Type and screen
Background
- Determines patient blood type (ABO and Rh) and screens for unexpected antibodies
- Required before transfusion of blood products
Components
- ABO typing (A, B, AB, O)
- Rh (D) typing (positive or negative)
- Antibody screen: tests for clinically significant antibodies that could cause transfusion reactions
Interpretation
- Negative antibody screen: crossmatch-compatible blood can be issued quickly
- Positive antibody screen: requires antibody identification and compatible unit selection (may delay transfusion)
- In emergent hemorrhage, do not wait for type and screen: use O-negative (premenopausal women) or O-positive (all others) uncrossmatched blood
- Type and crossmatch is a further step that tests patient serum against specific donor units