Maintenance of vitamin and trace element status in intravenous nutrition using a complete nutritive mixture

Complete nutritive mixtures (CNM) of all intravenous nutrients including fat emulsions are being used increasingly because of their convenience. However, this may lead to chemical interactions and reduce the amount of active vitamins and trace elements made available to the patient. We have studied the effects on micronutrient status of provision of all nutrients in one 3-liter bag (CNM: amino acids, dextrose, Intralipid 20%, a nine-element trace metal mixture, and complete fat- and water-soluble vitamin mixtures) in 10 postoperative surgical patients [median intravenous nutrition (IVN) 14.5 days, range 7-38]. A similar group received the fat emulsion plus water- and fat-soluble vitamins as a separate infusion (SI) from a 3-liter bag (median IVN 14.0 days, range 8-28). Serum and urine magnesium, zinc, copper, manganese, chromium, and selenium, serum vitamins A, E, C, folate, and B12, RBC B1, B2 B6, and folate and leukocyte vitamin C were measured at weekly intervals. All patients in both groups maintained or improved their status for all the micronutrients analyzed. No significant differences between the CNM and SI groups were found in blood concentrations of any of the elements or vitamins. Only for urine copper did the CNM lead to increased excretion (1.51 +/- 0.59 mumol/24 hr; copper input 20 mumol/day), compared to SI (1.00 +/- 0.70 mumol/day, p less than 0.001 Mann-Whitney test) suggesting possible interaction. It is concluded that micronutrient status was maintained during short-term IVN with the CNM and that it did not lead to a significantly greater loss of vitamins or essential trace elements than the SI system.