What it means
Red blood cells carry markers (antigens) on their surface. The ABO system names four groups: A, B, AB and O. The Rh system adds positive (the D antigen is present) or negative (it is absent). Blood given in a transfusion must match, or the client's antibodies attack the donor cells. Type O negative red cells can be given to almost anyone in an emergency; type AB positive clients can receive red cells of any type.
For the nurse
A type and crossmatch is drawn before a transfusion. In pregnancy, an Rh-negative client is given Rh immune globulin as ordered, to protect a future Rh-positive baby.
At a glance
| Abbreviations | T&C (type and crossmatch); T&S (type and screen) |
|---|---|
| Spanish | grupo sanguíneo |
| Also written | ABO blood type, ABO typing, blood group, blood typing, blood types, blood groups, blood-type |
Related terms
blood transfusion
Giving blood, or a part of blood, from a donor into a person's vein.
red blood cell
A blood cell that carries oxygen from the lungs to the body's tissues; also called an erythrocyte.
blood product
Any part of donated blood prepared for transfusion, such as red cells, plasma or platelets.