Compatibility Test (LEC) Flashcards
This is a necessary procedure to be done before operation or transfusion
Compatibility Testing
Who started compatibility testing?
Well and ottenberg
What are the purpose of compatibility testing?
- provide appropriate safe transfusion of blood
- select blood components that will not cause harm to the recipient and have acceptable survival when transfused
Compatibility testing will confirm _______________ between the component and ___________ and will detect the _______________
- ABO incompatibility
- recipient
- most clinically significant unexpected antibodies
What are the pre-transfusion testing procedure comprised of?
Donor unit:
- ABO
- Rh
- TTD (transfusion transmissible disease)
Recipient unit:
- ABO
- Rh (not including Weak D)
- IAT: Ab screen
- Crossmatching (major/minor)
What are the three categories of compatibility testing?
Pre-analytical (Px ID, specimen collection, review Px history)
serological testing (ABO/Rh, Ab detection/ID, crossmatch)
post-analytical procedures (labelling units and forms, released for recipient, inspected for abnormalities)
Specimen collection should be collected in tube with ______________________
EDTA and NO additives
Venipuncture causes hemolysis, sample is _________________
rejected
True hemolysis indicates _______________________
complement activation
What is the color of the tube w/o additives where _________ sample is collected than _____________
RED, serum than plasma
If the sample is drawn from the IV line, the infusion should be _______________________________
stopped for 5-10mins prior to collection
If both of the Px’s arm has IV line, collect in _______________
ankle vein
If amputated leg and has IV on both arms, sample is collected in _______________
IV line but discard first 10mL because it is diluted
Testing should be performed on samples for __________________
less than 72hrs or 3days
What are the materials used for labelling donor red cell?
Radioisotope or radioactive materials
What is the newer method of crossmatching?
Computer crossmatch
Which method of crossmatching is better to be performed?
Conventional test tubes
What are the new technologies of crossmatching?
Column agglutination technology
Solid-phase technology
Electromagnetic (EM) technology
In the IS phase of serological crossmatch it detects ___________________, and in AHG phase detects ________________
ABO Incompatibilities (IgM)
Rh, Duffy, Kidd, other IgG
In crossmatching, for how long will recipients serum and donor red cell be preserved?
1 week or 7 days
In crossmatching, fresh sample of Px is needed after _________
48hrs of transfusion
In cross matching, RBCs must be infused within ____________
4hrs
What are the two types of crossmatched?
Major and Minor crossmatch
In Major crossmatch, uses _____________________
DCRS
Donor red cell, Px serum
In Minor crossmatch, uses _____________________
DSRC
Donor serum, Px red cell
Between the two crossmatch type, which is routinely performed?
Major crossmatch
Why is minor crossmatch unnecessary and almost obsolete?
Most blood transfused are packed cell w/ little Ab
Who developed the standards for blood banking?
AABB (American association of Blood Banks) and FDA (Food and Drug Administration)
According to the AABB Standard:
The crossmatch shall use methods that demonstrate _________________ and _______________________ and shall include an _____________________
ABO incompatibility
clinically significant Ab to red cell Ags
antiglobulin phase
Who regulates blood bank in hospitals in the Philippines?
DOH, NGO (Philippine red cross)
What is the reference lab of TTD or transfusion transmissible disease?
RITM (Research institute for tropical medicine)
To maintain 40:1 Ag-Ab reax, you need to add __________________
2 drops of Px serum, 1 drop of donor red cell
To remove unbound Abs, you need to ________________
wash 3x
TRUE OR FALSE:
Crossmatching is routinely performed in secondary and tertiary hospital
FALSE
Only in TERTIARY hospital
Segments where donor cells are taken from, are ______________
sampling of the minor and eliminate having to open the actual unit
What is the sequence of tests in compatibility testing?
ABO/Rh
Ab screening
If no unexpected Abs = perform crossmatching
After Ab screening in compatibility testing, if Abs are NOT detected, what is the next step to be performed?
perform IS phase using Px serum and donor blood suspension
= INCOMPLETE CROSSMATCH
After Ab screening in compatibility testing, if Abs are detected, what is the next step to be performed?
IS, LISS, and AHG phase is performed
= COMPLETE CROSSMATCH
In what phase of Ab screening will verify the donor ABO incompatibility, and detect most Abs against donor cells?
IS phase, AHG phase
Crossmatching will not: _____________________
Guarantee normal survival of RBCs Hgb and Hct after transfusion prevent Px from developing Ab detect all Ab and error in ABO/Rh detection Prevent delayed tranfsuion reaxn
Causes of + result in serological crossmatch?
- incorrect ABO grouping
- alloAb in Px serum
- autoAb in Px serum
- prior coating of donor’s RBC w/ protein
- abnormalities in Px serum
- presence of Dextran (expanders)
- high albumin:globulin ratio
- Ab against caprylate
- contaminants in test system
The conatmination of bacteria shows ________________
hemolyzed plasma
WHat is the storage temperature of blood units?
1-10 deg C
If the units is not stored in correct temperature, it must be returned within _________________
30mins of issue
When the units are pre-warmed at 37deg C, it must be transfused w/n _________
1hr
After 1hr of issuing blood unit, it must be transfused w/n ____________
24hrs
TRUE OR FALSE:
It is important to indicate in the tag of blood unit if its not crossmatched
TRUE
TRUE OR FALSE:
Even blood has already be transfused, compatibility testing should still be performed
TRUE
What unit of blood is given in emergency cases?
Group O, Rh-negative red cells or AB plasma (women below childbearing age)
Group O, Rh-positive (male or elderly)
If the clinical urgency is immediate, give ___________
Group O Rh NEG pRBC
If the clinical urgency is minutes, give ___________
ABO and Rh D type = group specific blood
If the clinical urgency is hour, give ___________
ABO and Rh D type = complete crossmatch
If the recipients ABO blood group is AB, what is the 1st to 4th choice of blood?
1st - AB
2ND - A
3RD - B
4TH - O
Rh D positive pRBC can be transfused to ______________ in emergency
Rh negative patients (post menopausal females, older men)
TRUE OR FALSE:
It is NOT safe to transfuse Rh NEG blood to Rh POS px
FALSE
Rh D negative blood can safely be transfused to Rh D positive patients.
Massive transfusion is defined as______________
transfusion approaching or exceeding the recipient’s own blood volume w/n 24hrs
TRUE OR FALSE:
INCOMPLETE crossmatch is not necessary for massive transfusion
FALSE
COMPLETE crossmatch is unnecessary
What type of blood units should be given for massive transfusion?
ABO identical units
What is the purpose of type and screen?
to conserve blood inventory
When will crossmatching be performed if type and screen is done?
If blood is needed, it is retrieved for crossmatching (only IS phase)
Neonate of _______ old does not have _________ but has __________
<4months
Abs
Ag
If clinically significant Abs are detected in neonates, this is _____________ and must be transfused w/ ____________
maternal Abs
Ag NEG units
Whose sample is used for corssmatching among neonates?
Infant or maternal serum
These are small aliquots of larger units for infant transfusion
Pedipacks or Satellite Bags
If whole blood bag is given to neonates, they may suffer from ___________
hypervolemia
This refers to a donation from recipient for later use
Autologus
Autologous is commonly performed by ______________
Px w/ rare blood type (Bombay) and religious restrictions (Jehovah)
According to the AABB, what must be fulfilled in new technologies of crossmatching?
- critical elements have been validates
- no clinically significant Abs (present and past)
- Px ABO and Rh is done twice
- system alert medtech for ABO and Rh discrepancy
Records should be maintained for at least _____________
5yrs