Intraarterial Lidocaine Administration for Pain Control by Water-in-Oil Technique in Transarterial Chemoembolization: in vivo and Randomized Clinical Trial

OBJECTIVE: To investigate the sustained release of lidocaine from a lidocaine–epirubicin–lipiodol emulsion created by water-in-oil (W/O) technique in vivo and evaluate the efficacy and safety of intraarterial lidocaine administration for intra- and postoperative pain control in transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). METHODS: The in vivo concentrations of lidocaine were determined in tumor tissues after VX2 rabbit models for hepatic tumor were administered with intra-arterial lidocaine–epirubicin–lipiodol emulsion. A prospective randomized controlled clinical trial was performed, enrolling 70 consecutive patients who underwent TACE. Patients were randomized into two groups: Group A received an immediate bolus intraarterial lidocaine injection before TACE, and Group B received a lidocaine–epirubicin–lipiodol emulsion during TACE. Pain intensity was compared between the two groups using a visual analog scale (VAS) score before (T(before)) and at 0 h (T(0)), 4 h (T(4)), 8 h (T(8)), 24 h (T(24)), 48 h (T(48)), and 72 h (T(72)) after the procedure. Adverse events and intake of analgesics were evaluated and compared between the two groups. RESULTS: The concentrations of lidocaine in tumor tissues were higher in experimental group than in control group at T(0.5) (P=0.004), T(1) (P=0.038), T(4) (P=0.036), and T(8) (P=0.029). In the clinical trial, VAS scores in Group B were significantly lower than in Group A at T(0) (P=0.006), T(4) (P=0.001), T(8) (P=0.002), and T(24) (P=0.005). The tramadol intake in Group B was significantly lower than in Group A (P=0.021). No significant difference was observed regarding the incidence of adverse events between the two groups. CONCLUSION: This study demonstrated the effectiveness and safety of intraarterial lidocaine administration using the W/O technique in controlling intra- and post-TACE pain.