Storage

Proper storage is a dynamic process requiring the right solutions, strict temperature control (both static and during transport), awareness of the inevitable product changes over time, and strict adherence to expiration dates, especially after any manipulation, to ensure patient safety and transfusion efficacy. Think of proper storage as maintaining a carefully controlled environment that preserves the safety and effectiveness of these life-saving components from the moment they are processed until they reach the patient

Storage encompasses the solutions used, the critical temperatures maintained, how products are moved, the changes they undergo, and the ultimate limits on their use (expiration)

Anticoagulants/Additives (The Preservation Formula)

• Purpose: Prevent clotting (using citrate to bind calcium) and maintain cell viability (using dextrose for energy, adenine for ATP synthesis, phosphate as a buffer)
• Impact: The specific formulation dictates RBC shelf life. Early solutions (CPD) allowed 21 days; adding adenine (CPDA-1) extended it to 35 days. Modern Additive Solutions (AS), added to RBCs after plasma removal, contain saline, dextrose, adenine (+/- mannitol) and allow for 42-day storage while providing a lower hematocrit component

Temperature Requirements (The Climate Control)

• Critical: Essential for preventing bacterial growth and maintaining component function
• Specific Ranges
  • RBCs (Liquid): 1°C to 6°C (Slows metabolism, prevents freezing/hemolysis)
  • Platelets: 20°C to 24°C with continuous agitation (Prevents cold activation, allows gas exchange)
  • Plasma / Cryoprecipitate (Frozen): ≤ -18°C (Preserves coagulation factors)
  • Granulocytes: 20°C to 24°C (No agitation, very short storage)
• Monitoring: Requires calibrated thermometers, alarms, and regular checks

Transportation (Storage on the Move)

• Goal: Maintain required temperature range outside of monitored storage units
• Method: Use validated containers and appropriate packing:
  • RBCs (1-10°C transport range): Wet ice or cool packs (avoid direct contact)
  • Platelets (20-24°C): Insulated container, no coolant
  • Frozen Products (Solidly frozen): Dry ice or validated ultra-low temp shippers
• Key: Validation, secure packing, minimizing transit time, and documentation (chain of custody) are crucial

Properties of Stored Products (What Happens Over Time)

• RBC “Storage Lesion”: During 1-6°C storage, RBCs experience decreased ATP & 2,3-DPG (affecting energy/O₂ release), pH drop, potassium (K+) leakage out, shape changes (less deformable), and some hemolysis (free hemoglobin in supernatant)
• Platelets: At 20-24°C, risk of bacterial growth is significant. pH drops due to metabolism; viability/function can decrease over the 5-7 day shelf life
• Plasma/Cryo: Frozen state preserves most factors well, but labile factors (V, VIII) degrade slowly (defining 1 yr expiry) and rapidly upon thawing

Expiration (The Use-By Date)

• Basis: Set by regulators based on loss of viability/function and safety risks (e.g., bacteria)
• Standard Dates: Depend on component and anticoagulant/additive (e.g., AS RBCs = 42 days; Platelets = 5-7 days; FFP/Cryo = 1 year frozen)
• Modifications Shorten Expiry
  • Open Systems: (washing, pooling): Expiry often becomes 4 hours (platelets, pooled cryo) or 24 hours (washed RBCs)
  • Thawing: Plasma expires in 24 hrs (or 5 days as “Thawed Plasma”) at 1-6°C; Cryo expires in 4-6 hrs at room temp
  • Irradiation: RBC expiry becomes original outdate OR 28 days post-irradiation, whichever is sooner