For whole blood a donation of 450 mL±10% is required to ensure the final red cell component meets specification. No more than 15% of the estimated blood volume should be taken during any one donation. In general 470–475 mL of blood, excluding samples, is collected into the main pack.
Attention must be paid during apheresis to the ECV in order to avoid rendering the donor significantly hypovolaemic. Consideration must be given to the following factors:
For any single apheresis procedure, the final collection volume should not exceed 15% of the total blood volume (TBV) excluding anticoagulant (see Appendix l).
During apheresis procedures the ECV should not exceed 15% TBV (excluding anticoagulant). Some procedures may result in a total ECV of as much as 1 litre. The procedure may need to be adjusted to suit each individual donor’s safety tolerance limits. Special considerations should be given during intermittent flow apheresis procedures (see Appendices I, II and III). TBV can be estimated using the Nadler formula (see Appendix I).3
ECV is the total volume of blood and plasma removed from the donor at any time. It includes all blood and plasma in collection packs and contained within the machine harness (volumes contained within the collection harness can be obtained by reference to manufacturers’ manuals).
Anticoagulant ratio during collection influences the volume of anticoagulant in collected plasma, e.g. anticoagulant in 1:12 ratio forms 14% of the final volume collected in a donor with a haematocrit of 45% (see Appendix II).