Effect of Ephedrine on Pain and Hemodynamic Status on Injection of Propofol

Abstract

Background: Propofol is one of the drugs most commonly used during induction of anesthesia. The induction dose of propofol can lead to hemodynamic changes such as hypotension and bradycardia. Pain on injection is another side effect of propofol. The purpose of this study was to evaluate the effect of two different doses of ephedrine on hemodynamic status and pain on injection of propofol compared to lidocaine and placebo.
Methods: In the present study, 100 patients were enrolled. A 22 gauge cannula was inserted into the veins on the non-dominant hand of all patients. The patients were randomly allocated to 4 groups and 10 ml/kg of saline was administered over 10 minutes from each of the cannulas. Then, patients received either of these pretreatments: 2 ml of Saline (group S); 2 ml lidocaine 2% (40 mg) (group L); Ephedrine (30 ug/kg) (group E1); or Ephedrine (70 ug/kg) (group E2). After 30 seconds all patients were administered 2.5 mg/kg of propofol with a rate of 1 ml per second. The patients were asked to give a score from 0 to 10 (0 = no pain and 10 = most severe pain) every 5 seconds until loss of consciousness. Systolic and diastolic pressures and heart rate were recorded before induction of anesthesia, before intubation, and 1, 3, and 5 minutes after intubation.
Results: Systolic, diastolic, and mean arterial pressure and heart rate following induction in E1 and E2 groups were higher than S and L groups (P < 0.001). There were no differences in systolic, diastolic, and mean arterial pressure and heart rate 1, 3, and 5 minutes after intubation between groups. Lidocaine and both doses of ephedrine reduced pain on injection of propofol similarly.
Conclusions: Lidocaine and high and low doses of ephedrine reduce the intensity of pain on injection of propofol. Small doses of ephedrine attenuate blood pressure and heart rate reduction after induction of anesthesia with propofol.