A randomized trial of eutectic mixture of local anesthetics during lumbar puncture in newborns.

OBJECTIVE: To determine the efficacy of a topical anesthetic cream, eutectic mixture of local anesthetics (EMLA), in alleviating pain associated with lumbar puncture in newborns.

DESIGN: Randomized double-blind placebo-controlled trial.

SETTING: Neonatal intensive care unit of a university teaching hospital. Patients Sixty consecutive newborns (gestational age, >or=34 weeks) undergoing diagnostic lumbar puncture. Intervention Topical application of 1 g of EMLA or placebo 60 to 90 minutes before lumbar puncture.

MAIN OUTCOME MEASURES: Heart rate, transcutaneous oxygen saturation level, and total behavioral score recorded on a video camera and graded according to the Neonatal Facial Coding System.

RESULTS: Compared with baseline, all newborns experienced pain as evidenced by increased heart rate, decreased oxygen saturation level, and total behavioral score (all within-groups differences were significant using repeated-measures analysis of variance; P<.001) during the procedure. Compared with placebo, EMLA significantly attenuated the pain response as shown by a lower mean +/- SE heart rate (per minute), particularly at needle insertion (EMLA: 159.3 +/- 2.3; placebo: 175.2 +/- 2.7; P<.001) and needle withdrawal (EMLA: 153.8 +/- 2.6; placebo: 167.3 +/- 2.5; P<.001), and a lower mean +/- SE total behavioral score, again at insertion (EMLA: 4.0 +/- 0.3; placebo: 5.0 +/- 0.0; P =.004) and withdrawal (EMLA: 1.8 +/- 0.3; placebo: 3.9 +/- 0.3; P<.001). There was no statistically significant difference between groups with regard to oxygen saturation level.

CONCLUSIONS: Lumbar puncture in newborns produces pain responses. Eutectic mixture of local anesthetics is an efficacious agent for reducing the pain associated with needle insertion and withdrawal during lumbar puncture in newborns.