Stability of red cell antigens during prolonged storage in citrate-phosphate-dextrose and a new preservative solution

Effect of donor blood storage on gel column crossmatch in dogs

BACKGROUND

Compared with fresh blood, stored equine donor blood results in spurious tube crossmatch incompatibilities. Interpretation of blood crossmatch results is considered subjective.

OBJECTIVES

We aimed to determine if the duration of canine donor blood storage impacts compatibility testing using a standard gel column crossmatch and evaluate interobserver variation in the interpretation of crossmatch results.

METHODS

Observational study. Whole blood segments were obtained from 23 canine packed red blood cell (RBC) units for use in crossmatches after storage for 0, 7, 14, 21, 28, and 35 days. Major and minor crossmatches were performed using serum and RBCs, respectively, from two to three healthy "recipient" dogs per unit. All crossmatch results were interpreted by four observers, of whom three were blinded.

RESULTS

All major crossmatches (n = 61) were compatible on day 0 and remained compatible through day 35 of storage. All minor crossmatches (n = 69) were compatible at all time points, except for five donor pairs with 1 to 3+ agglutination. Repeat testing of these five donor pairs confirmed crossmatch incompatibilities on days 0 through 35, with no change in the degree of incompatibility over time. There was substantial agreement among four observers in determining compatibility (κ = 0.94) and scoring incompatibility (κ = 0.76).

CONCLUSIONS

The current practice of performing canine crossmatches with whole blood segments stored for up to 35 days is acceptable, with no spurious changes in compatibility expected over time. The substantial interobserver agreement suggests that the gel column is suitable for performing canine crossmatches in a laboratory setting with multiple personnel.

Prolonged maintenance of 2,3-diphosphoglycerate acid and adenosine triphosphate in red blood cells during storage

BACKGROUND

Current additive solutions (ASs) for red cells (RBCs) do not maintain a constant level of critical metabolites such as adenosine triphosphate (ATP) and 2,3-diphosphoglycerate acid (2,3-DPG) during cold storage. From the literature it is known that the intracellular pH is an important determinant of RBC metabolism. Therefore, a new, alkaline, AS was developed with the aim to allow cold storage of RBCs with stable product characteristics.

STUDY DESIGN AND METHODS

Whole blood-derived RBCs (leukoreduced) were resuspended in experimental medium phosphate-adenine-guanosine-glucose-gluconate-mannitol (PAGGG-M; pH 8.2) with and without washing in the same medium. During cold storage several in vitro variables, such as intracellular pH, 2,3-DPG, ATP, and hemolysis, were analyzed.

RESULTS

During cold storage, RBCs resuspended in PAGGG-M showed a constant ATP level (approx. 6 mumol/g Hb) and a very limited hemolysis (<0.2%). The 2,3-DPG content showed an increase until Day 21 (150% of initial level), followed by a slow decrease, with at Day 35 still 100 percent of the initial level. RBCs washed in PAGGG-M even showed a continuous increase of 2,3-DPG during 35 days, with a maximum level of 200 percent of the initial value. The effect of PAGGG-M appears to be related to long-lasting effects of the initial intracellular pH shortly after production.

CONCLUSION

Resuspension of RBCs in our alkaline medium PAGGG-M resulted in a RBC unit of high quality during storage for up to at least 35 days, with 2,3-DPG levels of higher than 10 mumol per g Hb, hemolysis of less than 0.2 percent, and ATP levels of higher than 5 mumol per g Hb.

Additive solutions for better blood preservation

For several decades the standard blood preservative solution consisted of citrate, dextrose, and, later, phosphate (ACD and CPD). In 1978 a new solution containing adenine (CPDA-1) was introduced to permit extension of red cell shelf life from 21 to 35 days. The success of CPDA-1 and the high percentage of blood units processed into components (estimated 87% in 1983) have stimulated a burst of research and development activity to develop improved red cell preservation systems. Most of these systems have taken the form of "additive solutions" in which the blood is drawn in CPD or CP2D and processed into components. Then the packed red cells are stored by addition of a solution customized for their preservation. This review evaluates these additive solutions in detail. Innovative systems for pH control (buffers and resins) have also been explored. Our review concludes with discussion of the safety aspects of new preservative solutions and the methodological problems of evaluating these solutions.