Parenteral administration of trace elements to critically ill patients.

Studies of zinc, copper, manganese, chromium, selenium and molybdenum balance were carried out in eight patients in an intensive care unit. In six of these, nickel balance was also measured. The amount of each element in fluid administered to the patients, and the amount lost in urine and gastrointestinal fluid on each of seven days, was measured by atomic absorption spectrometry and cumulative balances calculated. Satisfactory balances of zinc, copper and manganese were obtained when the amounts administered approximated those currently recommended. Chromium balances were variable, while those of molybdenum, selenium and nickel were negative in most patients. Interpretation of balance studies of this type in critically ill patients is made difficult by abnormal renal and gastrointestinal function.