Two red blood cell units collected in SAG-M additive solution with the ALYX component collection system

In vitro quality of red blood cells (RBCs) collected by multicomponent apheresis compared to manually collected RBCs during 49 days of storage

BACKGROUND

New technologic developments enable automated collection and preparation of red blood cells (RBCs). This study's aim was to evaluate quality of apheresis-derived RBCs (ARBCs) collected as single units along with platelets (RBC-Ps) or double units (2-RBCs) with four different apheresis systems.

STUDY DESIGN AND METHODS

Sixty-six donors with similar baseline variables underwent RBC apheresis collection with various machines (Amicus [15 RBC-Ps] and Alyx [15 2-RBCs], Baxter; the Trima Accel [9 RBC-Ps, 8 2-RBCs], Gambro, and the MCS+[9 RBC-Ps, 10 2-RBCs], Haemonetics Corp.). In vitro properties were analyzed during 49 days of storage and compared to manual RBCs (MRBCs, n = 14).

RESULTS

All units but one, Alyx, demonstrated white blood cell counts of less than 1 x 10(6). ARBCs showed lower variability in volume compared to MRBCs. All units met international requirements (European, AABB) for hematocrit (50%-70%), hemoglobin (>40 g/unit), and RBC mass (>or=153 mL). pH values remained similar between study groups without reaching critical limits in any unit. MRBCs had slight advantages for hemolysis at the end of storage and were significantly superior in energy maintenance as indicated by less ATP degradation and potassium leak most likely due to more pronounced anoxidative glycolysis particularly during the first half of storage. Owing to more declining oxidative glucose metabolism, ARBCs demonstrated higher methemoglobin formation and subsequent oxygen release until the end of storage.

CONCLUSION

ARBCs exhibited better predictability in volume and absolute RBC mass than MRBCs and demonstrated sufficient in vitro quality throughout storage, even though lower ATP preservation and higher methemoglobin formation were observed compared to MRBCs probably due to differences in glucose metabolism.

Prospective evaluation of double RBC collection using three different apheresis systems

BACKGROUND

Automated component collection systems offer the possibility of increasing blood supply and improving transfusion safety.

DESIGN

30 blood donors were randomly assigned to double RBC collection with either the Baxter Alyx (AX), the Haemonetics MCS Plus (MCS+), or the Gambro Trima Accel (TA). Procedures were prospectively evaluated focussing on yield, time, efficiency, citrate donor load, and in vitro quality.

RESULTS

All units showed sufficient in vitro quality throughout 42 days of storage and complied with international requirements. Donor reactions were limited to mild citrate reactions. AX was the fastest and most efficient system* * (* *p approximately 0.001) attaining the highest yield* * from similar amounts of whole blood. The drawbacks were a higher RBC loss* (*p < 0.05) and accelerated citrate infusion* *. Due to lower collection rates* * * (* * *p < 0.001), MCS+ was slower than TA* * * but compensated with lower citrate load * * *.

CONCLUSION

Double RBC apheresis was performed safely and efficiently with all three instruments. AX had advantages for most parameters evaluated.