Topical anesthesia in preterm neonate: a reflection on the underutilization in clinical practice

Premature neonates are customarily submitted to invasive painful procedures during their stay in NICUs that are necessary to maintain their clinically stability. Topical anesthesia is a good option to be considered in the treatment of interventions that lead to mild to moderate pain and has the advantage of no systemic effects. In Brazil the most known topical anesthetic available for use is the eutectic mixture of local anesthetics (EMLA® cream). Its efficacy in the treatment of cutaneous painful procedures is well established for children and adults. Its utilization in neonates has been investigated also due to the risk to develop methemoglobinemia. The procedures in which topical anesthesia would be well indicated are those related to mild to moderate pain like: arterial and venous punction, hell lance puncture, lumbar puncture and percutaneous central catheter installation. The studies in the literature have so far lead to different conclusions, mainly depending on the type of the procedure and also due to the use of very different methodologies. The possibility of a direct pain evaluation may decrease the methodological bias leading to a more accurate evaluation of the efficacy of the topical anesthesia and also allowing comparisons among the indirect pain measures used so far.