practicum 50 multiple choice Flashcards
Abs that can cause a HDN
ABO/Rh, Kell, Duffy
Abs that may cause HTR
Kidd, ABO incompat.
Abs that may cause Delayed HTR
Kidd (jka, jkb), Duffy, Kell, MNS
How are cold agglutinans excluded from testing?
cold agglut-absorption
How is rouleaux excluded from testing?
saline replacement
What Abs are detected at IS?
Lewis, MN, P1
What Abs are detected at 37 degrees?
Rh, MN
What Abs are detected at AHG phase?
Kell, Duffy and Kidd
Interval between donations
8 weeks
minimum Hgb for donation
> 12.5
minimum Hct for donation
> 38%
maximum volume of blood drawn during donation
525 mL (normal 450 mL)
minimum body weight for donation
110 lbs
max body temp for donation
37.5/ 99.5
how long is the deferred period if person spent time in a malaria area?
1 year
how long is the deferral after having malaria?
3 years
what blood type is used for emergency release and alternate blood selection?
O pos
Refrigerator temp for RBCs
1-4 degrees
shelf life after breakage of hermetic seal
24 hrs
length of time recipient samples are saved for
7 days
temp range during whole blood shipping
1-10 C
reason to discard a unit of blood
hemolyzed
clots
which blood group has the most reactivity with anti-H
Group O is strongest
hemophiliac patient would need what type of blood component?
cryo (contains concentrated fibrinogen and factor VIII)
what is unique about the Lewis system
only blood group system not manufactured by the RBCs.
pregnant women may present Le(a-b-) and produce Lewis Abs even though true phenotype is Le(a-b+). can show in saliva and tears
what Abs are found in Bombay individuals?
ALL
Anti-A, Anti-B, Anti-A,B, H
what blood group Ags are enhanced by enzymes?
Lewis, Rh, Kidd
what blood group Ags are destroyed by enzymes?
Duffy, MNS
what would you expect if a Rh neg patient who has never been transfused or pregnant was transfused with pos donor blood?
no transfusion reaction because no Abs are present due to no previous exposure
when should Rhogam be given
Rh - mother Rh+ baby
define elution
used to remove Abs that may be bound to the RBCs
define forward typing
using forward known serum Abs to detect unknown Ags
define DAT
used to diagnose HDN, HTR and AIHA
if + perform an elution to remove Ab to ID specific eluate
(( Direct Coombs use patient cells))
define polyspecific
has both complement and IgG
what is the anti-A1 lectin used to detect
used with A1-ABO discrepancy
where do you find whartons jelly
on cord blood cells
why aren’t reverse blood groupings done on newborns
no developed Abs
define febrile nonhemolytic reaction
chills, fever, increase in temp by 2 degrees
what could a weak supgroup of A cause
ABO discrepancy
what would you use distinguish between an A1/A2 discrepancy?
dolichus Biflorus
if the mother is O and the baby is A and there is HDN what would you transfuse with?
Group O blood
what would be the next step if cord blood and mother sample have a strong + DAT?
elution
would A2B and anti-A1 cause a discrepancy?
yes
why are cells washed in the AHG test?
to prevent neutralization by globulins
what is the reason for a mixed field result on a DAT for a patient who has been previously transfused
2 cell population in the patients blood
what type of sample do you need for compatibility testing?
fresh serum/plasma
why do you need a fresh serum sample for compatibilty
to preserve complement
what type of elution is required for HDN
Acid Elution
what is a cause for deferral during blood donation
if they tested positive for HBsAg
