Platelets

Asset 12a-Apheresis Platelets.jpgAn apheresis machine separates anticoagulated blood into components with retention of the platelets and a portion of plasma to create a standard adult dose of apheresis plateletes. The remaining elements may be returned to the donor. When requested, an apheresis platelet unit can be further divided into four packs of equal volume to produce  paediatric apheresis platelet components. This is to reduce donor exposure for small paediatric transfusions and to minimise product wastage.

An adult dose of platelets derived from whole blood is obtained from a pool of buffy coats from four ABO identical donors and is resuspended in a nutrient additive solution to produce a pooled platelet component.

Both apheresis and pooled platelets are leucodepleted during  or soon after collection and they are also irradiated before release from the Blood Service, unless other specific arrangements have been made with the receiving laboratory/institution.

Platelets can be stored for 5 days after collection at 20 - 24º C with gentle agitation. Platelets can be irradiated at any stage during their 5 day storage and thereafter can be stored up to their normal shelf life of 5 days after collection.
 

Typical unit content and specifications

Information is based on the typical unit content (mean ± 1 SD) from Blood Service data (1 January to 31 December 2016 inclusive) and acceptable specification limits (in parentheses).

Volume (mL)
181 ± 12 (100–400)
Platelet count (10/unit)
290 ± 39 (> 200 to < 510)
pH 
6.9 ± 0.3 (6.4–7.4)
Leucocyte count (106 /unit)
0.2 ± 0.1 (< 1.0)
Volume (mL)
51 ± 1 (40-60)
Platelet count (10/unit)
80 ± 10 (> 60)
pH 
6.7 ± 0.3 (6.4-7.4)
Leucocyte count (10/unit) (in the starting component, ie, prior to splitting)
0.2 ± 0.1 (< 1.0)
Volume (mL)
334 ± 14 (> 160)
Platelet count (10/unit)
268 ± 38 (> 240)
pH 
7.0 ± 0.1 (6.4–7.4)  
Leucocyte count (10/unit)
0.33 ± 0.01 (< 0.8)

 

Availability

Platelets are available in all ABO groups and RhD positive and negative groups. Group AB are manufactured on request.
 

Modifications

Apheresis platelets can be modified as phenotyped, CMV-seronegative and HLA-compatible, crossmatch-compatible and/or low anti-A/B.

Pooled platelets can only be CMV-seronegative and/or irradiated.

 

<< Previous page: Red cells  |  Next page: Fresh frozen plasma >>