Visual compatibility of total parenteral nutrition solution (Synthamin 17 Premix®) with selected drugs during simulated Y-site injection

Objective: To evaluate the visual compatibility of a standard total parenteral nutrition solution (Synthamin 17 Premix®), containing electrolytes and glucose 50%, with 41 commonly used intravenous medications during simulated Y-site injection. Study procedure: Concurrent administration of an IV fluid containing a secondary additive at a Y-site was simulated. A ratio of test drug to Synthamin 17 Premix of 1:1 was used. Each combination was prepared twice with order of mixing reversed. Visual examination of all samples was performed using the unaided eye under normal fluorescent light. The samples were further examined against light and dark backgrounds and with the assistance of a 2.5 dioptre magnifying lens. Inspections were performed immediately after mixing and at intervals of 30 minutes, 1 hour, 4 hours and 24 hours. Samples were examined for haze, precipitation, gas production and colour change. Results: Four drugs were shown to be visually incompatible with Synthamin 17 Premix - midazolam, papaveretum, phenytoin sodium and trace elements solution (containing zinc, copper, manganese and chromium). All incompatibilities were observed at initial mixing. No differences due to order of mixing were observed. Conclusions: Simultaneous or sequential administration of Synthamin 17 Premix with the visually incompatible agents, without adequate flushing between them, should be avoided. Even though the majority of drugs tested in this study were found to be visually compatible with Synthamin 17 Premix care should be taken when applying the results to the clinical setting without further testing for chemical stability