In 6 blood units with increased duration of storage alterations of amino acid levels were measured. Total amino acid concentration rises to 27%, while the amount of essential amino acids increases to 11% The E/T-quotient decreases slightly; so does the quotient of essential to non essential amino acids. The changes of concentrations of amino acids in stored whole blood can deteriorate the metabolic situation of patients with disorders of liver or kidney function. These patients as well as intensive care patients, in whom insufficiency of liver and kidney often is seen, should get transfusions of packed cells instead of whole blood.
