Laboratory Best Practices

Compatibility testing

Neonates and infants < 4 months

Obtain neonatal and maternal transfusion history (including any fetal transfusions) for all admissions..

Obtain a maternal sample for initial testing where possible, in addition to the patient sample.

Red cell selection: no maternal antibodies present

Select appropriate group and correct neonatal specification red cells.

Group O D-negative red cells may be issued electronically without serological crossmatch.

If the laboratory does not universally select group O D-negative red cells for this age group, blood group selection should either be controlled by the LIMS or an IAT crossmatch should be performed using maternal or neonatal plasma to serologically confirm ABO compatibility with both mother and neonate.

Red cell selection: where there is maternal antibody

Select appropriate group red cells, compatible with maternal alloantibody/ies.

An IAT crossmatch should be performed using the maternal plasma.

If it is not possible to obtain a maternal sample it is acceptable to crossmatch antigen-negative units against the infant’s plasma.

Where paedipacks are being issued from one donor unit it is only necessary to crossmatch the first split pack.

Subsequent split packs from this multi-satellite unit can be automatically issued without further crossmatch until the unit expires or the infant is older than 4 months.

If packs from a different donor are required, an IAT crossmatch should be performed.

Infants and children ≥ 4 months

For infants and children from 4 months of age, pre-transfusion testing and compatibility procedures should be performed as recommended for adults.