Immunohematology C9

Why is antibody screening of the recipient performed as a component of compatibility testing?

Detects red cell alloantibodies

Detects irregular antigens on the recipient's red cells

Detects human leukocyte antigen antibodies

Detects incompatibilities with the donor's red cells

Detects red cell alloantibodies

What is the immunoglobulin class of antibodies detected in the immediate-spin crossmatch?

IgA

IgM

IgG

IgD

IgM

Select the correct statement regarding the collection of a blood sample for compatibility testing.

The sample must be labeled at the bedside.

The sample requires a new numeric identifier for the patient for each

admittance.

The sample may be labeled at any time in an emergency.

The sample does not require a means to identify the phlebotomist.

The sample must be labeled at the bedside.

A patient 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. What is the proper interpretation of this 2+-agglutination reaction?

Antihuman globulin washing procedure was adequate.

IgG-sensitized red cells spontaneously agglutinated.

Crossmatch was incompatible.

Patient's anti-E reacted with the IgG-sensitized red cells.

Antihuman globulin washing procedure was adequate.

Which of the following tests is not included in routine compatibility testing?

ABO phenotyping

Direct antiglobulin test

D typing

Antibody screen

Direct antiglobulin test

What are the two components of the major crossmatch?

Recipient red cells and donor serum

Donor red cells and recipient serum

Reverse ABO cells and recipient serum

Screening cells and donor serum

Donor red cells and recipient serum

A group O patient was crossmatched with group B red blood cells. What phase of the crossmatch will first detect this incompatibility?

Immediate-spin

37° C low-ionic strength solution

Indirect antiglobulin

None of them; unit is compatible

Immediate-spin

Select the item that compatibility procedures will not address.

Prevent formation of all red cell antibodies

Prevent life-threatening transfusion reactions

Maximize in vivo survival rate of red cells

Check ABO compatibility

Prevent formation of all red cell antibodies

A recipient is 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?

Anti-E

Anti-C

Anti-c

Anti-D

Anti-c

Given 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?

Anti-K

Anti-E

Anti-k

Anti-P1

Anti-K

Your blood bank mistakenly released a D-positive red blood cell unit that subsequently transfused to a patient who typed as D-negative. The patient had no history of a previous transfusion or pregnancy. Antibody detection testing was negative in pretransfusion testing. Predict the crossmatch result in this case.

Compatible at immediate-spin

Incompatible at immediate-spin only

Not necessary to perform

Incompatible at antihuman globulin only

Compatible at immediate-spin

An antibody screen on a patient with a prior history of transfusion was negative. The crossmatch was incompatible with 1 unit selected at AHG phase. What is the next step in the investigation?

Perform a prewarm procedure for crossmatching

Perform a direct antiglobulin test on the incompatible unit

Redraw the patient and begin a new crossmatch

Crossmatch a new unit and discard the incompatible unit

Perform a direct antiglobulin test on the incompatible unit

Which of the following blood products requires a crossmatch before issuing?

Group AB fresh frozen plasma that is transfused to a group O

Human leukocyte antigen-matched platelets

Cryoprecipitated AHF

Granulocyte concentrates that have more than 2 mL of red blood

cells

Granulocyte concentrates that have more than 2 mL of red blood cells

What compatibility testing procedures are required for an infant less than 4 months old?

Antibody screen with each unit released in a 48-hour period

ABO and D typing and antibody screen initially only; units released

without additional testing, if the screen is negative

Immediate-spin crossmatch with each unit released

Group O, D-negative units; no testing is necessary

ABO and D typing and antibody screen initially only; units released without additional testing, if the screen is negative

When is the immediate-spin or abbreviated crossmatch an acceptable procedure for the recipient?

No prior or existing clinically significant antibodies

Never been pregnant or transfused

Needs blood before a sample can be obtained

Using blood from a directed donation

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?

Release group O, D-negative whole blood.

Release group O, D-negative RBC units.

Release group AB fresh frozen plasma until the blood type is

performed.

Release ABO-compatible blood based on the patient's prior record

in the computer.

Release group O, D-negative RBC units.

How long following transfusion must the recipient's sample be stored?

5 days

7 days

10 days

14 days

7 days

When type O blood is not available for transfusion for a type O recipient, what is the next alternative?

Group A red blood cells

Group AB red blood cells

Washed group B red blood cells

None

None

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?

3 days

5 days

7 days

10 days

3 days

For autologous units transfused within the collection facility, which part of the compatibility procedure is not required?

ABO phenotyping

D phenotyping

Antibody screen

Transfusion history check

Antibody screen

Select the item that cannot be used to perform an antibody screen for an infant less than 4 months old.

Infant serum

Paternal serum

Maternal serum

Infant eluate

Paternal serum

Which reactivity phase of the screen would typically detect rouleaux?

4° C

15° C

37° C

Antihuman globulin

37° C

To what does the abbreviation "MSBOS" refer?

Monthly surgical blood order schedule

Minimum surgical blood order staffing

Maximum blood order schedule

Minimum safe blood order schedule

Maximum blood order schedule

What can be done to increase the sensitivity of the antibody screen in a compatibility test?

Extend the incubation time.

Increase the serum-to-cell ratio.

Use an enhancement such as polyethylene glycol.

All of the above are correct.

All of the above are correct.

The use of the electronic (computer) crossmatch is restricted to recipients who:

are group O.

do not have a clinically significant antibody.

have had successful transfusions in the past.

have transfusion history that has been documented in the computer.

do not have a clinically significant antibody.

A tube was received in the blood bank for crossmatching. The label was torn and the only information that was visible was the patient's last name and the medical record number. Which of the following is an acceptable procedure?

Request a recollection of the specimen.

Call the phlebotomist back to relabel the tube.

Reprint a label using the MRI as the identifier.

Use the tube since the MRI is visible.

Request a recollection of the specimen.

How many units of red blood cells are required to raise the hematocrit of a 70-kg nonbleeding adult man from 24% to 30%?

1

2

3

4

2

A 29-year-old female was admitted to the emergency room with severe bleeding. The blood type was group AB, D-negative. Six units of RBCs are ordered STAT. Of the following types available in the blood bank, which would be the most preferable for crossmatch?

AB, D positive

A, D negative

A, D positive

O, D negative

A, D negative

A donor unit with a positive DAT would cause reactions at what phase of the crossmatch?

Immediate-spin

Antiglobulin

None; it would be compatible

All phases

Antiglobulin