What is the primary purpose of a crossmatch in blood banking?

• To determine the patient's ABO blood type

• To detect antibodies that could cause hemolytic transfusion reactions

• To count red blood cells in the donor unit

• To measure hemoglobin levels

In a major crossmatch, what components are mixed together?

• Donor serum + recipient red cells

• Recipient serum + donor red cells

• Donor plasma + recipient plasma

• Recipient red cells + donor red cells

What does a positive crossmatch indicate?

• The transfusion is safe to proceed

• There is incompatibility between donor and recipient

• The blood type is O negative

• The sample needs to be recollected

Which of the following enhancement techniques may be used in crossmatching?

• Low ionic strength saline (LISS)

• Polyethylene glycol (PEG)

• Enzyme treatment

• All of the above

What is the minimum observation time for the immediate spin phase of a crossmatch?

• 5 seconds

• 15 seconds

• 1 minute

• 5 minutes

In emergency situations when there's no time for a complete crossmatch, what type of blood is typically given?

• Type-specific blood only

• O positive blood for all patients

• O negative blood (universal donor)

• AB positive blood (universal recipient)

What should be done if the crossmatch is incompatible but the antibody screen is negative?

• Proceed with transfusion anyway

• Investigate for ABO/Rh typing errors

• Use a different crossmatch method

• Report as contaminated sample

How long are crossmatch results typically valid?

• 24 hours

• 48 hours

• 72 hours

• 1 week

Which reagent is used in the antiglobulin test (AGT) phase of crossmatching?

• Anti-A serum

• Anti-B serum

• Anti-human globulin (AHG)

• Saline solution