Irradiating stored blood and storing irradiated blood: Is it different? - A study of serial changes in biochemical parameters of red blood cell units

INTRODUCTION: Gamma Irradiation of blood products accentuates biochemical changes in the blood stored at 4°C. This study tried to compare the changes in potassium, sodium, glucose, lactate, and lactate dehydrogenase (LDH) levels in packed red blood cell (PRBC) units irradiated at various time points and then stored versus those stored for a particular period then irradiated. METHODOLOGY: One hundred and eighty units of RBCs were randomly assigned equally to be irradiated or not. Eighteen units each were irradiated by gamma irradiator using cobalt 60 (BI 2000) on day 1, 7, 14, 21, and 28 of their storage, respectively, in the irradiation group. All the units were assessed for their plasma levels of potassium, sodium, glucose, LDH, and lactate by clinical chemistry auto analyzer Beckman coulter AU680 weekly. The values were documented and analyzed by SPSS. RESULTS: Baseline values on day 1 for studied biochemical parameters were comparable between irradiated and nonirradiated groups. Mean values of potassium, lactate and LDH were higher in irradiated than nonirradiated PRBC bags. In contrast, Sodium and Glucose mean values were lower than baseline values. Maximum cumulative mean values were noted in day-21 irradiated bags when the parameters were measured on day-28 for potassium and lactate levels. This was followed by day 14 irradiated bags, followed by day 7 irradiated bags. CONCLUSION: The study indicates that irradiation of red cells later in their storage period had comparatively more detrimental changes in relation to potassium and lactate than irradiation in earlier days. Consideration of irradiation to be performed as close to the issue as possible to reduce a lesser number of days of storage postirradiation is to be explored.