CH7: Immunohematology and blood transfusion medicine

1. Which immunodominant sugar confers A antigen

specificity?

a. D-Galactose

b. L-Fucose

c. N-Acetylgalactosamine

d. Both A and C

c. N-Acetylgalactosamine

2. If a patient has an A2 ABO type, which of the following

statements is true?

a. The patient's red cells will react with anti-A1 lectin

b. The patient's serum will react with A2 cells

c. The patient's red cells will react with anti-A2 lectin

d. The patient's serum will react with A1 cells if

anti-A1 is present

d. The patient's serum will react with A1 cells if

anti-A1 is present

3. Which genotype confers the Bombay blood type?

a. Hh

b. hh

c. Sese

d. Lele

b. hh

4. Which genes encode for Rh antigens?

a. RHDCE

b. RHD

c. RHCE

d. Both b and c

d. Both b and c

5. Testing for the D antigen was conducted at the IAT

phase. A control was included in the testing. Both

the patient's red cells and the control tube reacted

at 4+. How would you interpret this test?

a. The test is invalid because the control tube was

positive

b. The patient is D positive

c. The patient is D negative

d. The test should be repeated and the control tube

omitted

a. The test is invalid because the control tube was

positive

6. Of the red cells listed, which has the most D antigen

present?

a. Rh null

b. D positive

c. dce/dce

d. D--

d. D--

7. Which is true of the Duffy blood group system?

a. Antigens are resistant to enzyme treatment

b. Antibodies never show dosage

c. Fya and Fyb are codominant alleles

d. The majority of whites are Fy(a-b-)

c. Fya and Fyb are codominant alleles

8. Which antibody is typically considered to be an autoantibody

if found in the serum of an adult?

a. Anti-K

b. Anti-I

c. Anti-D

d. Anti-Fya

b. Anti-I

9. Which reagent destroys all of the Kell blood group

system antigens?

a. DTT

b. Chloroquine diphosphate

c. AHG

d. LISS

a. DTT

10. Which is true of antibodies to Kidd blood group system

antigens?

a. They are enhanced by enzymes

b. Titers can quickly drop in patients

c. Both A and B

d. None of the above

c. Both A and B

11. Which of the following is true of the Lewis system?

a. Lewis antigens are found on type II precursor cells

b. Lewis antigens are well developed at birth

c. Antibodies to Lewis antigens always cause HTRs

d. Antibodies to Lewis antigens rarely cross the

placenta

d. Antibodies to Lewis antigens rarely cross the

placenta

12. Which of the following is true of antibodies to MNS

blood group system antigens?

a. Anti-U is directed at a high-incidence antigen

b. Anti-N is commonly found

c. Anti-M is always clinically significant

d. Anti-S is reactive with enzyme-treated cells

a. Anti-U is directed at a high-incidence antigen

13. Which of the following antibodies is classified as

"biphasic" and an autoantibody?

a. Anti-B

b. Anti-P

c. Anti-H

d. Anti-Lea

b. Anti-P

14. You have performed an antibody screen using the

tube method. All three screening cells tested negative.

The Coombs check cells in all three tubes are also

nonreactive. What should you do?

a. Respin the tubes and reread them

b. Report the antibody screen as negative

c. Repeat the antibody screen

d. Perform an antibody identification panel

c. Repeat the antibody screen

15. An antibody panel has six 2+ reactive cells at AHG

phase. Panel testing using enzyme-treated cells

showed no reactivity. Which is the most likely antibody

that is present?

a. Anti-Fya

b. Anti-e

c. Anti-k

d. Anti-Lua

a. Anti-Fya

16. A patient has a currently nonreactive antibody screen

but has a history of anti-Jka in the patient file. Which

type of crossmatch must be performed on this patient?

a. Immediate spin crossmatch

b. IAT crossmatch

c. Electronic crossmatch

d. Both a and c

b. IAT crossmatch

17. A recently transfused patient has a 3+ reactive DAT

with anti-IgG. Which procedure should be used to

identify the specificity of the IgG antibody attached

to the red cells?

a. Adsorption

b. Neutralization

c. Titration

d. Elution

d. Elution

18. An O-negative mother gave birth to an O-positive

baby. Her rosette test was positive. Which of the following

is true?

a. The test is invalid because of the mother's

ABO type

b. A Kleihauer-Betke test should be performed to

quantify the fetal maternal hemorrhage

c. The mother should be given a 300-mg dose

of RhIG

d. A weak D test should be performed on the baby

b. A Kleihauer-Betke test should be performed to

quantify the fetal maternal hemorrhage

19. In which of the following settings are platelet transfusions

not indicated?

a. Thrombotic thrombocytopenic purpura

b. Immune thrombocytopenic purpura with severe

intracranial hemorrhage

c. Massive transfusion

d. Vascular catheter placement, platelet count

24,000/mL

e. Brain biopsy, platelet count 62,000/mL

a. Thrombotic thrombocytopenic purpura

20. An obstetric patient presents to the hospital with

marked vaginal bleeding and severe lower abdominal

pain. During placement of an intravenous catheter,

she was noted to have marked oozing. She is diagnosed

with disseminated intravascular coagulation

as a complication of her primary problem. She is

given cryoprecipitate and fresh frozen plasma before

going to the operating room. What element of cryoprecipitate

is important in treating this patient?

a. Factor I

b. Factor II

c. Factor VIII:c

d. Factor VIII:vWF

e. Factor XIII

a. Factor I

21. A patient's ABO blood type is determined by which

of the following?

a. Genetic inheritance and environmental factors

b. Genetic inheritance

c. Environmental factors

d. Immune function

e. Maternal blood type

b. Genetic inheritance

22. A trauma patient with type AB is seen at a rural hospital.

The hospital only has 3 units of type AB RBCs.

What blood type of RBCs can the patient receive as

an alternative?

a. Type O

b. Type B

c. Type A

d. None of the above

e. All of the above

e. All of the above

23. A genetic state in which no detectable trait exists is

called:

a. Recessive

b. Dominant

c. Incomplete dominance

d. Amorph

d. Amorph

24. Most blood group antigens are expressed as a result

of which of the following?

a. Autosomal recessive inheritance

b. X-linked dominant inheritance

c. Y-linked recessive inheritance

d. Autosomal codominant inheritance

d. Autosomal codominant inheritance

25. What blood type is not possible for the offspring of

AO and BO parents?

a. AB

b. A or B

c. O

d. All are possible

d. All are possible

26. How many molecules of IgM are needed to fix

complement?

a. 1

b. 2

c. 3

d. 4

a. 1

27. For lysis of red blood cells to occur after antigen-

antibody reaction, which compound is required?

a. Albumin

b. Glucose-6-phosphate dehydrogenase (G6PD)

c. Complement

d. Antihuman globulin (AHG)

c. Complement

28. An end-point of tube testing other than agglutination

that must also be considered a positive reaction is

called:

a. Clumping

b. Mixed field

c. Hemolysis

d. Microscopic

c. Hemolysis

29. Mixed-field (mf) agglutination can be observed

in the:

a. DAT on a person undergoing delayed hemolytic

transfusion reaction

b. IAT result of a patient who has anti-Lea

c. DAT on a patient on high doses of penicillin

d. Typing result with anti-A of a patient who is A2

subgroup

a. DAT on a person undergoing delayed hemolytic

transfusion reaction

30. In which situation(s) may the ABO serum grouping

not be valid?

a. The patient has hypogammaglobulinemia

b. IgM antibodies are present

c. Cold autoantibodies are present

d. All of the above

d. All of the above

31. If you knew the DAT is positive, what would you

expect the Rh control to be when doing a weak D test

through AHG?

a. Negative

b. Positive

c. Mixed field

d. Hemolysis at 37 C would be seen

b. Positive

32. How can IgG antibodies be removed from red cells?

a. Elution

b. Adsorption

c. Prewarming

d. Neutralization

a. Elution

33. Testing needs to be done with an antiserum that is

rarely used. The appropriate steps to take in using this antiserum include following the manufacturer's

procedure and:

a. Performing a cell panel to be sure that the antiserum

is performing correctly

b. Performing the testing on screen cells

c. Testing in duplicate to ensure the repeatability of

the results

d. Testing a cell that is negative for the antigen and

one that is heterozygous for the antigen

d. Testing a cell that is negative for the antigen and

one that is heterozygous for the antigen

(see pic) 34. Based on the following antigram, which cell is heterozygous

for M?

a. Cell 1

b. Cell 2

c. Cell 3

d. None of the above

a. Cell 1

35. Which antibody can be neutralized with a specific

reagent?

a. Anti-D

b. Anti-Jka

c. Anti-M

d. Anti-Lea

d. Anti-Lea

36. Group O red blood cells are used as a source of commercial

screening cells because:

a. Anti-A is detected using group O cells

b. Anti-D reacts with most group O cells

c. Weak subgroups of A react with group O cells

d. ABO antibodies do not react with group O cells

d. ABO antibodies do not react with group O cells

37. The use of EDTA samples for the direct antiglobulin

test prevents activation of the classical complement

pathway by:

a. Causing rapid decay of complement proteins

b. Chelating Mg2+ ions, preventing assembly of C6

c. Chelating Ca2+ ions, preventing assembly of C1

d. Preventing chemotaxis

c. Chelating Ca2+ ions, preventing assembly of C1

38. Check (Coombs control) cells are:

a. Added to every negative antiglobulin test

b. Added to negative direct antiglobulin tests only

c. Used to confirm a positive Coombs' reaction

d. Coated with both IgM and C3d

a. Added to every negative antiglobulin test

39. What type(s) of red cells is(are) acceptable to transfuse

to an AB-negative patient?

a. A negative, B negative, AB negative, O negative

b. O negative only

c. AB negative only

d. AB negative, A negative, B negative only

a. A negative, B negative, AB negative, O negative

40. A nonbleeding adult of average height and weight

with chronic anemia is transfused with 2 units of

red blood cells. The pretransfusion Hgb is 7.0 g/dL.

What is the expected posttransfusion Hgb?

a. 8 g/dL

b. 9 g/dL

c. 10 g/dL

d. 11 g/dL

b. 9 g/dL

41. An IgA-deficient patient with clinically significant

anti-IgA requires which of the following?

a. Leukocyte-reduced fresh frozen plasma

b. CMV-seronegative RBCs

c. Irradiated RBCs and platelets

d. Washed RBCs

d. Washed RBCs

42. Anti-H will react weakest with blood from a person

with _____________.

a. Group O

b. Group A1

c. Group A2

d. Group A2B

b. Group A1

43. Which of the following antibodies do not match the

others in terms of optimal reactive temperature?

a. Anti-Fya

b. Anti-M

c. Anti-K

d. Anti-S

b. Anti-M

44. What antibody can an R1r patient make if transfused

with R2R2 blood?

a. Anti-D

b. Anti-C

c. Anti-E

d. Anti-c

e. Anti-e

c. Anti-E

45. What is the probability of finding blood negative for

the Jka and Fya antigens (23% of population is Jk

[a-] and 34% of population is Fy[a-])?

a. 5.1%

b. 51%

c. 7.8%

d. 78%

c. 7.8%

(see pic) 46. If the following patient's RBCs were tested against

anti-H lectin and did not react, this person would

be identified as a(an):

a. Acquired B

b. Secretor

c. Oh phenotype

d. Subgroup of A

c. Oh phenotype

47. If a person has the genetic makeup Hh, AO, LeLe,

sese, what substance will be found in the secretions?

a. A substance

b. H Substance

c. Lea substance

d. Leb substance

c. Lea substance

48. Before A and B antigens can be expressed, the precursor

substance must have the terminal sugar

_______________.

a. d-Galactose

b. N-Acetylgalactosamine

c. Glucose

d. L-Fucose

d. L-Fucose

49. A white female's RBCs gave the following

reactions: D+, C+, E-, c+, e+. The most probable

Rh genotype is:

a. DCe/Dce

b. DCe/dce

c. DCe/DcE

d. Dce/dCe

b. DCe/dce

50. If a D-positive person makes anti-D, this person is

most likely:

a. Partial D

b. D negative

c. Weak D as position effect

d. Weak D because of transmissible genes

a. Partial D

51. A serum containing anti-k is not frequently encountered

because of which of the following?

a. People who lack the k antigen are rare

b. People who possess the k antigen are rare

c. The k antigen is not a good immunogen

d. Kell-null people are rare

a. People who lack the k antigen are rare

52. A characteristic of the Xga antigen is that the Xga

antigen:

a. Has a higher frequency in women than in men

b. Has a higher frequency in men than in women

c. Is enhanced by enzymes

d. Is usually a saline reacting antibody

a. Has a higher frequency in women than in men

53. Which of the following is a characteristic of the Kidd

system antibodies?

a. The antibodies are usually IgM

b. The corresponding antigens are destroyed by

enzymes

c. The antibodies are usually strong and stable during

storage

d. The antibodies are often implicated in delayed

hemolytic transfusion reactions

d. The antibodies are often implicated in delayed

hemolytic transfusion reactions

54. Anti-E will react with which of the following cells?

a. RoRo

b. R1R1

c. R2R2

d. rr

c. R2R2

55. Which statement is not true concerning anti-Fya and

anti-Fyb?

a. Are clinically significant

b. React well with enzyme-treated panel cells

c. Cause hemolytic transfusion reactions

d. Cause a generally mild hemolytic disease of the

newborn

b. React well with enzyme-treated panel cells

56. Which of the following antibodies can be neutralized

with pooled human plasma?

a. Anti-Hy and anti-Ge:1

b. Anti-Cha and anti-Rga

c. Anti-Coa and anti-Cob

d. Anti-Doa and anti-Jsb

b. Anti-Cha and anti-Rga

57. Donors who have received RBC transfusion within

the last 12 months are deferred because:

a. Blood could transmit hepatitis or HIV

b. Donor red cell hemoglobin level may be too low

c. Donor health would prohibit the donation

process

d. There will be two cell populations in this

donor

a. Blood could transmit hepatitis or HIV

58. Autologous presurgical donations are not allowed

for which of the following patients?

a. Weigh less than 100 lb

b. Under the age of 14

c. With hemoglobin of 13 g/dL

d. With bacteremia

d. With bacteremia

59. Which of the following viruses resides exclusively in

leukocytes?

a. HCV

b. HBV

c. CMV

d. HIV

c. CMV

60. Which product is least likely to transmit hepatitis?

a. Cryoprecipitate

b. Plasma protein fraction

c. RBC

d. Platelets

b. Plasma protein fraction

61. In preparing platelets from a unit of whole blood, the

correct order of centrifugation is:

a. Hard spin followed by a hard spin

b. Light spin followed by a light spin

c. Light spin followed by a hard spin

d. Hard spin followed by a light spin

c. Light spin followed by a hard spin

62. Which antibody could cause hemolytic disease of the

fetus and newborn?

a. Anti-I

b. Anti-K

c. Anti-Lea

d. Anti-N

b. Anti-K

63. A group A, D-negative obstetric patient with

anti-D (titer 256) is carrying a fetus who needs an

intrauterine transfusion. The blood needed

should be:

a. Group A, D-negative RBC

b. Group A, D-negative whole blood

c. Group O, D-negative RBC

d. Group O, D-negative whole blood

c. Group O, D-negative RBC

64. Which of the following mothers should receive

RhIG?

a. A-negative mother; O-negative baby; no prenatal

care, anti-D in mother

b. AB-negative mother; B-positive baby; anti-D

in mother

c. O-negative mother; A-positive baby; no anti-D

in mother

d. A-positive mother; A-positive baby; no anti-D

in mother

c. O-negative mother; A-positive baby; no anti-D

in mother

65. How many doses of RhIG are indicated for a

Kleihauer-Betke reading of 0.6%?

a. 1

b. 2

c. 3

d. 4

b. 2

66. What should be done first if a mother types as O and

the baby types as AB?

a. Report the results with no further testing

b. Try to get a sample from the father

c. Recheck all labels, get new samples, if necessary,

and retest

d. Retype using all new reagents

c. Recheck all labels, get new samples, if necessary,

and retest

67. A newborn has a positive DAT.What is the best procedure

to determine the antibody causing a positive

DAT in this newborn?

a. An antibody titer on the mother's serum

b. An antibody panel on the mother's serum

c. An antibody panel performed on the eluate of the

mother's cells

d. An antibody panel performed on the eluate of the

baby's cells

b. An antibody panel on the mother's serum

68. Which of the following is(are) an example(s) of a

record-keeping error?

a. Use of correction fluid or tape

b. Using pencil

c. Documentation after the fact

d. All of the above

d. All of the above

69. Which of the antigens below is considered low

incidence?

a. Fya

b. S

c. C

d. Kpa

d. Kpa

70. Which of the antigens below is considered high

incidence?

a. Fyb

b. Vel

c. E

d. S

b. Vel

71. In performing tube testing, you see many mediumsized

agglutinates in a clear background. How would

you grade this reaction?

a. 2+

b. 1+

c. 4+

d. 3+

a. 2+

72. Of the following, which genotypes would result in

the B phenotype?

a. BB

b. AB

c. BO

d. a and b

e. a and c

e. a and c

73. How would you interpret the following reactions?

Forward Type Reverse Type

Anti-A Anti-B A1 Cells B Cells

0 0 4+ 4+

a. Blood type A

b. Blood type O

c. Blood type B

d. Blood type AB

b. Blood type O

74. Noting these reactions, if they patient needed blood

now, what type of blood should be transfused?

Forward Type Reverse Type

Anti-A Anti-B A1 Cells B Cells

4+ 0 1+ 4+

a. Blood type A

b. Blood type O

c. Blood type A2

d. Blood type A

b. Blood type O

75. Blood group antibodies made by type A and type B

people are predominantly which class?

a. IgE

b. IgA

c. IgG

d. IgM

d. IgM

76. Based on these reactions,what should be the next step?

Forward Type Reverse Type

Anti-A Anti-B A1 Cells B Cells

4+ 0 1+ 4+

a. Test the serum with A2 cells

b. Report the patient as type A

c. Test the cells with anti-A1 lectin

d. Both a and c

e. Request a new specimen

d. Both a and c

77. A "directed donor" unit of blood is defined as a unit

of blood from a person who gives blood for:

a. Relief of polycythemia or other blood disorder

b. His or her specific use only

c. First-degree blood relative

d. Another person he or she has specified

d. Another person he or she has specified

78. Before the patient can receive a directed donation

unit, the patient requires which of the following tests

to be completed?

a. Type and screen only

b. Type and screen and compatibility testing

c. Retype of patient and donor unit

d. No additional testing is required

b. Type and screen and compatibility testing

79. An 18-year-old female with a hematocrit of 38%,

temperature of 37 C, and blood pressure of 175/

90 mm Hg presents for whole blood donation. Based

on this information, would you accept, permanently

defer (PD), or temporarily defer (TD) the donor?

a. Accept

b. TD, blood pressure is too high for a person of

her age

c. TD, temperature is too high

d. PD, for all values listed

a. Accept

80. A 63-year-old man with a hemoglobin value of

130 g/dL and pulse of 80 beats/min, who received

human pituitary growth hormone (PGH) when he

was 10 years old, presents for whole blood donation.

Based on this information, would you accept, permanently

defer (PD,) or temporarily defer (TD) the donor?

a. Accept the donor

b. TD, because of the human PGH

c. PD, because of the human PGH

d. PD, because of the high hemoglobin value

c. PD, because of the human PGH

81. A 38-year-old female weighing 153 lb, who received

the rubella vaccine 2 months previously, presents to

donate whole blood. She also received 2 units of

packed cells after the delivery of her eighth child

8 weeks ago. Based on this information, would you

accept, permanently defer (PD), or temporarily defer

(TD) the donor?

a. Accept the donor

b. TD because of the packed cells 8 weeks ago

c. PD because of receiving blood products

d. TD because of the rubella vaccine

b. TD because of the packed cells 8 weeks ago

82. A22-year-old female witha cousinwithAIDSwhohad

taken aspirin the day before and with needle marks on

both arms presents to donate whole blood. Based on

this information,would you accept, permanently defer

(PD), or temporarily defer (TD) the donor?

a. PD, needle marks on both arms

b. TD, needle marks on both arms

c. PD, cousin with AIDS

d. TD, because of the aspirin

a. PD, needle marks on both arms

83. Each unit of blood must be tested for all of the following

except:

a. Anti-HIV 1/2

b. HBsAg

c. Anti-HCV

d. Antigen to HCV

d. Antigen to HCV

84. The principle of the HBsAg test is to detect which of

the following?

a. Antigen in patient's plasma

b. Antigen on the patient's RBCs

c. Antibody in patient's serum

d. Antigen and antibody in patient's serum

a. Antigen in patient's plasma

85. Cryoprecipitate is prepared by first thawing:

a. Fresh frozen plasma at 1 to 6 C, and then doing

a cold centrifugation to pack the cryoprecipitate

to the bottom so the plasma may be removed

b. Fresh frozen plasma at room temperature, then

placing in the freezer for 2 hours, then centrifuging

and removing the cryoprecipitate

c. Cryoprecipitate at 1 to 6 C, then pooling the

thawed cryoprecipitate in batches of 10 units,

then quickly refreezing

d. Cryoprecipitate at room temperature, then centrifugation

in the cold to concentrate the cryoprecipitate

to the bottom before adding more plasma

to reconstitute

a. Fresh frozen plasma at 1 to 6 C, and then doing

a cold centrifugation to pack the cryoprecipitate

to the bottom so the plasma may be removed

86. Platelets must be kept in constant motion for which

of the following reasons?

a. Maintain the pH so the platelets will be alive

before transfusion

b. Keep the platelets in suspension and prevent

clumping of the platelets

c. Mimic what is going on in the blood vessels

d. Preserve the coagulation factors and platelet

viability

a. Maintain the pH so the platelets will be alive

before transfusion

87. After thawing and pooling cryoprecipitate for transfusion

to a patient, the product should be stored at:

a. Room temperature

b. 1 to 6 C

c. 37 C

d. 0 C

a. Room temperature

88. Fresh frozen plasma must be thawed at which

temperature?

a. 1 to 6 C

b. Room temperature

c. 37 C

d. 40 C or higher

c. 37 C

89. Frozen red blood cells are prepared for transfusion

by thawing at:

a. Room temperature and then washing with saline

b. 37 C in a water bath and then washing with different

concentrations of saline

c. 37 C control incubator and then mixing well

before transfusion

d. 1 to 6 C for 2 days and then washing with different

concentrations of dextrose

b. 37 C in a water bath and then washing with different

concentrations of saline

90. Which is the most likely reason frozen deglycerolized

red blood cells would be used?

a. A patient with antibodies to a high-frequency

antigen

b. Pregnant women requiring intrauterine

transfusions

c. Emergency transfusion situations

d. Group AB Rh-negative patients

a. A patient with antibodies to a high-frequency

antigen

91. One indication for transfusion of thawed/pooled

cryoprecipitate would be replacement of which of

the following?

a. Factor X in hemophiliacs

b. Factor VIII in massively transfused patients

c. Fibrinogen

d. Volume

c. Fibrinogen

92. A contraindication for transfusing red blood cells to

a patient is if the patient:

a. Is massively bleeding

b. Has well-compensated anemia

c. Has bone marrow failure

d. Has decreased red blood cell survival

b. Has well-compensated anemia

93. Concerning the component and the required quality

control results, which of the following is a true

statement?

a. FFP must have 80 international units of fibrinogen

in 7 units tested

b. Cryoprecipitate must have 80 international units

of factor VIII

c. Leukocyte-reduced red blood cells must have

fewer than 3.3x1011 WBCs in each unit

d. Platelets must have no red blood cells

b. Cryoprecipitate must have 80 international units

of factor VIII

94. Fresh frozen plasma must be stored at:

a. Colder than -18 C for no longer than 1 year

from donation

b. Colder than -38 C for no longer than 1 year

from donation

c. Exactly -18 C for no longer than 1 year from

donation

d. -18 C to -38 C for up to 10 years from

donation

a. Colder than -18 C for no longer than 1 year

from donation

95. The storage temperature for packed red blood cells is

_______________.

a. 1 to 10 C

b. 1 to 4 C

c. 1 to 6 C

d. 20 to 25 F

c. 1 to 6 C

96. Platelets made from a single whole blood donation

should contain which of the following?

a. 3x1011 platelets in 90% of samples

b. 3.3x109 platelets in 75% of samples

c. 5.5x1010 platelets in 90% of samples

d. 10x1010 platelets in 75% of samples

c. 5.5x1010 platelets in 90% of samples

97. Frozen red blood cells must be stored at

__________________.

a. 180 C or less

b. 18 C or less

c. 32 C or less

d. 65 C or less

d. 65 C or less

98. The temperature for incubation of the indirect antiglobulin

test (IAT) should be ____________.

a. 24 C

b. 6 C

c. 37 C

d. 3710 C

c. 37 C

99. The temperature of a blood refrigerator without a

continuous recording device should be recorded:

a. Daily

b. Every 4 hours

c. Once every 24 hours

d. Every 30 minutes

b. Every 4 hours

100. When should quality control be performed on routine

blood typing reagents?

a. At the beginning of each shift

b. Once daily

c. Weekly

d. Only when opening a new vial

b. Once daily