Pain on Injection of Lipid-Free Propofol and Propofol Emulsion Containing Medium-Chain Triglyceride: A Comparative Study

Abstract

Pain on injection of propofol continues to be a problem for anesthesiologists. A lipid-free formulation of propofol and a propofol emulsion containing medium-chain triglyceride have become available in the Indian market. We performed this study to assess the pain on injection of propofol emulsion containing medium-chain triglyceride as the lipid carrier and lipid-free propofol formulation. One-hundred-thirty adult patients were randomly assigned to one of two groups: Group I received propofol emulsion containing medium-chain triglyceride and Group II received lipid-free propofol. One fourth of the total calculated induction dose was injected over 5 s in the largest vein on the dorsum of a hand. Pain was assessed using verbal response and behavioral signs. Both formulations caused pain on injection. However, the lipid-free propofol solution produced frequent (89%) and severe pain on injection compared with the emulsion containing medium-chain triglyceride (40%). Pain on injection of two formulations of propofol was compared. A lipid-free formulation produced more pain on injection as compared with the emulsion containing medium-chain triglyceride.