Among children in Uganda with lactic acidosis due to severe anemia, transfusion of longer-storage red blood cells, compared with shorter-storage, resulted in a similar reduction of elevated blood lactate levels, a measure of tissue oxygenation, according to a study published by JAMA. The study is being released to coincide with its presentation at the American Society of Hematology annual meeting.

During storage, red blood cells (RBCs) undergo changes that might impair the capacity for tissue oxygenation by transfused RBCs. Although millions of transfusions are given annually worldwide, the effect of RBC unit storage duration on oxygen delivery is uncertain. Walter H. Dzik, M.D., of Harvard Medical School and Massachusetts General Hospital, Boston, and colleagues randomly assigned 290 children (age 6-60 months) with elevated blood lactate levels due to severe anemia to receive RBC units stored 25 to 35 days (longer-storage group; n = 145) vs 1 to10 days (shorter-storage group; n = 145). The study included children who presented to a university-affiliated national referral hospital in Kampala, Uganda.

The researchers found that RBC units maintained under standard storage conditions for 25 to 35 days were not inferior to RBC units stored for up to 10 days as measured either by resolution of lactic acidosis at 8 hours or by secondary outcomes defined by improvement in clinical symptoms, normalization of vital signs, correction of laboratory abnormalities, and improvement in cerebral tissue (brain) oxygen saturation. Average lactate levels were not statistically different between the 2 groups at 0, 2, 4, 6, 8, or 24 hours, and analysis indicated no statistical difference in lactate reduction between the 2 groups. Adverse events, survival, and 30-day recovery were also not significantly different between the groups.

"This study provides biological evidence that longer-storage RBCs correct lactic acidosis and increase cerebral tissue oxygenation as effectively as shorter-storage RBCs," the authors write.

Editorial: Storage Duration and Other Measures of Quality of Red Blood Cells for Transfusion

"More complete data throughout the continuum from donation to transfusion are needed to improve outcomes for patients requiring transfusions," write Philip C. Spinella, M.D., F.C.C.M., of Washington University in St. Louis, and Jason Acker, M.B.A., Ph.D., of the University of Alberta, Edmonton, Canada, in an accompanying editorial.

"Blood collection centers and hospital blood banks need to collect and share information on donor characteristics and quality metrics from the RBCs donated. Hospitals should collect data on patients receiving transfusions, the indications for transfusion, the timing and dose of each blood product transfused, and the physiologic response to transfusion. Administrative data sets need to be linked to each of these data sets to allow cost-effective analyses to be performed. Only with better data can future studies determine which therapies or strategies are optimal to improve outcomes for patients requiring transfusions."