A hospital pharmacy policy states that an opened propofol syringe must be discarded after 6 hours even if unused drug remains. The basis for this rule is:

• A Propofol undergoes spontaneous oxidation to toxic quinones at room temperature
• B Disodium edetate in the formulation precipitates after 6 hours
• C The lipid vehicle supports rapid growth of microorganisms such as Candida albicans ✓
• D Free phenol released from degradation causes phlebitis

Explanation

Propofol is formulated as a 1 percent emulsion in soybean oil, glycerol and egg phosphatide, which is an excellent culture medium. Outbreaks of postoperative infection traced to extrinsically contaminated propofol led to the recommendation that drawn-up drug be discarded within 6 hours. Formulations containing disodium edetate or metabisulfite retard bacterial growth, but the discard convention remains standard practice.

Reference: Miller's Anesthesia, 9th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.