Test Bank Solution Manual for Blood Bank Reviewing concepts Already Passed
All of the following may be used to perform an antibody screen for an infant less than 4 months old
except: - Answers paternal serum
In which of the following situations can the crossmatch test be omitted? - Answers in a patient who has
recieved a massive transfusion within a 24-hour period (Feedback: The performance of a crossmatch for
a massively transfused patient may be omitted if the total patient volume has been exchanged (10 to 12
units of whole blood) within 24 hours)
What are the two components of the major crossmatch? - Answers Donor red cells and recipient serum
To what does the abbreviation "MSBOS" refer? - Answers Maximum blood order schedule
How long following transfusion must the recipient sample be stored? - Answers 7 days (Feedback: The
recipient's sample should be stored at 1 to 6 C for 7 days in case there is a transfusion reaction that
requires investigation)
Compatibility procedures will address all of the following except to: - Answers prevent antibody
formation (Feedback: The compatibility test may prevent the formation of anti-D, but all other antigens
are not matched)
To increase the sensitivity of the antibody screen in a compatibility test, what can be done? - Answers
Increase the serum to cell ratio.
Use an enhancement such as polyethylene glycol.
Extend the incubation time
Antibody screening of the recipient is performed as a component of compatibility testing to detect: -
Answers red cell alloantibodies (Feedback: The antibody screen detects alloantibodies that the recipient
made to red cell exposure from pregnancy or prior transfusions)
The following red cell antigen frequencies:
K
10%
E
30%
K
90%
P1
,80%
Which of the following red cell alloantibodies would be responsible for incompatible crossmatches with
one 1 of 10 random donor units? - Answers anti-K (Feedback: Anti-K is incompatible with 1 in 10 units of
red blood cells)
An infant less than 4 months old requires which procedures for compatibility testing? - Answers ABO
and D typing and antibody screen initially only; units released without additional testing if the screen is
negative (Feedback: An infant less than 4 months old does not make red cell antibodies and therefore
does not need to be checked with each transfusion. Initial screens detect antibodies made by the
mother)
In which phase of reactivity would rouleaux typically be detected in the screen? - Answers 37 C
(Feedback: In the screen, 37 C is typically where rouleaux is initially detected)
An antibody screen on a patient with a prior history of transfusion was negative. The crossmatch,
performed at immediate spin and antihuman globulin, was incompatible with 1 unit selected. The next
step in the investigation would be to: - Answers perform a direct antiglobulin test on the incompatible
unit (Feedback: The most likely reason for the incompatibility is that the blood unit has a positive direct
antiglobulin test or the patient has developed an antibody to a low-frequency antibody. If the direct
antiglobulin test is negative, testing the patient's serum against a selected cell panel of low-frequency
antigen positive cells should be performed)
Patient M.M. was admitted to the hospital with acute bleeding. Anti-E was detected in the patient's
serum. Four E-negative units of blood were crossmatched for the patient. The units were compatible at
immediate spin and following the antiglobulin test. After the antiglobulin test was performed, IgG
sensitized red cells gave a 2+ agglutination reaction. The proper interpretation of this 2+ agglutination
reaction is the: - Answers antihuman globulin washing procedures was adequate (Feedback: IgG-
sensitized red cells should be positive if adequate washing was performed and antihuman globulin
reagent was added)
A group O patient was crossmatched with group B red blood cells. What phase of the crossmatch will
first detect this incompatibility? - Answers Immediate spin (Feedback: ABO incompatibilities should be
detected on immediate spin)
When group O blood is not available for transfusion, what is the next alternative? - Answers None
(Feedback: Group O individual has both anti-A and anti-B present in serum, which is incompatible with
all blood groups other than group O)
The use of the electronic (computer) crossmatch is restricted to recipients who: - Answers do not have
clinically significant antibody (Feedback: The electronic (computer) crossmatch may be performed only
on patients who do not have or have a history of a clinically significant antibody)
The immediate spin or abbreviated crossmatch is an acceptable procedure if the recipient: - Answers
has no prior or existing clinically significant antibodies
, If an emergency exists and there is not enough time to perform a crossmatch for red cells, what is the
correct procedure? - Answers release group O, D-negative whole blood (Feedback: Group O D-negative
red blood cell units should be released and the crossmatch procedure completed as soon as possible)
For autologous units transfused within the collection facility, which part of the compatibility procedure
is not required? - Answers Antibody screen (Feedback: Autologous units are given to the donor and do
not require an antibody screen unless nonautologous units are also to be transfused)
Which of the following blood products requires a crossmatch to be performed before issuing? - Answers
Granulocyte concentrates that have more than 2 mL of red blood cells
(Feedback: Granulocytes may contain a significant amount of red blood cells because they are obtained
from the "buffy coat" layer during apheresis. These units would require crossmatching before release)
Feedback: Granulocytes may contain a significant amount of red blood cells because they are obtained
from the "buffy coat" layer during apheresis. These units would require crossmatching before release.
Select the correct statement regarding the collection of a blood sample for compatibility testing. -
Answers The sample must be labeled at the bedside
A recipient phenotypes as group O with the following Rh phenotype: D+C+c-E+e+.If this recipient is
transfused with red blood cells from six random group O D-positive donors, what Rh alloantibody could
this patient produce as a result of transfusion? - Answers anti-c
(Feedback: Although Rh phenotyping is not routinely performed, exposure to the c antigen may cause
the recipient to make anti-c because the recipient is negative for the antigen)
If the recipient was transfused within the last 3 months, how long from the time of collection can a
sample be used for the crossmatch? - Answers 3 days
Which of the following tests is not included in routine compatibility testing?
A) Direct antiglobulin test
B) ABO phenotyping
C) Antibody screen
D) D typing
A) Direct antiglobulin test
All of the following may be used to perform an antibody screen for an infant less than 4 months old
except: - Answers paternal serum
In which of the following situations can the crossmatch test be omitted? - Answers in a patient who has
recieved a massive transfusion within a 24-hour period (Feedback: The performance of a crossmatch for
a massively transfused patient may be omitted if the total patient volume has been exchanged (10 to 12
units of whole blood) within 24 hours)
What are the two components of the major crossmatch? - Answers Donor red cells and recipient serum
To what does the abbreviation "MSBOS" refer? - Answers Maximum blood order schedule
How long following transfusion must the recipient sample be stored? - Answers 7 days (Feedback: The
recipient's sample should be stored at 1 to 6 C for 7 days in case there is a transfusion reaction that
requires investigation)
Compatibility procedures will address all of the following except to: - Answers prevent antibody
formation (Feedback: The compatibility test may prevent the formation of anti-D, but all other antigens
are not matched)
To increase the sensitivity of the antibody screen in a compatibility test, what can be done? - Answers
Increase the serum to cell ratio.
Use an enhancement such as polyethylene glycol.
Extend the incubation time
Antibody screening of the recipient is performed as a component of compatibility testing to detect: -
Answers red cell alloantibodies (Feedback: The antibody screen detects alloantibodies that the recipient
made to red cell exposure from pregnancy or prior transfusions)
The following red cell antigen frequencies:
K
10%
E
30%
K
90%
P1
,80%
Which of the following red cell alloantibodies would be responsible for incompatible crossmatches with
one 1 of 10 random donor units? - Answers anti-K (Feedback: Anti-K is incompatible with 1 in 10 units of
red blood cells)
An infant less than 4 months old requires which procedures for compatibility testing? - Answers ABO
and D typing and antibody screen initially only; units released without additional testing if the screen is
negative (Feedback: An infant less than 4 months old does not make red cell antibodies and therefore
does not need to be checked with each transfusion. Initial screens detect antibodies made by the
mother)
In which phase of reactivity would rouleaux typically be detected in the screen? - Answers 37 C
(Feedback: In the screen, 37 C is typically where rouleaux is initially detected)
An antibody screen on a patient with a prior history of transfusion was negative. The crossmatch,
performed at immediate spin and antihuman globulin, was incompatible with 1 unit selected. The next
step in the investigation would be to: - Answers perform a direct antiglobulin test on the incompatible
unit (Feedback: The most likely reason for the incompatibility is that the blood unit has a positive direct
antiglobulin test or the patient has developed an antibody to a low-frequency antibody. If the direct
antiglobulin test is negative, testing the patient's serum against a selected cell panel of low-frequency
antigen positive cells should be performed)
Patient M.M. was admitted to the hospital with acute bleeding. Anti-E was detected in the patient's
serum. Four E-negative units of blood were crossmatched for the patient. The units were compatible at
immediate spin and following the antiglobulin test. After the antiglobulin test was performed, IgG
sensitized red cells gave a 2+ agglutination reaction. The proper interpretation of this 2+ agglutination
reaction is the: - Answers antihuman globulin washing procedures was adequate (Feedback: IgG-
sensitized red cells should be positive if adequate washing was performed and antihuman globulin
reagent was added)
A group O patient was crossmatched with group B red blood cells. What phase of the crossmatch will
first detect this incompatibility? - Answers Immediate spin (Feedback: ABO incompatibilities should be
detected on immediate spin)
When group O blood is not available for transfusion, what is the next alternative? - Answers None
(Feedback: Group O individual has both anti-A and anti-B present in serum, which is incompatible with
all blood groups other than group O)
The use of the electronic (computer) crossmatch is restricted to recipients who: - Answers do not have
clinically significant antibody (Feedback: The electronic (computer) crossmatch may be performed only
on patients who do not have or have a history of a clinically significant antibody)
The immediate spin or abbreviated crossmatch is an acceptable procedure if the recipient: - Answers
has no prior or existing clinically significant antibodies
, If an emergency exists and there is not enough time to perform a crossmatch for red cells, what is the
correct procedure? - Answers release group O, D-negative whole blood (Feedback: Group O D-negative
red blood cell units should be released and the crossmatch procedure completed as soon as possible)
For autologous units transfused within the collection facility, which part of the compatibility procedure
is not required? - Answers Antibody screen (Feedback: Autologous units are given to the donor and do
not require an antibody screen unless nonautologous units are also to be transfused)
Which of the following blood products requires a crossmatch to be performed before issuing? - Answers
Granulocyte concentrates that have more than 2 mL of red blood cells
(Feedback: Granulocytes may contain a significant amount of red blood cells because they are obtained
from the "buffy coat" layer during apheresis. These units would require crossmatching before release)
Feedback: Granulocytes may contain a significant amount of red blood cells because they are obtained
from the "buffy coat" layer during apheresis. These units would require crossmatching before release.
Select the correct statement regarding the collection of a blood sample for compatibility testing. -
Answers The sample must be labeled at the bedside
A recipient phenotypes as group O with the following Rh phenotype: D+C+c-E+e+.If this recipient is
transfused with red blood cells from six random group O D-positive donors, what Rh alloantibody could
this patient produce as a result of transfusion? - Answers anti-c
(Feedback: Although Rh phenotyping is not routinely performed, exposure to the c antigen may cause
the recipient to make anti-c because the recipient is negative for the antigen)
If the recipient was transfused within the last 3 months, how long from the time of collection can a
sample be used for the crossmatch? - Answers 3 days
Which of the following tests is not included in routine compatibility testing?
A) Direct antiglobulin test
B) ABO phenotyping
C) Antibody screen
D) D typing
A) Direct antiglobulin test
