The pH and titratable acidity of stored CPD blood

Blood stored in citrate-phosphate-dextrose (CPD) solution for periods up to 20 days had a mean pH 6.71. The mean metabolic hydrogen ion excess was 32 mmol/litre and the mean respiratory hydrogen ion excess was 80 mmol/litre. These results for CPD blood are compared with those obtained on acid-citrate-dextrose blood. A prediction is made that clnically, only small variations in metabolic and respiratory acid-base balance would be produced directly due to the acid and base loads in transfused blood.