The introduction of WCBS’s division of one apheresis platelet donation into three products over a year ago has successfully met the increasing demand for these products, at a time when recruitment of platelet donors has become challenging. Provided the platelet yield of an apheresis donation is sufficiently high, a single donation can be divided equally into three individual platelet products, thereby helping multiple patients.
At WCBS, adult single donor platelet issues increased by 19% from 2020 to 2024, and pooled platelet issues increased by 10% from 2020 to 2024.
The supply chain management of single donor platelets has improved with the introduction of the three-way split, enabling emergency platelet supplies to be maintained at both Tygerberg and Groote Schuur Blood Banks. Stock management has also been streamlined by utilising apheresis platelets that are nearing expiry as leucocyte-filtered, pooled platelets, ensuring optimal resource utilisation and reducing waste. Clinicians are reminded that unused platelet products may be returned to the Blood Bank within six hours of issue for use by other patients.
Each adult single donor platelet has a minimum platelet count ≥ 2.4 × 1011/L, volume ≥ 200 mL, leucocyte count ≤ 5 × 106/unit, pH > 6.4 at 20–24 °C, and a shelf life of five days. Platelets must be stored under continuous gentle agitation at 20 °C – 24 °C to prevent aggregation.
All WCBS platelets contain platelet additive solution, which is a buffered salt solution that contains acetate as a replacement for glucose, to fuel platelet metabolism, effectively preventing acidification of the storage environment. Other additives, including potassium and magnesium, improve platelet recovery and survival for up to seven days. The use of platelet additive solution rather than plasma as a storage medium for platelets also reduces the risk of allergic and acute haemolytic transfusion reactions in patients.
Platelet transfusions are indicated for the prevention (prophylactic transfusions) and treatment (therapeutic transfusions) of bleeding in patients with thrombocytopenia or platelet function defects. Recommended indications for platelet transfusions are available in The Clinical Guidelines for the Use of Blood and Blood Products in South Africa, Sixth Edition (2023), Chapter Five (‘Platelet Product Transfusion’) and Chapter Seven (‘Leucocyte Depletion and Irradiation of Blood Components’).
Please contact your nearest Blood Bank to order single donor platelets for your patient. It is important to note that the turnaround time for HLA-matched single donor platelets is longer because suitable donors must be identified through the South African Bone Marrow Registry.
For more information about single donor platelet products, contact Dr Thembie Sitsila, Head — Medical Division (Thembie.Sitsila@wcbs.org.za).
