Propofol Compatibility with other Intravenous Drug Products—Two New Methods of Evaluating IV Emulsion Compatibility

Abstract

OBJECTIVE: To determine the physical compatibility of propofol injection with 77 other drug products using two methods not previously reported. DESIGN: Each of 77 drug products were mixed with (1) an equal volume of propofol injection, (2) an equal volume of propofol injection with methylene blue added, and (3) an equal volume of the separated aqueous phase of propofol injection. The mixtures were observed for physical changes, and the turbidity of the aqueousphase mixtures was measured by nephelometry. SETTING: A university-affiliated urban teaching hospital. MAIN OUTCOME MEASURES: Observed physical changes or changes in turbidity. RESULTS: Of the 77 drugs tested, 69 showed immediate evidence of physical change, and the other 8 were found incompatible within 72 hours. CONCLUSIONS: Practitioners should not mix the immediately incompatible products with propofol by administering them in the same intravenous line. Caution should be used in simultaneous administration of the other drugs. The new methods were useful in detecting incompatibilities in emulsions.