Effect of low dose ephedrine and lidocaine on pain and hemodynamic changes due to propofol injection

ABSTRACT

The aim of this study was to compare the intensity of pain and hemodynamic changes during propofol injection when pretreatment is performed with ephedrine and lidocaine. In a randomized double blind clinical trial [IRCT 2766] in Shahid Rajaee Hospital during the year 2009, 99 patients with ASA physical status I and II, aged 20 to 50 years were recruited. The patients were planned to undergo elective surgeries under general anesthesia and had no history of cardiocascular, neurologic, or allergic diseases. The subjects were randomly assigned into three groups to receive 40mg intravenous lidocaine [group L], 30|jg/kg ephedrine [group E] or 2ml normal saline [group P]. After one minute, 2mg/kg propofol was injected into a dorsal hand vein. Pain was assessed using face pain scale [FPS]. Arterial blood pressure and heart rate were also recorded before induction, just before intubation, and one minute after intubation. Hemodynamic changes and also the incidence and intensity of pain in group L were less than the other groups. The patients in group L had significantly lower FPS compared with group P [P=0.004] and patients in group E had lower FPS compared with group P; however, the difference was not statistically significant [P=0.247]. Pretreatment with a small dose of ephedrine [30 micro g/kg] reduces the incidence and intensity of propofol induced pain. Although lidocaine is more effective, ephedrine results in a more stable hemodynamic status