Methemoglobinemia due to prilocaine administration

Prilocaine is the one of the most utilized agents during dorsal penile block in order to prevent pain during circumcision. It is known that prilocaine may lead to methemoglobinemia in neonates and infants. Here we present a 56 days old male patient with prilocaine induced methemoglobinemia who had been referred to intensive care unit for his frank and instant cyanosis after circumcision. Detailed history taking revealed that he needed 1 mg/kg prilocaine administration twice for adequate anesthesia. Patient had frank cyanosis at administration with no other sign. During admission rate of methemoglobin was 16,2% in the blood of the patient and conservative measures lead to complete resolution of all symptoms. Since infants below six months of age are particularly prone to methemoglobinemia due to their low cytochrome b5 levels and fetal hemoglobine is closer to “ferric” state than adult hemoglobine, it is emphasized in this paper that other alternative anesthetic agents should be utilized instead of prilocaine for regional anesthesia in infants under six months age. (Turk Arch Ped 2012; 47: 305-6)