Topical lidocaine for anesthesia in patients undergoing pulsed dye laser treatment for vascular malformations

Pulsed dye laser treatment of vascular malformations is moderately painful. Twenty-five percent lidocaine in 70% dimethyl sulfoxide-ethanol was used to achieve anesthesia in patients undergoing the procedure. Thirteen of 14 patients had some degree of anesthesia (average of 51%) ranging from 10% to 100%, with 8 of them experiencing good results (> 50% anesthesia). Diminishment of pain was assessed by comparison of laser therapy on lidocaine-treated versus untreated sites within the vascular malformation using verbal and visual analog scales. In vitro permeation demonstrated good absorption of lidocaine, peaking at one hour. Permeation of lidocaine was significantly greater then that observed from acid mantle cream or EMLA. Topical lidocaine at 25% concentration in dimethyl sulfoxide 70% was well tolerated and had no side effects except transient mild erythema.