Stability Of Parenteral Nutrition Admixtures Research Articles

Safety in parenteral nutrition compounding.

Parenteral nutrition (PN) compounding is a complex process that requires knowledge and training to ensure the safety and efficacy of this form of nutrition support therapy. Unfortunately, errors and lack of adherence to safe PN compounding recommendations and sterile compounding requirements have resulted in patient injury and death. These lapses in the safe provision of PN have been the result of various factors, including a lack of understanding of PN compatibility, stability, and sterility requirements, as well as drug product shortages and order entry errors. This review will describe the current challenges with the education and training regarding PN compounding, compatibility and stability of PN admixtures, simultaneous administration of nonnutrient medications with PN admixtures, and specific challenges with special populations such as neonates, pediatrics, and those receiving home care.

Basics in clinical nutrition: Stability of parenteral nutrition admixtures

AIO admixtures are parenteral nutrition formulations containing water, glucose, 15–20 amino acids, lipids, 10–12 electrolytes, 9 trace elements and 11–12 vitamins in a single container. For practical reasons some medications (e.g. insulin, cimetidine and ranitidine) may be added to the admixture in order to maintain acting concentration in serum, decreasing total volume of fluids infused, reducing the risk of contamination and the cost of equipment. All these ingredients and additives and order in which they are added and ways of delivery influence the overall TPN admixture stability. Stability means that the admixture maintains the same status throughout the defined period of time (storage and delivery). Features of stability are:

Analysis of all-in-one parenteral nutrition admixtures by liquid chromatography and laser diffraction: study of stability.

All-in-one parenteral nutrition admixtures are complex lipid emulsions (oil/water) which require absolute sterility, stability and no precipitates. Particle diameter must be in the range 0.4--1 microm in order to mime the size of chylomicra. Added vitamins must not degrade during infusion time (24 h). In this study, the physicochemical stability of parenteral nutrition admixtures was tested in the course of time at different storage temperatures. Two liquid chromatographic methods, based on solid phase extraction (SPE), were developed for fat-soluble vitamin determination. Stability studies were carried out on three industrial lipid emulsions and on six compounded all-in-one admixtures. They were stored at three different temperatures: 4 degrees C (storage), 25 degrees C (compounding) and 37 degrees C (infusion); then they were analyzed at starting time and at 24, 48 and 72 h after compounding. Particle diameter was determined by means of Laser Particle Sizer Analysette 22, which uses laser diffraction technique (light scattering -- reverse Fourier optics). Fat-soluble vitamins (retinol palmitate and alpha-, delta-, gamma-tocopherol) were determined in admixtures with a branded vitamin compound called Idroplurivit Liofilizzato. Samples were extracted by SPE on C(18) cartridges, then they were separated by reversed-phase liquid chromatography (LC) and detected by ultraviolet detection (retinol palmitate) and electrochemical detection (tocopherols). Laser diffraction analysis pointed out that particle size did not change in the course of time at the tested temperatures. LC analysis showed that vitamins interact each other and degrade after compounding at different times and storage temperatures; only retinol palmitate is stable at 37 degrees C. Retinol palmitate recovery was 98%, coefficient of variation (CV) 5.4%, detection limit 25 microg/l, limit of quantitation 75 microg/l and there were not interfering substances. Tocopherols average recovery was 99%, CV 3.5%, detection limit 15 ng/l and limit of quantitation 50 ng/l. In conclusion, all-in-one parenteral admixtures were proved to be physically stable under analysis conditions, but degradation of retinol palmitate and tocopherols requires admixtures with vitamins to be infused within 24 h after compounding.

Stability of parenteral nutrition admixtures containing organic phosphates

The use of organic phosphates to avoid calcium phosphate precipitation in parenteral nutrition mixtures has been proposed. The purpose of this study was to evaluate the stability of total parenteral nutrition admixtures containing glucose-1-phosphate or glycerol phosphate as the phosphate source over 3 days. Three parenteral nutrition admixtures, each containing glucose-1-phosphate (30.0 mmol), glycerol phosphate (31.4 mmol) or inorganic phosphate (30.0 mmol), and their corresponding aqueous phases were prepared in 3-L ethylene vinyl acetate plastic bags and infusion bottles, and stored at 5 ± 1°C or 22 ± 3°C without light protection. Physical stability analysis and sampling for chemical analysis was performed at 0, 24, 48 and 72 h. Aqueous phases were subjected to physical stability analysis, including pH measurement, visual inspection and nephelometry. Admixtures were subjected to physical stability analysis consisting of pH measurement, and evaluation of emulsion stability by visual inspection, degree of creaming, phase contrast microscopy, zone sensing technique and photon correlation spectroscopy. Chemical analyses of amino-acids, dextrose, triglycerides, phospholipids, Na, K, Cl, Mg, Ca, glucose-1-phosphate, glycerolphosphate and inorganic phosphate were performed. No precipitation was detected in any of the aqueous phases. Admixtures remained acceptable with respect to visual and microscopic appearance, mean droplet diameter and droplet size distribution. All nutrient concentrations assayed in the three admixtures remained constant over the study period. Total parenteral nutrition admixtures for adult patients containing glucose-1-phosphate or glycerolphosphate are physically and chemically stable for 3 days when stored under refrigeration or controlled room temperature without light protection.