Warm steaming enhances the topical anesthetic effect of lidocaine.

Unlabelled: Warm steaming has been used for hydrating the skin, thereby increasing its permeability. We studied whether skin pretreatment with a steamed towel (at 45 degrees C) for 5 min could enhance the anesthetic effect of a topical lidocaine tape in 14 female volunteers. After each volunteer received the skin pretreatment on one of the forearms, lidocaine tape was applied for 30 min on both the treated and the untreated forearms. Superficial anesthesia was scored by recording the number of painful experience during 5 pinpricks delivered with a 27-gauge needle. To assess anesthesia of the deeper layer, single insertion of a 27-gauge needle to a depth of 3 mm was made and pain was scored by a visual analog scale (VAS). There were significant reductions in the scores of superficial anesthesia (median [range]: treated arm, 2 [0-5], versus untreated arm, 4 [1-5]; P < 0.01) and the VAS scores of deeper insertion (median [range]: treated arm, 4.5 [0-8], versus untreated arm, 8 [2-10]; P < 0.01). In conclusion, the application of a warm steamed towel enhanced the anesthetic effect of a topical lidocaine tape.

Implications: We showed that the skin pretreatment with a steamed towel (at 45 degrees C) enhanced the anesthetic effect of a topical lidocaine tape in female volunteers.