CMT CMT Blood Banking and Transfusion Medicine 1 — Questions and Answers
Question 1: Which ABO blood group is considered the 'universal donor' for red blood cell transfusions?
- AB
- A
- B
- O (Correct answer)
Correct answer: O
Group O red blood cells lack A and B antigens, making them compatible with recipients of any ABO blood group in emergency situations.
Question 2: The Rh blood group antigen most commonly responsible for hemolytic disease of the fetus and newborn (HDFN) is:
- Rh(c)
- Rh(D) (Correct answer)
- Rh(E)
- Rh(e)
Correct answer: Rh(D)
The D antigen is the most immunogenic Rh antigen; Rh(D)-negative mothers who form anti-D antibodies pose the greatest risk for severe HDFN.
Question 3: A direct antiglobulin test (DAT) is used to detect:
- Antibodies in the patient's serum
- Antibodies coating the patient's red blood cells in vivo (Correct answer)
- ABO blood group
- Platelet antibodies
Correct answer: Antibodies coating the patient's red blood cells in vivo
The DAT (direct Coombs test) uses anti-human globulin to detect IgG antibodies or complement already bound to circulating red blood cells.
Question 4: Platelet concentrates should be stored at:
- 1–6°C with gentle agitation
- 20–24°C with continuous agitation (Correct answer)
- –80°C frozen
- –20°C frozen
Correct answer: 20–24°C with continuous agitation
Platelets must be stored at room temperature (20–24°C) with constant agitation to maintain viability and prevent aggregation; refrigeration activates and damages platelets.
Question 5: Which crossmatch technique detects most clinically significant alloantibodies that may cause hemolytic transfusion reactions?
- Immediate spin crossmatch only
- Room temperature saline crossmatch
- Antihuman globulin (AHG) crossmatch (Correct answer)
- Electronic crossmatch
Correct answer: Antihuman globulin (AHG) crossmatch
The AHG crossmatch (indirect Coombs phase) detects IgG alloantibodies that react at 37°C and are associated with hemolytic reactions.
Question 6: Fresh frozen plasma (FFP) is indicated for:
- Iron deficiency anemia
- Replacement of coagulation factors in a bleeding patient with multiple factor deficiencies (Correct answer)
- Thrombocytopenia
- Hypogammaglobulinemia
Correct answer: Replacement of coagulation factors in a bleeding patient with multiple factor deficiencies
FFP contains all coagulation factors and is indicated for bleeding patients with documented factor deficiencies, liver disease-related coagulopathy, or massive transfusion.
CMT CMT Blood Banking and Transfusion Medicine 1
Which ABO blood group is considered the 'universal donor' for red blood cell transfusions?