Blood Bank Flashcards
(388 cards)
In 2012, the AABB’s Clinical Transfusion Medicine Committee issued 3 clinical practice guidelines regarding RBC transfusion. That are they?
- Adhere to a restrictive transfusion strategy (7 to 8 g/dL as a transfusion trigger) for hospitalized, stable patients. 2. Adhere to a restrictive transfusion strategy in hospitalized patients with preexisting cardiovascular disease and consider transfusion for patients with symptoms or with a hemoglobin level of 8 g/dL or less. 3. Transfusion decisions should be influenced by symptoms as well as hemoglobin concentration. There was high-quality evidence for recommendation #1 and moderate-quality evidence for recommendation #2.
What is contained in prothrombin complex concentrate and in activated prothrombin complex concentrate?
PCC contains vitamin K-dependent clotting factors (factors II, VII, IX, and X) (mostly unactivated forms) and proteins C and S. aPCC has higher amounts of the activated forms (factors VIIa and Xa). To prevent activation, most PCC contain heparin.
Are prothrombin complex concentrates approved for hemophilia B?
Neither PCC nor aPCC are approved for hemophilia B (factor IX deficiency) because recombinant or purified factor IX products are available. PCC is approved for congenital prothrombin or factor X deficiencies, and is used off-label for urgent reversal of warfarin over-anticoagulation. aPCC is approved for acute bleeds in hemophilia A or B and in patients with clotting factor inhibitors.
Prothrombin complex concentrates are produced by…
PCC are produced by ion-exchange chromatography from the cryoprecipitate supernatant of large plasma pools after removal of antithrombin and factor XI. Different processing techniques involving ion exchangers enable the production of either three-factor (i.e., factors II, IX and X) or four-factor (i.e., factors II, VII, IX and X) concentrates with a final overall clotting factor concentration approximately 25 times higher than in normal plasma. To prevent activation of these factors, most PCC contain heparin. PCC may also contain the natural coagulation inhibitors protein C and protein S. The PCC are standardised according to their factor IX content. All PCC undergo at least one step of viral reduction or elimination (solvent detergent treatment, nanofiltration, etc.).
Dabigatran (Pradaxa) is an alternative to warfarin FDA approved 10/2010 for patients with atrial fibrillation. Currently there is no reversal medication available. If there is bleeding, the recommendation is ___. If there is severe bleeding or CNS bleeding, the recommendation is ___.
If there is bleeding, the recommendation is to give plasma. If there is severe bleeding or CNS bleeding, the recommendation is to give plasma and Novo-7.
At UTMCK, all factor concentrates are stored in and dispensed from the pharmacy. The only non-blood product in our blood bank is ___.
At UTMCK, all factor concentrates are stored in and dispensed from the pharmacy. The only non-blood product in our blood bank is Rh IG.
3-factor PCCs and 4-factor PCCs.
All prothrombin complex concentrates contain factors II, VII, IX, but some products contain no or very little FVII. PCCs with normal amounts of VII are known as 4-factor PCCs while the products without VII are 3-factor PCCs. In the United States, two 3-factor PCCs are available (Bebulin VH, Profilnine, Profilnine SD), and one 4-factor PCC is available (Proplex T).
FFP vs. PCC for emergency anticoagulation reversal for warfarin.
FFP contains normal levels of all the coagulation factors while PCCs contain factors II, IX and X with variable amounts of factor VII in a concentrated form. PCCs are virally inactivated and can be given in a small volume without the need to thaw the product first. FFP however, has to be thawed before use, must be blood group specific and because it needs to be given at a dose of at least 10–15 mL/kg, it risks precipitating volume overload in the recipients who are often frail and elderly. Some guidelines recommend PCCs over FFP because of their more rapid administration and complete INR correction.
In UTMCK massive transfusion protocol, how many units of RBCs are in each cooler?
4 units RBCs per cooler. After 3 coolers, there is no need to crossmatch additional units, since 8-10 units RBCs is considered complete blood volume replacement.
All platelet units at UTMCK are (whole blood derived/apheresis derived).
All platelet units at UTMCK are apheresis derived.
For platelet apheresis donation, single dose aspirin or piroxicam use is a __ day deferral, daily aspirin or piroxicam use is a __ day deferral, and clopidogrel and ticlopidine use is a __ day deferral.
For platelet apheresis donation, single dose aspirin or piroxicam use is a 2 day deferral, daily aspirin or piroxicam use is a 14 day deferral, and clopidogrel and ticlopidine use is a 14 day deferral.
Patients undergoing cardiopulmonary bypass may have platelet dysfunction due to ___.
Patients undergoing cardiopulmonary bypass may have platelet dysfunction due to activation of platelets during the procedure. Because of this pump effect, post-bypass platelet transfusion is based upon clinical findings rather than platelet counts.
What two conditions are absolute contraindications for platelet transfusion, and what condition is a strong relative contraindication?
Absolute contraindications: TTP and HIT. Immune thrombocytopenia (idiopathic thrombocytopenic purpura and post-transfusion purpura) are strong relative contraindications; Do not transfuse unless severe thrombocytopenia with life-threatening bleeding; Large numbers of units may be needed due to rapid immune destruction.
Can platelets be transfused with an IV pump?
The use of an IV pump is contraindicated for transfusion in most circumstances because the platelets could become activated, depending upon the pump type and FDA clearances. At UTMCK, since only some of our pumps are FDA approved for platelet transfusion and it could cause confusion, nursing policy is that IV pumps are not to be used for platelet transfusion.
What is the #1 cause of transfusion-related deaths?
TRALI.
Are FFP, FP24, and 5-day cold plasma considered equivalent blood products?
Generally yes, except that FP24 and 5-day cold plasma should not be used for replacement of Factor V or Factor VIII. However, selective Factor V deficiency is rare, occuring in ~1/million and the general population and is not associated with a bleeding tendency; also, Factor VIII concentrate is an available product, and cryoprecipitate can be used if factor concentrate is unavailable. So FFP, FP24, and 5-day cold plasma are basically equivalent blood products.
At UTMCK, we use FP24 or 5-day cold plasma instead of FFP for all uses except for ___.
At UTMCK, we use FP24 or 5-day cold plasma instead of FFP for all uses except for the NICU, for preparation of red cells for exchange transfusion, and for therapeutic apheresis.
Place the following blood types in decreasing order of amount of H antigen: A1, A2, A1B, A2B, B, O.
O»A2>B>A2B>A1>A1B.
What lectin is used to distinguish A1 from A2 RBCs?
Dolichos biflorus lectin is used to distinguish A1 from A2, as it will agglutinate A1 but not A2 RBCs.
In ABO blood types, there are at least __ different A subgroup alleles and ___ B subgroup alleles, as well as __ different O alleles.
In ABO blood types, there are at least 41 different A subgroup alleles and 18 B subgroup alleles, as well as 61 different O alleles. This heterogeneity makes ABO typing with DNA technologies complicated. In addition, the same genotype gives rise to different phenotypes even within families, which further adds to the complexity.
The Rh system has at least (#) antigens, most notably (5).
The Rh system has at least 45 antigens, most notably C, c, E, and e antigens, which are carried on the RhCE protein encoded by the RHCE gene, and the D antigen on the RhD protein encoded by the RHD gene. The RHCE and RHD genes are 96% homologous and are adjacent to one another on chromosome 1.
What are the Rh null and Rh mod phenotypes?
The Rh antigens are carried on hydrophobic 12-pass transmembrane proteins. The RhAG protein does not carry Rh antigens, but is important for bringing the RhD and RhCE proteins to the membrane. Lack of RhAG results in the absence of Rh antigen expression (Rh null phenotype) or marked reduction of Rh antigen expression (Rh mod phenotype).
What are the regular and amorph types of Rh-null?
Rh-null RBCs lack expression of Rh antigens, are stomatocytic and spherocytic, and affected individuals have variable degrees of anemia. The regulator type is caused by mutations in the RHAG gene so they have no Rh or RhAG proteins, and the amorph type is caused by mutations in the RHCE gene on a deleted RHD background so they have no Rh proteins and reduced RhAG proteins.
Anti-D, anti-c, anti-C, anti-e, and anti-E Rh antibodies. Which cause severe HDFN and which cause no or mild HDFN?
Anti-D and anti-c can cause severe HDFN, while anti-C, anti-e, and anti-E usually cause no or mild HDFN.