Efficacy of the lidocaine/flurbiprofen axetil combination for reducing pain during the injection of propofol.

BACKGROUND: Pain during the injection of propofol is a common clinical problem. Lidocaine pretreatment, preceded by venous occlusion, is the most popular method for reducing pain during the injection of propofol but cannot entirely control such pain. We aimed to evaluate the efficacy of lidocaine, flurbiprofen axetil (an injectable prodrug of flurbiprofen), and the two in combination for reducing pain during the injection of propofol.

METHODS: This prospective, randomized, double-blind, placebo-controlled study was conducted at the Department of Anesthesiology, Ushiku Aiwa General Hospital, Ibaraki, Japan. One hundred patients, 55 men and 45 women aged 22-69 years old and with ASA physical statuses of I-II, were randomly allocated to one of four groups to receive intravenously placebo (saline), lidocaine 40 mg, flurbiprofen axetil 50 mg, or both (N=25 for each group), with venous occlusion for 2 minutes, followed by administration of propofol 0.5 mg/kg into a dorsal hand vein. A blind researcher asked the patients to assess pain during injection of propofol.

RESULTS: The treatment groups were comparable with respect to patient characteristics. The overall incidence of propofol-induced pain was 32% with lidocaine (P=0.001), 40% with flurbiprofen axetil (P = 0.001), and 8% with both (P=0.001), compared with 88% with placebo. The incidence of such pain was lower in patients receiving the lidocaine/flurbiprofen axetil combination than in those receiving lidocaine or flurbiprofen (P=0.036, combination vs. lidocaine; P=0.009, combination vs. flurbiprofen axetil).

CONCLUSION: The lidocaine/flurbiprofen axetil combination, compared with lidocaine 40 mg or flurbiprofen 50 mg, effectively reduces pain during the injection of propofol.