Optimization of blood supply chains under different supply scenarios

Blood is a living tissue of unique value to the human body and has special features with short shelf life, unpredictable supply, and stochastic demand. The efficiency of blood management affects the quality of medical services. Scholars pay more attention to demand uncertainty than to supply uncertainty in blood supply chain management, which leads to a lack of research on supply uncertainty in such management. We take supply uncertainty into account and discuss three different uncertainty scenarios: optimistic, average, and pessimistic supply scenarios. Different supply scenarios will affect not only the quantity of orders but also the inventory freshness. To balance the fairness of the old inventory allocation, we designed a hybrid allocation policy of old stocks by order share and batch allocation of other stocks by hospital priority. The simulation results reveal the direct and cross effects of supply uncertainty, life cycle, and old inventory ratio (OIR) policy on the system-wide outdating rate. First, for the effect of supply uncertainty, when it is smaller, the system's outdate rate grows with the increase of its intensity, but when it is larger, the outdate rate hardly grows and even decreases in intensity. Especially, when the supply uncertainty is larger, the expected supply scenarios have no significant effect on the outdate rate. Second, for the effect of product shelf life, when the shelf life is longer, the OIR policy can significantly reduce the system's outdate rate in the optimistic or average supply scenarios and has little impact on the rate in the pessimistic supply scenario. Third, for the effect of the OIR policy, when the intensity of supply uncertainty is smaller, the OIR policy leads to a large increase in the system's outdate rate as supply uncertainty grows. However, when the intensity of supply uncertainty is larger, the range of increase in system outdate rate further increases in the optimistic scenario. In contrast, in the pessimistic scenario, it will decrease. Besides, the OIR policy will have no significant effect on the outdate rate when the supply uncertainty is smaller.