.
What is fibrin glue?
topical hemostatic solution prepared from CRYO and thrombin; useful in controlling bleeding during a variety of procedures, such as aortic surgery; patch grafts; CSF leaks; cosmetic and nasal narrowing surgery; tooth extraction; and minor surgical procedures for patients with von Willebrand’s disease, hemophilia, and thrombasthenia.
What are plasma products derived from and how is that source collected?
Derived from recovered plasma, which is plasma expressed off of whole blood but not frozen, or the plasma expressed when CRYO is prepared. Heat treatment and/or solvent-detergent treatment kill certain viruses (HIV, HCV, HBV), and a fractionator processes the plasma into its derivatives.
What does albumin treat?
Plasma derivative used to restore plasma volume lost due to shock, trauma, surgery, or burns.
What does anti-inhibitor coagulant complex treat?
bleeding episodes in the presence of Factor VIII inhibitor
What does anti-thrombin III treat?
bleeding episodes associated with liver disease, anti-thrombin III deficiency, and thromboembolism
What does Factor IX complex treat?
prophylaxis and treatment of hemophilia B bleeding episodes and other bleeding disorders
What does fibrinolysin treat?
dissolution of intravascular clots
What does haptoglobin treat?
supportive therapy in viral hepatitis and pernicious anemia
What is IgM-enriched Immune Globulin used to treat?
treatment and prevention of septicemia and septic shock due to toxin liberation in the course of antibiotic treatment
What is the plasma protein fraction used to treat?
restoration of plasma volume due to shock, trauma, surgery, and burns
What are the Rabies, Rubella, and Varicella-Zoster immune globulins used to treat?
passive immunization due to exposure to their respective viruses
What are synthetic volume expanders and what do they do?
crystalloids and colloids for treatment of burn patients and patients in hemorrhagic shock
What kind of patient would be indicated for receiving granulocytes?
patient suffering from severe sepsis
What is the purpose of leukocyte-reduced products?
avoids febrile non-hemolytic reactions and prevents HLA alloimmunization
What is unique about the Lewis blood group system?
It is the only system not manufactured by the RBCs. Instead, the antigens are manufactured by tissue cells and secreted into body fluids (soluble Ag), where they are absorbed onto the RBC membrane (they are not an intrinsic part of the membrane)
Define an allergic transfusion reaction.
Caused by interaction of allergen in transfused blood with preformed antibodies in the recipient; sometimes the antibody may be in the donor blood. Symptoms include inflammation of the skin and/or mucus membranes, though serious reactions may cause breathing difficulty.
Define an acute hemolytic transfusion reaction (AHTR).
Caused by rapid destruction of donated RBCs during, shortly after, or within 24 hours of a transfusion due to ABO incompatibility. Symptoms include pain, fever, and sometimes severe side effects such as kidney failure.
Define a delayed hemolytic transfusion reaction (DHTR).
Caused by the recipient developing antibody to the donated RBC antigens 24hrs-28days after transfusion. Symptoms are milder than in AHTR, and may even be absent.
Define a delayed serologic transfusion reaction(DSTR).
Cause is the same as a DHTR, but there are no clinical symptoms, nor laboratory evidence of hemolysis.
Define a febrile non-hemolytic transfusion reaction (FNHTR).
Most common reaction; characterized by fever and/or chills during or up to 4 hrs. following transfusion.
Define a hypotensive transfusion reaction.
Characterized by a drop in systolic blood pressure soon after a transfusion begins, that responds quickly to cessation of transfusion, and supportive treatment.
Define post transfusion purpura (PTP).
Recipient develops an antibody against platelets, resulting in the rapid destruction of both donor and recipient platelets.
Define transfusion-associated circulatory overload (TACO).
Caused by the recipient not being able to effectively process the volume of blood/blood products being transfused, due to either too large/fast of an infusion, or by an underlying heart or kidney condition. Symptoms include difficulty breathing, cough, and fluid in the lungs.
Define transfusion-related acute lung injury (TRALI).
The mechanism of this reaction is not well understood; thought to be caused by and antibody in the donor blood. Symptoms include fluid in the lungs not related to TACO; it is the leading cause of transfusion-related death.
Define transfusion-associated dyspnea (TAD).
Respiratory distress within 24 hours of transfusion that cannot be defined as TACO, TRALI, or an allergic reaction.
Define transfusion-associated graft vs. host disease (TAGVHD).
Caused by donor T-lymphocytes (“graft”) rapidly increasing in the recipient (“host”) and then attacking the recipient’s cells. Symptoms include fever, a characteristic rash, enlargement of the liver, and diarrhea, all occurring 2 days to 6 weeks after transfusion.
Define transfusion-transmitted infection (TTI).
Bacterium, parasite, virus, or other potential pathogen transmitted through donor blood products.
What antibodies are found in the plasma of Bombay individuals?
anti-A, anti-B, anti-A,B, and anti-H.
What enzymes are used in blood bank testing and what blood group antigens do they affect?
Enzymes: ficin, papain, bromelain, and trypsin. They are the best method for detecting Rh antibodies; they are capable of detecting Lewis, autoanti-I, and anti-P1 antibodies; and they detect Kidd antibodies, especially if the AHG phase of testing is performed.
What criteria makes a patient eligible for Rh immune globulin (RhIG, RhoGam)?
Rh= women as an antenatal dose at approximately 28 weeks or at any time during pregnancy; Rh= women who have delivered a baby that is Rh+, Rh unknown, or Rh invalid; Rh= women who have a suspected exposure to fetal RBCs during pregnancy such as in cases of fetomaternal hemorrhage, trauma, miscarriage, amniocentesis, and cordocentesis; any Rh= patient that has been transfused with components that may contain Rh+ RBCs.
Define elution.
dissociation of antibodies that are attached to the surface of RBCs; used to identify complicated antibodies, such as in the workup of transfusion reactions or HDFN, and in the workup of warm autoantibodies.
Define forward grouping.
testing patient red cells against anti-A1, anti-B, and anti-D antisera for the presence of the corresponding antigens to determine a patient’s blood type and Rh status
Define DAT.
Direct Antiglobulin Test, Direct Coomb’s Test; determines whether RBCs are coated with complement and/or antibody in vivo (inside the body).
Define polyspecific AHG.
special antisera (anti-human globulin) used in the DAT that contains anti-IgG, anti-C3b, and anti-C3d
Define anti-A1 lectin.
derived from the seed of the Dolichos biflorus plant, used to distinguish between A1 RBCs and A2 (will agglutinate A1 cells)
Define Wharton’s jelly.
gelatinous substance that provides insulation and protection within the umbilical cord; RBCs from cord blood must be washed to remove this jelly as it can interfere with blood bank testing
Why aren’t reverse blood typings done on newborns.
newborns don’t have fully developed antibodies in their plasma, so reverse typing will always be negative regardless of their true blood type
Explain weak antigen expression and how you would solve its ABO discrepancy.
Caused by weaker subgroups of type A or B; disease states; transfusion with Type O RBCs (babies and massive transfusion); and transplantation. Solutions include increasing incubation time, decreasing incubation temperature (use an autocontrol if cold incubation is used), examining tubes microscopically, and sending samples to the ARC for elution and adsorption studies if needed.
Explain altered protein concentration and how you would solve its ABO discrepancy.
Caused by the presence of Wharton’s jelly, or by disease states with high serum or plasma protein. Check the patient’s medical history to confirm this, and thoroughly wash the RBCs before performing testing.
Explain cold reactive antibodies and how you would solve their ABO discrepancies.
Cold reactive antibodies may coat the RBCs and cause agglutination, resulting in false positives. Wash the RBCs several times in warm saline, allow them to cool back down to room temperature, and then perform the type and screen.
Explain neutralization of anti-A1 and/or anti-B and how to solve its ABO discrepancies.
Soluble blood group substances in plasma or serum may neutralize the antisera and cause false negatives. This can be solved simply by washing the RBCs before testing.
Explain polyagglutination and how to solve its ABO discrepancy.
Caused by the activation of cryptic antigens on the RBCs, which may cause spontaneous agglutination (false positives). Rule out all other causes before assuming this one Test the patient cells with type AB donor serum or plasma; if cells agglutinate they are likely polyagglutinable. The sample may be sent to the ARC reference lab for special lectin testing.
Explain acquired B phenotype and how to solve its ABO discrepancy.
Caused by certain bacteria which cause the deacetylation of the A antigens so that they resemble B antigens; this should be considered if the patient’s cells are strongly reactive with anti-A1, weakly reactive with anti-B, and reverse ABO typing corresponds to type A. Check the patient’s history for GI tract carcinoma; perform an autocontrol (the anti-B in the patient’s plasma will not react with the acquired B); and send the sample to the ARC for more extensive testing.
Explain why reverse ABO discrepancies may be seen in the elderly, in newborns, and in immunodeficient patients.
Immunodeficient patients may not produce detectable levels of anti-A and anti-B; these antibodies may also be weak in the plasma of normal elderly patients, and are completely absent in the plasma of newborns. Check the patient’s age and diagnosis to confirm this cause.
Explain type A subgroups and how to solve their ABO discrepancies.
Anti-A1 in the plasma of A2, A2B, and other A subgroups will agglutinate A1 reagent cells in reverse typing. Test the sample with anti-A1 lectin and A2 reagent cells to confirm.
Explain cold autoagglutinins and how to solve their ABO discrepancies.
Strongly reactive cold autoagglutinins (such as anti-I, anti-IH, anti-IA, and anti-IB) can agglutinate RBCs of adults, including autologous cells and reagent cells, at room temperature. With few exceptions, agglutination caused by cold autos is weaker than that of anti-A or anti-B. Prewarming technique should be used on samples such as this, though it should be noted that weakly reactive examples of IgM anti-A and anti-B may not be detected, as 37*C is above the optimal reactivity temperature. In that case, there is also the option to perform a cold adsorption to remove the cold auto from the plasma.
Explain unexpected alloantibodies and how to solve their ABO discrepancies.
Unexpected alloantibodies that react at room temperature (such as anti-P1 and anti-M) may agglutinate the red cells used for reverse typing if the cells carry that antigen. One or more of the Surgiscreens will also be agglutinated when using the gel method (or at room temperature in the tube method). **Rare plasma may react with an antigen on the reverse cells that is not on the antibody screening cells. Additional testing with cells lacking the suspected antigen can confirm the presence of the antibody.
Explain atypical plasma and how to solve its ABO discrepancies.
Plasma with abnormal concentrations of plasma proteins, or with altered plasma expanders of high molecular weight, can agglutinate reagent cells (false positive); similar to Rouleaux. The plasma can be diluted 1:3 with saline, or a full saline replacement can be performed.
What is the criteria for selecting blood for neonatal exchange transfusions?
The blood needs to be compatible with both the baby and the mother; CMV=; Hgb S=
Why are cells washed in the AHG phase of testing?
Removes any unbound IgG or plasma proteins that can interfere with testing.
