Medical Laboratory Technician Blood Bank and Transfusion Questions and Answers

Question 1

A patient's antibody screen is positive.
The antibody identification panel shows reactivity with all panel cells, and the auto-control is also positive.
All reactions are occurring at the AHG phase.
Which of the following is the MOST likely cause of these results?

Accepted Answer

A warm autoantibody

Answer

A cold autoantibody

Answer

Multiple alloantibodies

Answer

An antibody to a high-prevalence antigen

Question 2

A unit of Red Blood Cells is issued from the blood bank at 08:00 for a routine transfusion. At 08:20, the nurse calls to report that the patient's IV has failed and the transfusion has not been started. The unit has been stored in a transport cooler with appropriate coolant packs. What is the correct course of action?

Accepted Answer

Return the unit to the blood bank immediately for proper storage.

Answer

Discard the unit immediately because it has been out of the blood bank for over 15 minutes.

Answer

Tell the nurse to keep the unit at the bedside until a new IV is established, as long as it is within 4 hours.

Answer

Begin the transfusion as soon as a new IV is started, regardless of the time.

Question 3

Which of the following blood components must be stored at 20-24°C with continuous, gentle agitation?

Accepted Answer

Platelets

Answer

Fresh Frozen Plasma (FFP)

Answer

Red Blood Cells (RBCs)

Answer

Cryoprecipitate

Question 4

During a pretransfusion compatibility test, a medical laboratory technician finds that the patient's ABO/Rh type is A positive, and the antibody screen is negative. The crossmatch is performed with an A positive donor unit. The immediate spin crossmatch is incompatible (4+). What is the MOST likely cause of this discrepancy?

Accepted Answer

The patient has an A2 subtype with the presence of anti-A1.

Answer

The patient has an antibody to a low-prevalence antigen present on the donor's red cells.

Answer

The donor unit is incorrectly labeled and is actually group B.

Answer

The patient has a cold-reacting alloantibody not detected by the screen.

Question 5

A transfusion reaction workup is initiated on a patient who developed fever, chills, and flank pain 15 minutes into a red blood cell transfusion. The initial laboratory investigation includes a clerical check, a visual check for hemolysis in the post-transfusion specimen, and a Direct Antiglobulin Test (DAT). Which of these findings would most strongly suggest an acute hemolytic transfusion reaction?

Accepted Answer

Pink or red plasma in the centrifuged post-transfusion specimen.

Answer

A clerical error discovered on the patient's wristband.

Answer

A negative DAT on the post-transfusion specimen.

Answer

The patient's temperature increased by 1°C.

Question 6

What is the primary purpose of irradiating cellular blood components?

Accepted Answer

To prevent transfusion-associated graft-versus-host disease (TA-GVHD).

Answer

To prevent bacterial contamination of the unit.

Answer

To extend the shelf-life of Red Blood Cells.

Answer

To inactivate viruses such as CMV and HIV.