Combination of Magnesium and Lidocaine for the Pretreatment of Pain That is Caused by the Injection of Propofol

Since the introduction of propofol into routine anesthesia practice, the phenomena of pain on injection has plagued anesthesia providers. Propofol, an unstable phenol, triggers the release of bradykinin on injection. This release causes a painful burning sensation in the patient at the site of injection. Anesthesia providers have attempted a large number of remedies to prevent this pain on injection. Previously explored ideas include injecting propofol into larger veins, warming of the hand with hot packs, and intravenous pretreatment with numerous other medications. Currently, pretreatment with lidocaine is commonly administered to prevent propofol injection pain. No studies to date have looked at the combination of lidocaine and magnesium in a single syringe for the pretreatment of pain on injection caused by propofol. In addition, the administration protocols that have been studied thus far do not mirror clinical practice at the University of Wisconsin. The investigators propose studying the use of magnesium and lidocaine in a single syringe for pretreatment of propofol related pain on injection.