The analgesic effect of fentanyl, morphine, meperidine, and lidocaine in the peripheral veins: a comparative study

Using venous retention with a tourniquet (70 mm Hg), we performed a randomized, double-blind study to assess the efficacy of I.V. pretreatment with fentanyl, morphine, meperidine, or lidocaine in reducing propofol injection pain. Immediately after venous occlusion with a tourniquet, I.V. fentanyl 150 microg (Group A, n = 35), morphine 4 mg (Group B, n = 35), meperidine 40 mg (Group C, n = 35), 2% lidocaine 3 mL (Group D, n = 35), or normal saline 3 mL (Group E, n = 35; as placebo control) was given to adult patients. The venous retention of the drug was maintained for 1 min, followed by tourniquet release and I.V. administration of propofol 100 mg. Pain assessment was made immediately after the propofol injection. Lidocaine and meperidine significantly reduced propofol injection pain more than placebo (P < 0.05), but there were more side effects in the meperidine group. Fentanyl and morphine reduced the intensity of propofol injection pain (P < 0.05) and had some effect in reducing the incidence of propofol injection pain, but the difference did not reach statistical significance. The order of efficacy was lidocaine approximately meperidine > morphine approximately fentanyl. We postulate that the peripheral analgesic effect of these opioid is due to their local anesthetic activity.

Propofol, a commonly used anesthetic, often causes pain on injection. Given as venous retention pretreatments 1 min before propofol, meperidine and lidocaine were found to significantly reduce the propofol injection pain, whereas fentanyl and morphine only slightly reduced the propofol injection pain.