Decrease of available vitamin A in parenteral nutrition solutions.

ABSTRACT

The efficiency of vitamin A delivery in total parenteral nutrition solutions was determined using spectrofluorometric and radioisotope assays. Experiments incubating total parenteral nutrition solutions in intravenous tubing demonstrated that an 88% decrease in vitamin A content from solution occurred over a 5-hr period. This decrease was independent of the method of assay and was not due to photodecomposition. Recovery of vitamin A from hexane rinses of the intravenous tubing demonstrated that the vitamin decrease was due to uptake by the tubing. Experiments simulating clinical practice situations showed saturation of these binding sites, with mean decrease of 26 to 67% of the vitamin, which were partially dependent on flow-rate. Clinical samples analyzed for comparison showed a greater loss of vitamin (77-98%) from the intravenous solutions. A decrease of vitamin A from solution should be a consideration when using parenteral nutrition.