Stability of heparin in intravenous fluids

Stability of heparin anticoagulant activity over time in parenteral nutrition solutions

BACKGROUND

Heparin added to parenteral nutrition solutions may decrease the incidence of central venous thrombosis in patients receiving home parenteral nutrition. However, there are little data regarding the stability of heparin over time under conditions similar to those associated with home parenteral nutrition: low concentrations of heparin stored in solutions containing amino acids and high concentrations of dextrose for more than 24 hours.

METHODS

The activity of porcine mucosal heparin was measured over time using an antifactor Xa assay in six IV solutions: four parenteral nutrition solutions containing 25% dextrose; 5% amino acids; trace elements; electrolytes; and 3000, 5000, 10,000, or 20,000 units/L of heparin; one solution of 25% dextrose and 5000 units/L heparin; and one solution of 0.9% saline and 5000 units/L heparin.

RESULTS

In all solutions except 25% dextrose (without amino acids and additives), heparin activity remained stable within 4% of baseline up to 28 days. In the 25% dextrose solution, heparin activity declined by 3%, 6%, and 11% at 14, 21, and 28 days, respectively.

CONCLUSION

Heparin activity was stable over time in the normal saline and parenteral nutrition solutions and decreased slightly from 2 to 4 weeks in the dextrose-containing solution. Based on these data, when home parenteral nutrition is administered containing components similar to the solutions used in this study, heparin may be added at the time of preparation of the home parenteral nutrition solution rather than just before administration, with no resultant loss of heparin activity over time [corrected].