Supplementary Material for: Platelet additive solutions SSP+ and T-PAS+ are interchangeable for platelet concentrate storage despite differences in composition and plasticizer

Introduction: Platelet additive solutions support ex vivo storage of platelet concentrates used for transfusion. The composition of platelet additive solutions within one generation (i.e. PAS-E) is similar but not identical. Additionally, the platelet additive solution storage bag may contain different plasticizers. This study compares the effect of two PAS-E solutions (SSP+ vs. T-PAS+, stored in a DEHP-containing and DEHP-free bag, respectively) to investigate if both additive solutions are interchangeable for platelet concentrate storage.
Methods: Platelet concentrates stored in plasma supplemented with SSP+ or T-PAS+ were compared by using a pool-and-split design. Platelet metabolism was investigated using a blood gas analyzer. The degree of platelet storage lesion was determined by flow cytometry to measure granule release and phosphatidylserine scrambling.
Results: The quality of platelet concentrates stored in either SSP+ or T-PAS+ is acceptable as pH decreased only slightly as a function of time. PH remained above 7.2 one day post expiration (day 6), which is far above the minimal criterium of 6.4. Platelet storage lesion was comparable between the two study groups with only limited α-granule release and phosphatidylserine surface expression in both groups after storage for five days, P = 0.547 and P = 0.825 respectively.
Conclusion: This study supports a safe switch between SSP+ and T-PAS+ storage solutions for platelet concentrates despite slight differences in storage solution composition and DEHP content.