Final answer:
Once opened, a vial of propofol should be used within 6 hours to minimize the risk of bacterial contamination and infection.
Step-by-step explanation:
The question asked pertains to the stability and use of propofol after it has been opened. Propofol is an intravenous sedative-hypnotic agent used for the induction and maintenance of anesthesia or sedation. Once a vial of propofol is opened, it should be used within 6 hours because of the risk of bacterial contamination. After this period, the remaining propofol should be discarded. Propofol formulations do not contain preservatives and thus are prone to the growth of microorganisms. The 6-hour rule is a safety guideline to minimize the risk of infection to patients.