Compatibility of propofol injectable emulsion with selected drugs during simulated Y-site administration

The compatibility of a new formulation of injectable propofol with selected other drugs during simulated Y-site injection was studied. Two milliliters of undiluted propofol injectable emulsion was combined with 2 mL of each of 112 other drugs in 5% dextrose injection or 0.9% sodium chloride injection. The liquids were diluted with 6 mL of particle-free high-performance liquid chromatography (HPLC)-grade water and centrifuged for 20 minutes. A pipette connected to a vacuum line was used to remove the fat layer at the top and most of the aqueous phase. The remaining liquid was diluted with 9 mt of particle-free HPLC-grade water to facilitate visualization of any precipitate. The liquids were examined with the unaided eye in fluorescent light and with a Tyndall beam to enhance visualization of small particles. Samples were evaluated during the first 15 minutes and one hour after mixing. Propofol injectable emulsion was compatible with 98 of the 112 drugs tested. Fourteen drugs demonstrated incompatibilities, including precipitation, gel formation, and oiling out of cracked emulsions. During simulated Y-site injection, propofol injectable emulsion was compatible with most other drugs tested for one hour at similar to 23 degrees C.