A Multi-Period Inventory Model for Blood Supply Chain Management in Blood Banks Across the South East Zone

Effective blood supply chain management is a life-critical operational challenge in Nigerian hospitals, where inadequate blood availability at the point of transfusion contributes to preventable maternal and trauma-related mortality. This study develops a multi-period inventory model for blood supply chain management across the blood banking network of five state hospitals in Nigeria's South East geopolitical zone, covering Abia, Anambra, Ebonyi, Enugu, and Imo States. The perishability of blood products, with maximum shelf lives of 42 days for red blood cells and five days for platelets, introduces specific constraints not present in standard inventory models. A multi-period mixed-integer programming model is formulated to minimize total blood procurement, storage, transport, outdating, and shortage costs across the planning horizon, subject to shelf-life, storage capacity, demand, and supply constraints. Regional demand data are derived from hospital transfusion records covering 18 months, and supply parameters are estimated from blood donation drive frequencies. Results indicate that coordinated regional inventory management, including cross-facility blood transfers, reduces total system cost by 29 percent and outdating rates by 44 percent compared to independent facility-level management. The optimal model recommends establishing a regional blood coordination hub in Enugu, which achieves the greatest reduction in shortage events. Recommendations include adopting the regional inventory model and investing in cold-chain transport capacity. Keywords: blood supply chain, inventory model, perishability, South East Nigeria, blood banking