METHEMOGLOBIN FORMATION AFTER THE USE OF EMLA CREAM IN TERM NEONATES

EMLA cream 5% (a eutectic mixture of lidocaine and prilocaine) is a to pical anaesthetic that has become widely used to minimize pain from ve nipuncture in children. It has not, however, been recommended in neona tes owing to the potential risk of methaemoglobinaemia induced by pril ocaine. The aim of this study was to establish the safety of 1g EMLA c ream 5% used on intact skin in term neonates. Forty-seven neonates, ag ed 0-3 months, with a postconceptual age of greater than or equal to 3 7 weeks and a body weight between 2.8 and 5.7 kg, were included in a d ouble-blind, randomized, placebo-controlled study. After baseline obse rvations a total dose of 1.0 g EMLA/placebo was applied to two sites ( 0.5 g site(-1)) for 60-70 min. Venous methaemoglobin (metHb) levels we re determined in each patient at baseline and at three randomly assign ed times, 0.5-18 h after application. Following application of the cre am, the mean metHb levels were 1.17% (range 0.50-2.53) in the EMLA gro up and 0.96% (range 0.50-1.53) in the placebo group. The metHb concent rations were significantly higher in the EMLA group in the intervals f rom 3.5 to 13 h after application than in the placebo group, but were well below potentially harmful levels. Based on these results, a 1-h a pplication of 1 g EMLA cream is safe when used on the intact skin of t erm neonates below 3 months of age.