Blood management in regional blood banks is considered more challenging because of the large number of participants in the system. We can distinguish between two types of regional systems: centralised and decentralised. In a centralised inventory management system, the regional blood bank supervises the collection, storage, and assignment blood orders to hospitals. This system is based on a scheduled ordering system, while the decentralised system process daily orders from each hospital blood bank which sets its inventory levels. Studies proofed that centralised systems outperform decentralised ones in the number of perished inventory units and shortages, two important criteria for the performance of a blood bank, as well as reducing the average per unit (Prastacos 1984).