Platelets

For apheresis platelets, an apheresis machine separates anticoagulated blood into components and retains platelets and a portion of plasma, which are resuspended in a bag containing platelet additive solution (PAS). The remaining elements (red and white blood cells) and the majority of the plasma are either returned to the donor or collected for preparation of other component types.

One, two or three adult doses of platelets may be prepared from a single apheresis platelet donation. If required, one adult apheresis platelet dose can be divided into three units to produce paediatric apheresis platelets.  This reduces donor exposure for paediatric recipients and minimises product wastage.

Whole blood derived platelets are produced by harvesting platelets from a pool of buffy coats from four ABO and RhD identical whole blood donations.  The platelets are resuspended in platelet additive solution to produce the pooled platelet component.

Both apheresis and pooled platelets are leucodepleted during or soon after collection and are also irradiated before release from Lifeblood.

Platelets can be stored for 7 days after collection at 20 - 24º C with gentle agitation.

Platelets can be irradiated at any stage during their 7-day storage and thereafter can be stored up to their normal shelf life of 7 days after collection. 

 

Typical unit content and specifications

The typical unit content data is derived from Lifeblood process control testing. For each parameter, the mean value (± 1 SD) and specification is shown.

Unless otherwise specified, data is for the period 1 January to 31 December 2022.

 

Platelet apheresis leucocyte depleted in platelet additive solution (PAS)

Volume (mL)207 ± 11 (100–400)
Platelet count (109 /unit)272 ± 33 (> 200 to < 450)
pH7.2 ± 0.1 (-7.4)
Leucocyte count (106 /unit)0.2 ± 0.1 (< 1.0)
Residual plasma content (%)Approximately 40%

 

Platelets paediatric apheresis leucocyte depleted

Volume (mL)55 ± 1 (40-60)
Platelet count (109 /unit)73 ± 9 (> 60)
pH7.1 ± 0.1 (-7.4)
Leucocyte count (106 /unit)(Initial unit prior to splitting < 1.0)
Residual plasma content (%)Approximately 40%

 

Platelets pooled leucocyte depleted*

Volume (mL)273 ± 12 (> 160)
Platelet count (109 /unit)270 ± 38 (> 200)
pH7.0 ± 0.1 (-7.4)
Leucocyte count (106 /unit)0.01 ± 0.02 (< 1.0)
Residual plasma content (%)Approximately 30%

* Due to process change data is based for the period 1 July to December 2022.

Availability

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

 

Modifications

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

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

 

Apheresis platelets suspended in plasma

Lifeblood stopped producing apheresis platelets suspended in plasma in March 2019. A comparison between the old and new products is available can be found here

Change to Pooled Platelet Components

From July 2022, Australian Red Cross Lifeblood will be changing the way we make buffy coat pooled platelets. We will be reducing the volume of platelet additive solution that we use for resuspension after pooling, from 300mL to 250mL.

As a result, overall pooled platelet volume will reduce on average by 90mLs per unit, and in turn, the volume of residual plasma in each component by approximately 27mL per unit.

Importantly, there is no change to component specification associated with this initiative. Platelet content remains at >200 x109 per unit. A comparison of the component specifications and typical unit content for the current and future pooled platelets is shown here.