French to English Medical Medical (general) blood products

From a series of complaint letters re the French Blood Establishment blood products & batches:

Context:

"L’anomalie signalée est «Trou dans l'une des poches de recueil final du MCP DS entraînant une fuite pendant la phase de décadage» "

MCP is Mélanges de Concentrés Plaquettaires, translated as WBDP - Whole Blood Derived Platelets - but I can't find out anywhere what the DS stands for here.

Thanks in advance!