Group and save identifies the blood type; crossmatch reserves specific units
Expansion
Group and save (group and screen)
- Determines the ABO and RhD group
- Antibody screen against a panel of red cells for atypical antibodies
- The sample is held, usually for 3 to 7 days, so units can be issued quickly if needed
- Requested when transfusion is possible but not expected
Crossmatch
- Actual units are reserved for the patient
- Electronic issue is used where the group is known from two samples and the antibody screen is negative, taking minutes
- Serological crossmatch, mixing patient plasma with donor cells, is required where antibodies are present, and takes considerably longer, sometimes hours or days if the antibody is unusual
Two samples: most services require the group confirmed on two separately taken samples before non-emergency issue of group specific blood, precisely to catch a mislabelled sample.
Emergency blood
| Urgency | Product |
|---|---|
| Immediate | O negative (or O positive for males and older women), uncrossmatched |
| ~15 minutes | Group specific, uncrossmatched |
| ~45 minutes | Fully crossmatched |
Sampling rules: identify the patient by asking them to state name and date of birth, check against the wristband, take the sample, and handwrite the label at the bedside from the wristband, immediately, before leaving the patient. Never pre-label, never use addressograph labels for the sample, and never take samples from two patients at once.
Wrong blood in tube is the commonest serious transfusion error, and ABO incompatible transfusion is a Never Event, presenting with fever, loin and chest pain, hypotension, haemoglobinuria and disseminated intravascular coagulation.