Blood Bank Exam 3 Flashcards
1
Q
pRBC unit volume
A
250 mL
1
Q
Whole Blood unit volume
A
450 mL
2
Q
HLA Antigens
A
Antigens associated with leukocytes, especially important in transplant patients
3
Q
Irradiating blood components
A
- eliminates T cells
- prevents graft vs. host
- Directed units from blood relatives
4
Q
Frozen RBC
A
- <180 mL
- must wash to remove glycerol
- Expires 24 hours after thaw and wash
5
Q
Washed RBCs
A
- prevent allergic reaction
- expires 24 hours after wash
6
Q
FFP
A
- 1 year expiration
- 220 mL
- Must be ABO compatible
- does not care about Rh compatibility
7
Q
Cryo
A
- “Cryoprecipitate”
- Concentration of Factors: VIII, I, Vwf, XIII
- 15 mL
- Frozen at 18C or lower
- Expires 6 days after thaw (store at RT)
- Must be ABO compatible
8
Q
Factor Concentrates
A
- handled by pharmacy
- one factor at a time
- ABO not an issue
9
Q
Platelet Concentrates
A
- 300 mL
- ABO compatible if possible
- Avoid Rh pos units given to Rh neg patients
10
Q
Compatibility Testing sample
A
- labeling + armband
- no hemolysis
- XM sample expires after 72 hours
- sample kept for 7 days after transfusion
11
Q
Neonate transfusion requirements
A
- Low volume (50-80 mL)
- Fresh (<7 days old, low K+, high 2,3 DPG)
- prewarmed units
- CMV negative
- Irradiated
12
Q
Donor testing
A
- infectious diseases
- ABO/Rh
- weak D
- antibody screen (if antibody, not for transfusion)
- DAT?
13
Q
Major Crossmatch
A
Patient serum + donor cells
14
Q
Minor Crossmatch
A
Patient cells + donor serum
15
Q
Abbreviated Crossmatch
A
- IS testing only
- no history or evidence of antibody EVER
16
Q
Extended Crossmatch
A
- IS and AHG testing
- history or evidence of antibody
17
Q
Computer Crossmatch
A
- no testing, computer runs an algorithm
18
Q
If there is an unexpected incompatibility
A
you must investigate!!!
19
Q
Possible causes of incompatibility
A
- ABO
- Autoantibody
- Alloantibody
- Positive DAT on donor cells (slipped through collection screening)
- Rouleaux
20
Q
Whole Blood compatibility
A
Must meet both RBC and plasma compatibility requirements
21
Q
How long can blood be returned after it is checked out if not used?
A
30 minutes
22
Q
How many units triggers a massive transfusion protocol?
A
5 units
23
Q
Describe a massive transfusion protocol
A
- 1 unit FFP per unit pRBCs (catch up if needed)
- 1 unit platelets and 1 unit cryo every 10 units
24
Name for massive transfusion in neonates
Exchange Transfusion
25
Emergency Transfusion allows
uncrossmatched O negative pRBCs to be given
26
Who can receive uncrossmatched O positive pRBCs in an emergency?
Males and women over 65
27
TACO
- "Transfusion Associated Circulatory Overload"
- most common in elderly and infants
28
TRALI
- "Transfusion Related Acute Lung Injury"
- Anti-WBC antibodies
29
PTP
- "Post Transfusion Purpura"
- platelet allo-antibody
- depletion of platelets and coag factors
30
Immediate Intravascular Hemolysis
- IgM (via complement), IgG, or ABO mixup
- anti-A, K, Jka, Fya are most common
we don't talk about Bruno nonono
31
Delayed Extravascular Hemolysis
- anamnestic response
- Rh antibodies, anti-Jka, K, Fya
- 3-7 days post txn
32
Damage to Transfused Cells
- Heat Damage (blood warmers, storage)
- Physical Damage (pumps, heart valves, ECMO)
33
What would indicate a "dead" unit on visual inspection?
Brown, purple, clotted, or severely hemolyzed
34
Proceed to Extended Evaluation if:
- Discrepancy in Clerical Check
- Post DAT pos and pre DAT neg or weaker
- Visual hemolysis in post sample
- Post serum HGB is 20mg/dL higher than Pre
35
If there are RBCs in the urine with a transfusion reaction
it likely is unrelated to the reaction
36
Transfusion Reaction Reporting
- physician
- blood bank director
- accrediting agencies
- (if fatal) FDA
- (if fatal) Center for Biologic Evaluation & Research
37
If a post-transfusion reaction sample is hemolyzed
call for second collection to eliminate possibility of phlebotomist error
38
Febrile Transfusion Reaction
- >1 degree C rise in temp (fever)
- anti-WBC antibody (complement activated)
39
Erythroblastosis fetalis
neonate with HGB <15 g/dL
40
Kernicterus
brain damage from extremely high bilirubin, usually in neonates
41
What types of HDN require antibody titers?
Rh and 'other'
42
Critical antibody titer level
1:32
43
How can you tell allo-anti-D from Rhogam on an IAT?
You can't. You need patient history.
44
Rhogam dosage during term
- 50 ug at <12 weeks
- 300 ug at >= 12 weeks
45
What indicates need for transfusion on the Liley graph?
zone 3
46
What in amniotic fluid can indicate severity of HDN?
bile pigment, measured with optical density at 450 nm
47
PUB sample testing
- "Percutaneous Umbilical Blood"
- needle guided with ultrasound, drawn from umbilical vein
48
Fetal Lung Maturity
Ratio of Lecithin to Sphingomyelin (L/S Ratio)
- >2.0:1 = mature
- 1.5:1 = 40% chance of respiratory distress
- <1.5:1 = 70% chance of respiratory distress
49
FMH Screen
- "Fetal Maternal Hemorrhage"
- Positive = >15mL fetal bleed, reflex to KB stain
50
KB Stain
- "Kleihauer Betke"
- count 4k cells, determine % fetal cells
51
1 vial of Rhogam covers
15 mL pRBC or 30 mL WB
52
Rhogam dosage calculation
(% fetal cells x 50) / 30
Round Up
