2019 Volume 68 Issue 1 Pages 33-39
We evaluated the changes in the serum inorganic phosphorus (IP) level during whole-blood storage and the effects of hemolysis. During the whole-blood storage at room temperature, the IP level is known to increase owing to the hydrolysis of organic phosphorus. In this study, the evaluation of samples obtained from 10 healthy adults revealed a phenomenon whereby the IP level decreased once prior to its increase in all subjects. This decrease may have been caused by adenosine triphosphate (ATP) synthesis due to glycolysis in red blood cells. The decrease in the IP level was significant, and the maximum decrease rate markedly varied (4–22%). Since the decrease in the IP level during the whole-blood storage at room temperature has not been reported, its details were evaluated using washed red blood cells. As a result, a decrease in the IP level started after about 1 hour, and an increase due to the hydrolysis of organic phosphorus started after about 2 hours. Changes in the IP level are associated with whole-blood storage temperature and glucose concentration. Since changes in the IP level occur early during the whole-blood storage, immediate serum separation after blood collection is necessary. Subsequently, the effects of hemolysis were evaluated using 3 reagents with different measurement principles. The effects immediately after adding the hemolysis solution to the pooled serum slightly differed among the 3 reagents, but the IP level gradually increased during storage at room temperature in the 3 reagents. This increase may have been caused by the hydrolysis of organic phosphorus; thus, the measurement of the IP level in hemolytic serum should be immediately performed.
